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diff --git a/zh_TW.UTF-8/books/handbook/serialcomms/Makefile b/zh_TW.UTF-8/books/handbook/serialcomms/Makefile deleted file mode 100644 index 3dbd97ce6d..0000000000 --- a/zh_TW.UTF-8/books/handbook/serialcomms/Makefile +++ /dev/null @@ -1,15 +0,0 @@ -# -# Build the Handbook with just the content from this chapter. -# -# $FreeBSD$ -# - -CHAPTERS= serialcomms/chapter.xml - -VPATH= .. - -MASTERDOC= ${.CURDIR}/../${DOC}.${DOCBOOKSUFFIX} - -DOC_PREFIX?= ${.CURDIR}/../../../.. - -.include "../Makefile" diff --git a/zh_TW.UTF-8/books/handbook/serialcomms/chapter.xml b/zh_TW.UTF-8/books/handbook/serialcomms/chapter.xml deleted file mode 100644 index 7c5e70293e..0000000000 --- a/zh_TW.UTF-8/books/handbook/serialcomms/chapter.xml +++ /dev/null @@ -1,2856 +0,0 @@ -<?xml version="1.0" encoding="utf-8"?> -<!-- - The FreeBSD Documentation Project - - $FreeBSD$ - Original revision: 1.108 ---> -<chapter xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" version="5.0" xml:id="serialcomms"> - <title>Serial Communications</title> - - <sect1 xml:id="serial-synopsis"> - <title>Synopsis</title> - - <indexterm><primary>serial communications</primary></indexterm> - <para>&unix; has always had support for serial communications. In fact, - the very first &unix; machines relied on serial lines for user input - and output. Things have changed a lot from the days when the average - <quote>terminal</quote> consisted of a 10-character-per-second serial - printer and a keyboard. This chapter will cover some of the ways in - which FreeBSD uses serial communications.</para> - - <para>After reading this chapter, you will know:</para> - <itemizedlist> - <listitem><para>How to connect terminals to your FreeBSD - system.</para></listitem> - <listitem><para>How to use a modem to dial out to remote - hosts.</para></listitem> - <listitem><para>How to allow remote users to login to your - system with a modem.</para></listitem> - <listitem><para>How to boot your system from a serial - console.</para></listitem> - </itemizedlist> - - <para>Before reading this chapter, you should:</para> - <itemizedlist> - <listitem><para>Know how to configure and install a new kernel (<xref linkend="kernelconfig"/>).</para></listitem> - <listitem><para>Understand &unix; permissions and processes (<xref linkend="basics"/>).</para></listitem> - <listitem><para>Have access to the technical manual for the - serial hardware (modem or multi-port card) that you would like - to use with FreeBSD.</para></listitem> - </itemizedlist> - </sect1> - - <sect1 xml:id="serial"> - <title>Introduction</title> - - <!-- XXX Write me! --> - - <sect2 xml:id="serial-terminology"> - <title>Terminology</title> - - <variablelist> - <indexterm><primary>bits-per-second</primary></indexterm> - <varlistentry> - <term>bps</term> - <listitem> - <para>Bits per Second — the rate at which data is - transmitted</para> - </listitem> - </varlistentry> - - <varlistentry> - <term>DTE</term> - <listitem> - <indexterm><primary>DTE</primary></indexterm> - - <para>Data Terminal Equipment — for example, your - computer</para> - </listitem> - </varlistentry> - - <varlistentry> - <term>DCE</term> - <listitem> - <indexterm><primary>DCE</primary></indexterm> - - <para>Data Communications Equipment — your modem</para> - </listitem> - </varlistentry> - - <varlistentry> - <term>RS-232</term> - <listitem> - <indexterm><primary>RS-232C cables</primary></indexterm> - - <para>EIA standard for hardware serial communications</para> - </listitem> - </varlistentry> - </variablelist> - - <para>When talking about communications data rates, this section - does not use the term <quote>baud</quote>. Baud refers to the - number of electrical state transitions that may be made in a - period of time, while <quote>bps</quote> (bits per second) is - the <emphasis>correct</emphasis> term to use (at least it does not - seem to bother the curmudgeons quite as much).</para> - </sect2> - - <sect2 xml:id="serial-cables-ports"> - <title>Cables and Ports</title> - - <para>To connect a modem or terminal to your FreeBSD system, you - will need a serial port on your computer and the proper cable to connect - to your serial device. If you are already familiar with your - hardware and the cable it requires, you can safely skip this - section.</para> - - <sect3 xml:id="term-cables"> - <title>Cables</title> - - <para>There are several different kinds of serial cables. The - two most common types for our purposes are null-modem cables - and standard (<quote>straight</quote>) RS-232 cables. The documentation - for your hardware should describe the type of cable - required.</para> - - <sect4 xml:id="term-cables-null"> - <title>Null-modem Cables</title> - - <indexterm> - <primary>null-modem cable</primary> - </indexterm> - <para>A null-modem cable passes some signals, such as <quote>Signal - Ground</quote>, straight through, but switches other signals. For - example, the <quote>Transmitted Data</quote> pin on one end goes to the - <quote>Received Data</quote> pin on the other end.</para> - - <para>You can also construct your own null-modem cable for use with - terminals (e.g., for quality purposes). This table shows the RS-232C - <link linkend="serialcomms-signal-names">signals</link> and the pin - numbers on a DB-25 connector. Note that the standard also calls for a - straight-through pin 1 to pin 1 <emphasis>Protective Ground</emphasis> - line, but it is often omitted. Some terminals work OK using only - pins 2, 3 and 7, while others require different configurations than - the examples shown below.</para> - - <table frame="none" pgwide="1"> - <title>DB-25 to DB-25 Null-Modem Cable</title> - - <tgroup cols="5"> - <thead> - <row> - <entry align="left">Signal</entry> - <entry align="left">Pin #</entry> - <entry/> - <entry align="left">Pin #</entry> - <entry align="left">Signal</entry> - </row> - </thead> - - <tbody> - <row> - <entry>SG</entry> - <entry>7</entry> - <entry>connects to</entry> - <entry>7</entry> - <entry>SG</entry> - </row> - - <row> - <entry>TD</entry> - <entry>2</entry> - <entry>connects to</entry> - <entry>3</entry> - <entry>RD</entry> - </row> - - <row> - <entry>RD</entry> - <entry>3</entry> - <entry>connects to</entry> - <entry>2</entry> - <entry>TD</entry> - </row> - - <row> - <entry>RTS</entry> - <entry>4</entry> - <entry>connects to</entry> - <entry>5</entry> - <entry>CTS</entry> - </row> - - <row> - <entry>CTS</entry> - <entry>5</entry> - <entry>connects to</entry> - <entry>4</entry> - <entry>RTS</entry> - </row> - - <row> - <entry>DTR</entry> - <entry>20</entry> - <entry>connects to</entry> - <entry>6</entry> - <entry>DSR</entry> - </row> - - <row> - <entry>DTR</entry> - <entry>20</entry> - <entry>connects to</entry> - <entry>8</entry> - <entry>DCD</entry> - </row> - - <row> - <entry>DSR</entry> - <entry>6</entry> - <entry>connects to</entry> - <entry>20</entry> - <entry>DTR</entry> - </row> - - <row> - <entry>DCD</entry> - <entry>8</entry> - <entry>connects to</entry> - <entry>20</entry> - <entry>DTR</entry> - </row> - </tbody> - </tgroup> - </table> - - <para>Here are two other schemes more common nowadays.</para> - - <table frame="none" pgwide="1"> - <title>DB-9 to DB-9 Null-Modem Cable</title> - - <tgroup cols="5"> - <thead> - <row> - <entry align="left">Signal</entry> - <entry align="left">Pin #</entry> - <entry/> - <entry align="left">Pin #</entry> - <entry align="left">Signal</entry> - </row> - </thead> - - <tbody> - <row> - <entry>RD</entry> - <entry>2</entry> - <entry>connects to</entry> - <entry>3</entry> - <entry>TD</entry> - </row> - - <row> - <entry>TD</entry> - <entry>3</entry> - <entry>connects to</entry> - <entry>2</entry> - <entry>RD</entry> - </row> - - <row> - <entry>DTR</entry> - <entry>4</entry> - <entry>connects to</entry> - <entry>6</entry> - <entry>DSR</entry> - </row> - - <row> - <entry>DTR</entry> - <entry>4</entry> - <entry>connects to</entry> - <entry>1</entry> - <entry>DCD</entry> - </row> - - <row> - <entry>SG</entry> - <entry>5</entry> - <entry>connects to</entry> - <entry>5</entry> - <entry>SG</entry> - </row> - - <row> - <entry>DSR</entry> - <entry>6</entry> - <entry>connects to</entry> - <entry>4</entry> - <entry>DTR</entry> - </row> - - <row> - <entry>DCD</entry> - <entry>1</entry> - <entry>connects to</entry> - <entry>4</entry> - <entry>DTR</entry> - </row> - - <row> - <entry>RTS</entry> - <entry>7</entry> - <entry>connects to</entry> - <entry>8</entry> - <entry>CTS</entry> - </row> - - <row> - <entry>CTS</entry> - <entry>8</entry> - <entry>connects to</entry> - <entry>7</entry> - <entry>RTS</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1"> - <title>DB-9 to DB-25 Null-Modem Cable</title> - - <tgroup cols="5"> - <thead> - <row> - <entry align="left">Signal</entry> - <entry align="left">Pin #</entry> - <entry/> - <entry align="left">Pin #</entry> - <entry align="left">Signal</entry> - </row> - </thead> - - <tbody> - <row> - <entry>RD</entry> - <entry>2</entry> - <entry>connects to</entry> - <entry>2</entry> - <entry>TD</entry> - </row> - - <row> - <entry>TD</entry> - <entry>3</entry> - <entry>connects to</entry> - <entry>3</entry> - <entry>RD</entry> - </row> - - <row> - <entry>DTR</entry> - <entry>4</entry> - <entry>connects to</entry> - <entry>6</entry> - <entry>DSR</entry> - </row> - - <row> - <entry>DTR</entry> - <entry>4</entry> - <entry>connects to</entry> - <entry>8</entry> - <entry>DCD</entry> - </row> - - <row> - <entry>SG</entry> - <entry>5</entry> - <entry>connects to</entry> - <entry>7</entry> - <entry>SG</entry> - </row> - - <row> - <entry>DSR</entry> - <entry>6</entry> - <entry>connects to</entry> - <entry>20</entry> - <entry>DTR</entry> - </row> - - <row> - <entry>DCD</entry> - <entry>1</entry> - <entry>connects to</entry> - <entry>20</entry> - <entry>DTR</entry> - </row> - - <row> - <entry>RTS</entry> - <entry>7</entry> - <entry>connects to</entry> - <entry>5</entry> - <entry>CTS</entry> - </row> - - <row> - <entry>CTS</entry> - <entry>8</entry> - <entry>connects to</entry> - <entry>4</entry> - <entry>RTS</entry> - </row> - </tbody> - </tgroup> - </table> - - <note> - <para>When one pin at one end connects to a pair of pins - at the other end, it is usually implemented with one short - wire between the pair of pins in their connector and a - long wire to the other single pin.</para> - </note> - - <para>The above designs seems to be the most popular. In another - variation (explained in the book <emphasis>RS-232 Made - Easy</emphasis>) SG connects to SG, TD connects to RD, RTS and - CTS connect to DCD, DTR connects to DSR, and vice-versa.</para> - </sect4> - - <sect4 xml:id="term-cables-std"> - <title>Standard RS-232C Cables</title> - <indexterm><primary>RS-232C cables</primary></indexterm> - - <para>A standard serial cable passes all of the RS-232C signals - straight through. That is, the <quote>Transmitted Data</quote> pin on one - end of the cable goes to the <quote>Transmitted Data</quote> pin on the - other end. This is the type of cable to use to connect a modem to your - FreeBSD system, and is also appropriate for some - terminals.</para> - </sect4> - </sect3> - - <sect3 xml:id="term-ports"> - <title>Ports</title> - - <para>Serial ports are the devices through which data is transferred - between the FreeBSD host computer and the terminal. This section - describes the kinds of ports that exist and how they are addressed - in FreeBSD.</para> - - <sect4 xml:id="term-portkinds"> - <title>Kinds of Ports</title> - - <para>Several kinds of serial ports exist. Before you purchase or - construct a cable, you need to make sure it will fit the ports on - your terminal and on the FreeBSD system.</para> - - <para>Most terminals will have DB-25 ports. Personal computers, - including PCs running FreeBSD, will have DB-25 or DB-9 ports. If you - have a multiport serial card for your PC, you may have RJ-12 or - RJ-45 ports.</para> - - <para>See the documentation that accompanied the hardware for - specifications on the kind of port in use. A visual inspection of - the port often works too.</para> - </sect4> - - <sect4 xml:id="term-portnames"> - <title>Port Names</title> - - <para>In FreeBSD, you access each serial port through an entry in - the <filename>/dev</filename> directory. There are two different - kinds of entries:</para> - - <itemizedlist> - <listitem> - <para>Call-in ports are named - <filename>/dev/ttydN</filename> - where <replaceable>N</replaceable> is the port number, - starting from zero. Generally, you use the call-in port for - terminals. Call-in ports require that the serial line assert - the data carrier detect (DCD) signal to work correctly.</para> - </listitem> - - <listitem> - <para>Call-out ports are named - <filename>/dev/cuadN</filename>. - You usually do not use the call-out port for terminals, just - for modems. You may use the call-out port if the serial cable - or the terminal does not support the carrier detect - signal.</para> - - <note><para>Call-out ports are named - <filename>/dev/cuaaN</filename> in - &os; 5.X and older.</para></note> - </listitem> - </itemizedlist> - - <para>If you have connected a terminal to the first serial port - (<filename>COM1</filename> in &ms-dos;), then you will - use <filename>/dev/ttyd0</filename> to refer to the terminal. If - the terminal is on the second serial port (also known as - <filename>COM2</filename>), use - <filename>/dev/ttyd1</filename>, and so forth.</para> - - </sect4> - </sect3> - </sect2> - - <sect2> - <title>Kernel Configuration</title> - - <para>FreeBSD supports four serial ports by default. In the - &ms-dos; world, these are known as - <filename>COM1</filename>, - <filename>COM2</filename>, - <filename>COM3</filename>, and - <filename>COM4</filename>. FreeBSD currently supports - <quote>dumb</quote> multiport serial interface cards, such as - the BocaBoard 1008 and 2016, as well as more - intelligent multi-port cards such as those made by Digiboard - and Stallion Technologies. However, the default kernel only looks - for the standard COM ports.</para> - - <para>To see if your kernel recognizes any of your serial ports, watch - for messages while the kernel is booting, or use the - <command>/sbin/dmesg</command> command to replay the kernel's boot - messages. In particular, look for messages that start with the - characters <literal>sio</literal>.</para> - - <tip><para>To view just the messages that have the word - <literal>sio</literal>, use the command:</para> - - <screen>&prompt.root; <userinput>/sbin/dmesg | grep 'sio'</userinput></screen> - </tip> - - <para>For example, on a system with four serial ports, these are the - serial-port specific kernel boot messages:</para> - - <screen>sio0 at 0x3f8-0x3ff irq 4 on isa -sio0: type 16550A -sio1 at 0x2f8-0x2ff irq 3 on isa -sio1: type 16550A -sio2 at 0x3e8-0x3ef irq 5 on isa -sio2: type 16550A -sio3 at 0x2e8-0x2ef irq 9 on isa -sio3: type 16550A</screen> - - <para>If your kernel does not recognize all of your serial - ports, you will probably need to configure your kernel - in the <filename>/boot/device.hints</filename> file. You can - also comment-out or completely remove lines for devices you do not - have.</para> - - <para>On &os; 4.X you have to edit your kernel configuration file. - For detailed information on configuring your kernel, please see <xref linkend="kernelconfig"/>. The relevant device lines would look like - this:</para> - - <programlisting>device sio0 at isa? port IO_COM1 irq 4 -device sio1 at isa? port IO_COM2 irq 3 -device sio2 at isa? port IO_COM3 irq 5 -device sio3 at isa? port IO_COM4 irq 9</programlisting> - - <para>Please refer to the &man.sio.4; manual page for - more information on serial ports and multiport boards configuration. - Be careful if you are using a configuration - file that was previously used for a different version of - FreeBSD because the device flags and the syntax have changed between - versions.</para> - - <note> - <para><literal>port IO_COM1</literal> is a substitution for - <literal>port 0x3f8</literal>, <literal>IO_COM2</literal> is - <literal>0x2f8</literal>, <literal>IO_COM3</literal> is - <literal>0x3e8</literal>, and <literal>IO_COM4</literal> is - <literal>0x2e8</literal>, which are fairly common port addresses for - their respective serial ports; interrupts 4, 3, 5, and 9 are fairly - common interrupt request lines. Also note that regular serial ports - <emphasis>cannot</emphasis> share interrupts on ISA-bus PCs - (multiport boards have on-board electronics that allow all the - 16550A's on the board to share one or two interrupt request - lines).</para> - </note> - - </sect2> - - <sect2> - <title>Device Special Files</title> - - <para>Most devices in the kernel are accessed through <quote>device - special files</quote>, which are located in the - <filename>/dev</filename> directory. The <filename>sio</filename> - devices are accessed through the - <filename>/dev/ttydN</filename> (dial-in) - and <filename>/dev/cuadN</filename> - (call-out) devices. FreeBSD also provides initialization devices - (<filename>/dev/ttydN.init</filename> and - <filename>/dev/cuadN.init</filename> on - &os; 6.X, - <filename>/dev/ttyidN</filename> and - <filename>/dev/cuaidN</filename> on - &os; 5.X and older) and - locking devices - (<filename>/dev/ttydN.lock</filename> and - <filename>/dev/cuadN.lock</filename> on - &os; 6.X, - <filename>/dev/ttyldN</filename> and - <filename>/dev/cualdN</filename> on - &os; 5.X and older). The - initialization devices are used to initialize communications port - parameters each time a port is opened, such as - <literal>crtscts</literal> for modems which use - <literal>RTS/CTS</literal> signaling for flow control. The locking - devices are used to lock flags on ports to prevent users or programs - changing certain parameters; see the manual pages &man.termios.4;, - &man.sio.4;, and &man.stty.1; for - information on the terminal settings, locking and initializing - devices, and setting terminal options, respectively.</para> - - <sect3> - <title>Making Device Special Files</title> - - <note><para>FreeBSD 5.0 includes the &man.devfs.5; - filesystem which automatically creates device nodes as - needed. If you are running a version of FreeBSD with - <literal>devfs</literal> enabled then you can safely skip - this section.</para></note> - - <para>A shell script called <command>MAKEDEV</command> in the - <filename>/dev</filename> directory manages the device special - files. To use <command>MAKEDEV</command> to make dial-up device - special files for <filename>COM1</filename> (port 0), - <command>cd</command> to <filename>/dev</filename> and issue the - command <command>MAKEDEV ttyd0</command>. Likewise, to make dial-up - device special files for <filename>COM2</filename> (port 1), - use <command>MAKEDEV ttyd1</command>.</para> - - <para><command>MAKEDEV</command> not only creates the - <filename>/dev/ttydN</filename> device - special files, but also the - <filename>/dev/cuaaN</filename>, - <filename>/dev/cuaiaN</filename>, - <filename>/dev/cualaN</filename>, - <filename>/dev/ttyldN</filename>, - and - <filename>/dev/ttyidN</filename> - nodes.</para> - - <para>After making new device special files, be sure to check the - permissions on the files (especially the - <filename>/dev/cua*</filename> files) to make sure that only users - who should have access to those device special files can read and - write on them — you probably do not want to allow your average - user to use your modems to dial-out. The default permissions on the - <filename>/dev/cua*</filename> files should be sufficient:</para> - - <screen>crw-rw---- 1 uucp dialer 28, 129 Feb 15 14:38 /dev/cuaa1 -crw-rw---- 1 uucp dialer 28, 161 Feb 15 14:38 /dev/cuaia1 -crw-rw---- 1 uucp dialer 28, 193 Feb 15 14:38 /dev/cuala1</screen> - - <para>These permissions allow the user <systemitem class="username">uucp</systemitem> and - users in the group <systemitem class="username">dialer</systemitem> to use the call-out - devices.</para> - </sect3> - </sect2> - - - <sect2 xml:id="serial-hw-config"> - <title>Serial Port Configuration</title> - - <indexterm><primary><filename>ttyd</filename></primary></indexterm> - <indexterm><primary><filename>cuad</filename></primary></indexterm> - - <para>The <filename>ttydN</filename> (or - <filename>cuadN</filename>) device is the - regular device you will want to open for your applications. When a - process opens the device, it will have a default set of terminal I/O - settings. You can see these settings with the command</para> - - <screen>&prompt.root; <userinput>stty -a -f /dev/ttyd1</userinput></screen> - - <para>When you change the settings to this device, the settings are in - effect until the device is closed. When it is reopened, it goes back to - the default set. To make changes to the default set, you can open and - adjust the settings of the <quote>initial state</quote> device. For - example, to turn on <option>CLOCAL</option> mode, 8 bit communication, - and <option>XON/XOFF</option> flow control by default for - <filename>ttyd5</filename>, type:</para> - - <screen>&prompt.root; <userinput>stty -f /dev/ttyd5.init clocal cs8 ixon ixoff</userinput></screen> - - <indexterm> - <primary>rc files</primary> - <secondary><filename>rc.serial</filename></secondary> - </indexterm> - - <para>System-wide initialization of the serial devices is - controlled in <filename>/etc/rc.d/serial</filename>. This file - affects the default settings of serial devices.</para> - - <note> - <para>On &os; 4.X, system-wide initialization of the serial devices - is controlled in <filename>/etc/rc.serial</filename>.</para> - </note> - - <para>To prevent certain settings from being changed by an - application, make adjustments to the <quote>lock state</quote> - device. For example, to lock the speed of - <filename>ttyd5</filename> to 57600 bps, type:</para> - - <screen>&prompt.root; <userinput>stty -f /dev/ttyd5.lock 57600</userinput></screen> - - <para>Now, an application that opens - <filename>ttyd5</filename> and tries to change the speed of - the port will be stuck with 57600 bps.</para> - - <indexterm> - <primary><command>MAKEDEV</command></primary> - </indexterm> - <para>Naturally, you should make the initial state and lock state devices - writable only by the <systemitem class="username">root</systemitem> account.</para> - </sect2> - </sect1> - - <sect1 xml:id="term"> - <info><title>Terminals</title> - <authorgroup> - <author><personname><firstname>Sean</firstname><surname>Kelly</surname></personname><contrib>Contributed by </contrib></author> - <!-- 28 July 1996 --> - </authorgroup> - </info> - - - <indexterm><primary>terminals</primary></indexterm> - - <para>Terminals provide a convenient and low-cost way to access - your FreeBSD system when you are not at the computer's console or on - a connected network. This section describes how to use terminals with - FreeBSD.</para> - - <sect2 xml:id="term-uses"> - <title>Uses and Types of Terminals</title> - - <para>The original &unix; systems did not have consoles. Instead, people - logged in and ran programs through terminals that were connected to - the computer's serial ports. It is quite similar to using a modem and - terminal software to dial into a remote system to do text-only - work.</para> - - <para>Today's PCs have consoles capable of high quality graphics, but - the ability to establish a login session on a serial port still exists - in nearly every &unix; style operating system today; FreeBSD is no - exception. By using a terminal attached to an unused serial port, you - can log in and run any text program that you would normally run on the - console or in an <command>xterm</command> window in the X Window - System.</para> - - <para>For the business user, you can attach many terminals to a FreeBSD - system and place them on your employees' desktops. For a home user, a - spare computer such as an older IBM PC or a &macintosh; can be a - terminal wired into a more powerful computer running FreeBSD. You can - turn what might otherwise be a single-user computer into a powerful - multiple user system.</para> - - <para>For FreeBSD, there are three kinds of terminals:</para> - - <itemizedlist> - <listitem> - <para><link linkend="term-dumb">Dumb terminals</link></para> - </listitem> - - <listitem> - <para><link linkend="term-pcs">PCs acting as terminals</link></para> - </listitem> - - <listitem> - <para><link linkend="term-x">X terminals</link></para> - </listitem> - </itemizedlist> - - <para>The remaining subsections describe each kind.</para> - - <sect3 xml:id="term-dumb"> - <title>Dumb Terminals</title> - - <para>Dumb terminals are specialized pieces of hardware that let you - connect to computers over serial lines. They are called - <quote>dumb</quote> because they have only enough computational power - to display, send, and receive text. You cannot run any programs on - them. It is the computer to which you connect them that has all the - power to run text editors, compilers, email, games, and so - forth.</para> - - <para>There are hundreds of kinds of dumb terminals made by many - manufacturers, including Digital Equipment Corporation's VT-100 and - Wyse's WY-75. Just about any kind will work with FreeBSD. Some - high-end terminals can even display graphics, but only certain - software packages can take advantage of these advanced - features.</para> - - <para>Dumb terminals are popular in work environments where workers do - not need access to graphical applications such as those provided by - the X Window System.</para> - </sect3> - - <sect3 xml:id="term-pcs"> - <title>PCs Acting as Terminals</title> - - <para>If a <link linkend="term-dumb">dumb terminal</link> has just - enough ability to display, send, and receive text, then certainly - any spare personal computer can be a dumb terminal. All you need is - the proper cable and some <emphasis>terminal emulation</emphasis> - software to run on the computer.</para> - - <para>Such a configuration is popular in homes. For example, if your - spouse is busy working on your FreeBSD system's console, you can do - some text-only work at the same time from a less powerful personal - computer hooked up as a terminal to the FreeBSD system.</para> - </sect3> - - <sect3 xml:id="term-x"> - <title>X Terminals</title> - - <para>X terminals are the most sophisticated kind of terminal - available. Instead of connecting to a serial port, they usually - connect to a network like Ethernet. Instead of being relegated to - text-only applications, they can display any X application.</para> - - <para>We introduce X terminals just for the sake of completeness. - However, this chapter does <emphasis>not</emphasis> cover setup, - configuration, or use of X terminals.</para> - </sect3> - </sect2> - - <sect2 xml:id="term-config"> - <title>Configuration</title> - - <para>This section describes what you need to configure on your FreeBSD - system to enable a login session on a terminal. It assumes you have - already configured your kernel to support the serial port to which the - terminal is connected—and that you have connected it.</para> - - <para>Recall from <xref linkend="boot"/> that the - <command>init</command> process is responsible for all process - control and initialization at system startup. One of the - tasks performed by <command>init</command> is to read the - <filename>/etc/ttys</filename> file and start a - <command>getty</command> process on the available terminals. - The <command>getty</command> process is responsible for - reading a login name and starting the <command>login</command> - program.</para> - - <para>Thus, to configure terminals for your FreeBSD system the - following steps should be taken as <systemitem class="username">root</systemitem>:</para> - - <procedure> - <step> - <para>Add a line to <filename>/etc/ttys</filename> for the entry in - the <filename>/dev</filename> directory for the serial port if it - is not already there.</para> - </step> - - <step> - <para>Specify that <command>/usr/libexec/getty</command> be run on - the port, and specify the appropriate - <replaceable>getty</replaceable> type from the - <filename>/etc/gettytab</filename> file.</para> - </step> - - <step> - <para>Specify the default terminal type.</para> - </step> - - <step> - <para>Set the port to <quote>on.</quote></para> - </step> - - <step> - <para>Specify whether the port should be - <quote>secure.</quote></para> - </step> - - <step> - <para>Force <command>init</command> to reread the - <filename>/etc/ttys</filename> file.</para> - </step> - </procedure> - - <para>As an optional step, you may wish to create a custom - <replaceable>getty</replaceable> type for use in step 2 by making an - entry in <filename>/etc/gettytab</filename>. This chapter does - not explain how to do so; you are encouraged to see the - &man.gettytab.5; and the &man.getty.8; manual pages for more - information.</para> - - <sect3 xml:id="term-etcttys"> - <title>Adding an Entry to <filename>/etc/ttys</filename></title> - - <para>The <filename>/etc/ttys</filename> file lists all of the ports - on your FreeBSD system where you want to allow logins. For example, - the first virtual console <filename>ttyv0</filename> has an entry in - this file. You can log in on the console using this entry. This - file also contains entries for the other virtual consoles, serial ports, - and pseudo-ttys. For a hardwired terminal, just list the serial - port's <filename>/dev</filename> entry without the - <filename>/dev</filename> part (for example, - <filename>/dev/ttyv0</filename> would be listed as - <filename>ttyv0</filename>).</para> - - <para>A default FreeBSD install includes an - <filename>/etc/ttys</filename> file with support for the first - four serial ports: <filename>ttyd0</filename> through - <filename>ttyd3</filename>. If you are attaching a terminal - to one of those ports, you do not need to add another entry.</para> - - <example xml:id="ex-etc-ttys"> - <title>Adding Terminal Entries to - <filename>/etc/ttys</filename></title> - - <para>Suppose we would like to connect two terminals to the - system: a Wyse-50 and an old 286 IBM PC running - <application>Procomm</application> terminal software - emulating a VT-100 terminal. We connect the Wyse to the - second serial port and the 286 to the sixth serial port (a - port on a multiport serial card). The corresponding - entries in the <filename>/etc/ttys</filename> file would - look like this:</para> - - <programlisting>ttyd1<co xml:id="co-ttys-line1col1"/> "/usr/libexec/getty std.38400"<co xml:id="co-ttys-line1col2"/> wy50<co xml:id="co-ttys-line1col3"/> on<co xml:id="co-ttys-line1col4"/> insecure<co xml:id="co-ttys-line1col5"/> -ttyd5 "/usr/libexec/getty std.19200" vt100 on insecure - </programlisting> - - <calloutlist> - <callout arearefs="co-ttys-line1col1"> - <para>The first field normally specifies the name of - the terminal special file as it is found in - <filename>/dev</filename>.</para> - </callout> - <callout arearefs="co-ttys-line1col2"> - - <para>The second field is the command to execute for - this line, which is usually &man.getty.8;. - <command>getty</command> initializes and opens the - line, sets the speed, prompts for a user name and then - executes the &man.login.1; program.</para> - - <para>The <command>getty</command> program accepts one - (optional) parameter on its command line, the - <replaceable>getty</replaceable> type. A - <replaceable>getty</replaceable> type configures - characteristics on the terminal line, like bps rate - and parity. The <command>getty</command> program reads - these characteristics from the file - <filename>/etc/gettytab</filename>.</para> - - <para>The file <filename>/etc/gettytab</filename> - contains lots of entries for terminal lines both old - and new. In almost all cases, the entries that start - with the text <literal>std</literal> will work for - hardwired terminals. These entries ignore parity. - There is a <literal>std</literal> entry for each bps - rate from 110 to 115200. Of course, you can add your - own entries to this file. The &man.gettytab.5; manual - page provides more information.</para> - - <para>When setting the <replaceable>getty</replaceable> - type in the <filename>/etc/ttys</filename> file, make - sure that the communications settings on the terminal - match.</para> - - <para>For our example, the Wyse-50 uses no parity and - connects at 38400 bps. The 286 PC uses no parity and - connects at 19200 bps.</para> - - </callout> - - <callout arearefs="co-ttys-line1col3"> - - <para>The third field is the type of terminal usually - connected to that tty line. For dial-up ports, - <literal>unknown</literal> or - <literal>dialup</literal> is typically used in this - field since users may dial up with practically any - type of terminal or software. For hardwired - terminals, the terminal type does not change, so you - can put a real terminal type from the &man.termcap.5; - database file in this field.</para> - - <para>For our example, the Wyse-50 uses the real - terminal type while the 286 PC running - <application>Procomm</application> will be set to - emulate at VT-100. </para> - - </callout> - - <callout arearefs="co-ttys-line1col4"> - <para>The fourth field specifies if the port should be - enabled. Putting <literal>on</literal> here will have - the <command>init</command> process start the program - in the second field, <command>getty</command>. If you - put <literal>off</literal> in this field, there will - be no <command>getty</command>, and hence no logins on - the port.</para> - </callout> - - <callout arearefs="co-ttys-line1col5"> - <para>The final field is used to specify whether the - port is secure. Marking a port as secure means that - you trust it enough to allow the - <systemitem class="username">root</systemitem> account (or any account with - a user ID of 0) to login from that port. Insecure - ports do not allow <systemitem class="username">root</systemitem> logins. - On an insecure port, users must login from - unprivileged accounts and then use &man.su.1; or a - similar mechanism to gain superuser privileges.</para> - - <para>It is highly recommended that you use - <quote>insecure</quote> - even for terminals that are behind locked doors. It - is quite easy to login and use <command>su</command> - if you need superuser privileges.</para> - </callout> - </calloutlist> - </example> - </sect3> - - <sect3 xml:id="term-hup"> - <title>Force <command>init</command> to Reread - <filename>/etc/ttys</filename></title> - - <para>After making the necessary changes to the - <filename>/etc/ttys</filename> file you should send a SIGHUP - (hangup) signal to the <command>init</command> process to - force it to re-read its configuration file. For example:</para> - - <screen>&prompt.root; <userinput>kill -HUP 1</userinput></screen> - - <note> - <para><command>init</command> is always the first process run - on a system, therefore it will always have PID 1.</para> - </note> - - <para>If everything is set up correctly, all cables are in - place, and the terminals are powered up, then a - <command>getty</command> process should be running on each - terminal and you should see login prompts on your terminals - at this point.</para> - </sect3> - </sect2> - - <sect2 xml:id="term-debug"> - <title>Troubleshooting Your Connection</title> - - <para>Even with the most meticulous attention to detail, something could - still go wrong while setting up a terminal. Here is a list of - symptoms and some suggested fixes.</para> - - <sect3> - <title>No Login Prompt Appears</title> - - <para>Make sure the terminal is plugged in and powered up. If it - is a personal computer acting as a terminal, make sure it is - running terminal emulation software on the correct serial - port.</para> - - <para>Make sure the cable is connected firmly to both the terminal - and the FreeBSD computer. Make sure it is the right kind of - cable.</para> - - <para>Make sure the terminal and FreeBSD agree on the bps rate and - parity settings. If you have a video display terminal, make - sure the contrast and brightness controls are turned up. If it - is a printing terminal, make sure paper and ink are in good - supply.</para> - - <para>Make sure that a <command>getty</command> process is running - and serving the terminal. For example, to get a list of - running <command>getty</command> processes with - <command>ps</command>, type:</para> - - <screen>&prompt.root; <userinput>ps -axww|grep getty</userinput></screen> - - <para>You should see an entry for the terminal. For - example, the following display shows that a - <command>getty</command> is running on the second serial - port <literal>ttyd1</literal> and is using the - <literal>std.38400</literal> entry in - <filename>/etc/gettytab</filename>:</para> - - <screen>22189 d1 Is+ 0:00.03 /usr/libexec/getty std.38400 ttyd1</screen> - - <para>If no <command>getty</command> process is running, make sure - you have enabled the port in <filename>/etc/ttys</filename>. - Also remember to run <command>kill -HUP 1</command> - after modifying the <filename>ttys</filename> file.</para> - - <para>If the <command>getty</command> process is running - but the terminal still does not display a login prompt, - or if it displays a prompt but will not allow you to - type, your terminal or cable may not support hardware - handshaking. Try changing the entry in - <filename>/etc/ttys</filename> from - <literal>std.38400</literal> to - <literal>3wire.38400</literal> remember to run - <command>kill -HUP 1</command> after modifying - <filename>/etc/ttys</filename>). The - <literal>3wire</literal> entry is similar to - <literal>std</literal>, but ignores hardware - handshaking. You may need to reduce the baud rate or - enable software flow control when using - <literal>3wire</literal> to prevent buffer - overflows.</para> - - </sect3> - - <sect3> - <title>If Garbage Appears Instead of a Login Prompt</title> - - <para>Make sure the terminal and FreeBSD agree on the bps rate and - parity settings. Check the <command>getty</command> processes - to make sure the - correct <replaceable>getty</replaceable> type is in use. If - not, edit <filename>/etc/ttys</filename> and run <command>kill - -HUP 1</command>.</para> - - </sect3> - - <sect3> - <title>Characters Appear Doubled; the Password Appears When Typed</title> - - <para>Switch the terminal (or the terminal emulation software) - from <quote>half duplex</quote> or <quote>local echo</quote> to - <quote>full duplex.</quote></para> - - </sect3> - </sect2> - </sect1> - - <sect1 xml:id="dialup"> - <info><title>Dial-in Service</title> - <authorgroup> - <author><personname><firstname>Guy</firstname><surname>Helmer</surname></personname><contrib>Contributed by </contrib></author> - </authorgroup> - <authorgroup> - <author><personname><firstname>Sean</firstname><surname>Kelly</surname></personname><contrib>Additions by </contrib></author> - </authorgroup> - </info> - - <indexterm><primary>dial-in service</primary></indexterm> - - <para>Configuring your FreeBSD system for dial-in service is very - similar to connecting terminals except that you are dealing with - modems instead of terminals.</para> - - <sect2> - <title>External vs. Internal Modems</title> - - <para>External modems seem to be more convenient for dial-up, because - external modems often can be semi-permanently configured via - parameters stored in non-volatile RAM and they usually provide - lighted indicators that display the state of important RS-232 - signals. Blinking lights impress visitors, but lights are also very - useful to see whether a modem is operating properly.</para> - - <para>Internal modems usually lack non-volatile RAM, so their - configuration may be limited only to setting DIP switches. If your - internal modem has any signal indicator lights, it is probably - difficult to view the lights when the system's cover is in - place.</para> - - <sect3> - <title>Modems and Cables</title> - <indexterm><primary>modem</primary></indexterm> - - <para>If you are using an external modem, then you will of - course need the proper cable. A standard RS-232C serial - cable should suffice as long as all of the normal signals - are wired:</para> - - <table frame="none" pgwide="1" xml:id="serialcomms-signal-names"> - <title>Signal Names</title> - - <tgroup cols="2"> - <thead> - <row> - <entry align="left">Acronyms</entry> - <entry align="left">Names</entry> - </row> - </thead> - - <tbody> - <row> - <entry><acronym>RD</acronym></entry> - <entry>Received Data</entry> - </row> - - <row> - <entry><acronym>TD</acronym></entry> - <entry>Transmitted Data</entry> - </row> - - <row> - <entry><acronym>DTR</acronym></entry> - <entry>Data Terminal Ready</entry> - </row> - - <row> - <entry><acronym>DSR</acronym></entry> - <entry>Data Set Ready</entry> - </row> - - <row> - <entry><acronym>DCD</acronym></entry> - <entry>Data Carrier Detect (RS-232's Received Line - Signal Detector)</entry> - </row> - - <row> - <entry><acronym>SG</acronym></entry> - <entry>Signal Ground</entry> - </row> - - <row> - <entry><acronym>RTS</acronym></entry> - <entry>Request to Send</entry> - </row> - - <row> - <entry><acronym>CTS</acronym></entry> - <entry>Clear to Send</entry> - </row> - </tbody> - </tgroup> - </table> - - <para>FreeBSD needs the <acronym>RTS</acronym> and - <acronym>CTS</acronym> signals for flow control at speeds above - 2400 bps, the <acronym>CD</acronym> signal to detect when a call has - been answered or the line has been hung up, and the - <acronym>DTR</acronym> signal to reset the modem after a session is - complete. Some cables are wired without all of the needed signals, - so if you have problems, such as a login session not going away when - the line hangs up, you may have a problem with your cable.</para> - - <para>Like other &unix; like operating systems, FreeBSD uses the - hardware signals to find out when a call has been answered - or a line has been hung up and to hangup and reset the modem - after a call. FreeBSD avoids sending commands to the modem - or watching for status reports from the modem. If you are - familiar with connecting modems to PC-based bulletin board - systems, this may seem awkward.</para> - </sect3> - </sect2> - - <sect2> - <title>Serial Interface Considerations</title> - - <para>FreeBSD supports NS8250-, NS16450-, NS16550-, and NS16550A-based - EIA RS-232C (CCITT V.24) communications interfaces. The 8250 and - 16450 devices have single-character buffers. The 16550 device - provides a 16-character buffer, which allows for better system - performance. (Bugs in plain 16550's prevent the use of the - 16-character buffer, so use 16550A's if possible). Because - single-character-buffer devices require more work by the operating - system than the 16-character-buffer devices, 16550A-based serial - interface cards are much preferred. If the system has many active - serial ports or will have a heavy load, 16550A-based cards are - better for low-error-rate communications.</para> - </sect2> - - <sect2> - <title>Quick Overview</title> - - <indexterm><primary>getty</primary></indexterm> - <para>As with terminals, <command>init</command> spawns a - <command>getty</command> process for each configured serial - port for dial-in connections. For example, if a modem is - attached to <filename>/dev/ttyd0</filename>, the command - <command>ps ax</command> might show this:</para> - - <screen> 4850 ?? I 0:00.09 /usr/libexec/getty V19200 ttyd0</screen> - - <para>When a user dials the modem's line and the modems connect, the - <acronym>CD</acronym> (Carrier Detect) line is reported by the modem. - The kernel - notices that carrier has been detected and completes - <command>getty</command>'s open of the port. <command>getty</command> - sends a <prompt>login:</prompt> prompt at the specified initial line - speed. <command>getty</command> watches to see if legitimate - characters are received, and, in a typical configuration, if it finds - junk (probably due to the modem's connection speed being different - than <command>getty</command>'s speed), <command>getty</command> tries - adjusting the line speeds until it receives reasonable - characters.</para> - - <indexterm> - <primary><command>/usr/bin/login</command></primary> - </indexterm> - <para>After the user enters his/her login name, - <command>getty</command> executes - <filename>/usr/bin/login</filename>, which completes the login - by asking for the user's password and then starting the user's - shell.</para> - </sect2> - - - <sect2> - <title>Configuration Files</title> - - <para>There are three system configuration files in the - <filename>/etc</filename> directory that you will probably need to - edit to allow dial-up access to your FreeBSD system. The first, - <filename>/etc/gettytab</filename>, contains configuration information - for the <filename>/usr/libexec/getty</filename> daemon. Second, - <filename>/etc/ttys</filename> holds information that tells - <filename>/sbin/init</filename> what <filename>tty</filename> devices - should have <command>getty</command> processes running on them. - Lastly, you can place port initialization commands in the - <filename>/etc/rc.d/serial</filename> script.</para> - - <para>There are two schools of thought regarding dial-up modems on &unix;. - One group likes to configure their modems and systems so that no matter - at what speed a remote user dials in, the local computer-to-modem - RS-232 interface runs at a locked speed. The benefit of this - configuration is that the remote user always sees a system login - prompt immediately. The downside is that the system does not know - what a user's true data rate is, so full-screen programs like Emacs - will not adjust their screen-painting methods to make their response - better for slower connections.</para> - - <para>The other school configures their modems' RS-232 interface to vary - its speed based on the remote user's connection speed. For example, - V.32bis (14.4 Kbps) connections to the modem might make the modem run - its RS-232 interface at 19.2 Kbps, while 2400 bps connections make the - modem's RS-232 interface run at 2400 bps. Because - <command>getty</command> does not understand any particular modem's - connection speed reporting, <command>getty</command> gives a - <prompt>login:</prompt> message at an initial speed and watches the - characters that come back in response. If the user sees junk, it is - assumed that they know they should press the - <keycode>Enter</keycode> key until they see a recognizable - prompt. If the data rates do not match, <command>getty</command> sees - anything the user types as <quote>junk</quote>, tries going to the next - speed and gives the <prompt>login:</prompt> prompt again. This - procedure can continue ad nauseam, but normally only takes a keystroke - or two before the user sees a good prompt. Obviously, this login - sequence does not look as clean as the former - <quote>locked-speed</quote> method, but a user on a low-speed - connection should receive better interactive response from full-screen - programs.</para> - - <para>This section will try to give balanced configuration information, - but is biased towards having the modem's data rate follow the - connection rate.</para> - - <sect3> - <title><filename>/etc/gettytab</filename></title> - - <indexterm> - <primary><filename>/etc/gettytab</filename></primary> - </indexterm> - <para><filename>/etc/gettytab</filename> is a &man.termcap.5;-style - file of configuration information for &man.getty.8;. Please see the - &man.gettytab.5; manual page for complete information on the - format of the file and the list of capabilities.</para> - - <sect4> - <title>Locked-speed Config</title> - - <para>If you are locking your modem's data communications rate at a - particular speed, you probably will not need to make any changes - to <filename>/etc/gettytab</filename>.</para> - </sect4> - - <sect4> - <title>Matching-speed Config</title> - - <para>You will need to set up an entry in - <filename>/etc/gettytab</filename> to give - <command>getty</command> information about the speeds you wish to - use for your modem. If you have a 2400 bps modem, you can - probably use the existing <literal>D2400</literal> entry.</para> - - <programlisting># -# Fast dialup terminals, 2400/1200/300 rotary (can start either way) -# -D2400|d2400|Fast-Dial-2400:\ - :nx=D1200:tc=2400-baud: -3|D1200|Fast-Dial-1200:\ - :nx=D300:tc=1200-baud: -5|D300|Fast-Dial-300:\ - :nx=D2400:tc=300-baud:</programlisting> - - <para>If you have a higher speed modem, you will probably need to - add an entry in <filename>/etc/gettytab</filename>; here is an - entry you could use for a 14.4 Kbps modem with a top interface - speed of 19.2 Kbps:</para> - - <programlisting># -# Additions for a V.32bis Modem -# -um|V300|High Speed Modem at 300,8-bit:\ - :nx=V19200:tc=std.300: -un|V1200|High Speed Modem at 1200,8-bit:\ - :nx=V300:tc=std.1200: -uo|V2400|High Speed Modem at 2400,8-bit:\ - :nx=V1200:tc=std.2400: -up|V9600|High Speed Modem at 9600,8-bit:\ - :nx=V2400:tc=std.9600: -uq|V19200|High Speed Modem at 19200,8-bit:\ - :nx=V9600:tc=std.19200:</programlisting> - - <para>This will result in 8-bit, no parity connections.</para> - - <para>The example above starts the communications rate at 19.2 Kbps - (for a V.32bis connection), then cycles through 9600 bps (for - V.32), 2400 bps, 1200 bps, 300 bps, and back to 19.2 Kbps. - Communications rate cycling is implemented with the - <literal>nx=</literal> (<quote>next table</quote>) capability. - Each of the lines uses a <literal>tc=</literal> (<quote>table - continuation</quote>) entry to pick up the rest of the - <quote>standard</quote> settings for a particular data rate.</para> - - <para>If you have a 28.8 Kbps modem and/or you want to take - advantage of compression on a 14.4 Kbps modem, you need to use a - higher communications rate than 19.2 Kbps. Here is an example of - a <filename>gettytab</filename> entry starting a 57.6 Kbps:</para> - - <programlisting># -# Additions for a V.32bis or V.34 Modem -# Starting at 57.6 Kbps -# -vm|VH300|Very High Speed Modem at 300,8-bit:\ - :nx=VH57600:tc=std.300: -vn|VH1200|Very High Speed Modem at 1200,8-bit:\ - :nx=VH300:tc=std.1200: -vo|VH2400|Very High Speed Modem at 2400,8-bit:\ - :nx=VH1200:tc=std.2400: -vp|VH9600|Very High Speed Modem at 9600,8-bit:\ - :nx=VH2400:tc=std.9600: -vq|VH57600|Very High Speed Modem at 57600,8-bit:\ - :nx=VH9600:tc=std.57600:</programlisting> - - <para>If you have a slow CPU or a heavily loaded system and do - not have 16550A-based serial ports, you may receive - <errorname>sio</errorname> - <quote>silo</quote> errors at 57.6 Kbps.</para> - </sect4> - </sect3> - - <sect3 xml:id="dialup-ttys"> - <title><filename>/etc/ttys</filename></title> - <indexterm> - <primary><filename>/etc/ttys</filename></primary> - </indexterm> - - <para>Configuration of the <filename>/etc/ttys</filename> file - was covered in <xref linkend="ex-etc-ttys"/>. - Configuration for modems is similar but we must pass a - different argument to <command>getty</command> and specify a - different terminal type. The general format for both - locked-speed and matching-speed configurations is:</para> - - <programlisting>ttyd0 "/usr/libexec/getty <replaceable>xxx</replaceable>" dialup on</programlisting> - - <para>The first item in the above line is the device special file for - this entry — <literal>ttyd0</literal> means - <filename>/dev/ttyd0</filename> is the file that this - <command>getty</command> will be watching. The second item, - <literal>"/usr/libexec/getty - xxx"</literal> - (<replaceable>xxx</replaceable> will be replaced by the initial - <filename>gettytab</filename> capability) is the process - <command>init</command> will run on the device. The third item, - <literal>dialup</literal>, is the default terminal type. The fourth - parameter, <literal>on</literal>, indicates to - <command>init</command> that the line is operational. There can be - a fifth parameter, <literal>secure</literal>, but it should only be - used for terminals which are physically secure (such as the system - console).</para> - - <para>The default terminal type (<literal>dialup</literal> in the - example above) may depend on local preferences. - <literal>dialup</literal> is the traditional default terminal type - on dial-up lines so that users may customize their login scripts to - notice when the terminal is <literal>dialup</literal> and - automatically adjust their terminal type. However, the author finds - it easier at his site to specify <literal>vt102</literal> as the - default terminal type, since the users just use VT102 emulation on - their remote systems.</para> - - <para>After you have made changes to <filename>/etc/ttys</filename>, - you may send the <command>init</command> process a - <acronym>HUP</acronym> signal to re-read the file. You can use the - command - - <screen>&prompt.root; <userinput>kill -HUP 1</userinput></screen> - - to send the signal. If this is your first time setting up the - system, you may want to wait until your modem(s) are properly - configured and connected before signaling <command>init</command>. - </para> - - <sect4> - <title>Locked-speed Config</title> - - <para>For a locked-speed configuration, your - <filename>ttys</filename> entry needs to have a fixed-speed entry - provided to <command>getty</command>. For a modem whose port - speed is locked at 19.2 Kbps, the <filename>ttys</filename> entry - might look like this:</para> - - <programlisting>ttyd0 "/usr/libexec/getty std.19200" dialup on</programlisting> - - <para>If your modem is locked at a different data rate, - substitute the appropriate value for - <literal>std.speed</literal> - instead of <literal>std.19200</literal>. Make sure that - you use a valid type listed in - <filename>/etc/gettytab</filename>.</para> - </sect4> - - <sect4> - <title>Matching-speed Config</title> - - <para>In a matching-speed configuration, your - <filename>ttys</filename> entry needs to reference the appropriate - beginning <quote>auto-baud</quote> (sic) entry in - <filename>/etc/gettytab</filename>. For example, if you added the - above suggested entry for a matching-speed modem that starts at - 19.2 Kbps (the <filename>gettytab</filename> entry containing the - <literal>V19200</literal> starting point), your - <filename>ttys</filename> entry might look like this:</para> - - <programlisting>ttyd0 "/usr/libexec/getty V19200" dialup on</programlisting> - </sect4> - </sect3> - - <sect3> - <title><filename>/etc/rc.d/serial</filename></title> - <indexterm> - <primary>rc files</primary> - <secondary><filename>rc.serial</filename></secondary> - </indexterm> - - <para>High-speed modems, like V.32, V.32bis, and V.34 modems, - need to use hardware (<literal>RTS/CTS</literal>) flow - control. You can add <command>stty</command> commands to - <filename>/etc/rc.d/serial</filename> to set the hardware flow - control flag in the FreeBSD kernel for the modem - ports.</para> - - <para>For example to set the <literal>termios</literal> flag - <varname>crtscts</varname> on serial port #1's - (<filename>COM2</filename>) dial-in and dial-out initialization - devices, the following lines could be added to - <filename>/etc/rc.d/serial</filename>:</para> - <programlisting># Serial port initial configuration -stty -f /dev/ttyd1.init crtscts -stty -f /dev/cuad1.init crtscts</programlisting> - - </sect3> - </sect2> - - <sect2> - <title>Modem Settings</title> - - <para>If you have a modem whose parameters may be permanently set in - non-volatile RAM, you will need to use a terminal program (such as - Telix under &ms-dos; or <command>tip</command> under FreeBSD) to set the - parameters. Connect to the modem using the same communications speed - as the initial speed <command>getty</command> will use and configure - the modem's non-volatile RAM to match these requirements:</para> - - <itemizedlist> - <listitem> - <para><acronym>CD</acronym> asserted when connected</para> - </listitem> - - <listitem> - <para><acronym>DTR</acronym> asserted for operation; dropping DTR - hangs up line and resets modem</para> - </listitem> - - <listitem> - <para><acronym>CTS</acronym> transmitted data flow control</para> - </listitem> - - <listitem> - <para>Disable <acronym>XON/XOFF</acronym> flow control</para> - </listitem> - - <listitem> - <para><acronym>RTS</acronym> received data flow control</para> - </listitem> - - <listitem> - <para>Quiet mode (no result codes)</para> - </listitem> - - <listitem> - <para>No command echo</para> - </listitem> - </itemizedlist> - - <para>Please read the documentation for your modem to find out what - commands and/or DIP switch settings you need to give it.</para> - - <para>For example, to set the above parameters on a &usrobotics; - &sportster; 14,400 external modem, one could give these commands to - the modem:</para> - - <programlisting>ATZ -AT&C1&D2&H1&I0&R2&W</programlisting> - - <para>You might also want to take this opportunity to adjust other - settings in the modem, such as whether it will use V.42bis and/or MNP5 - compression.</para> - - <para>The &usrobotics; &sportster; 14,400 external modem also has some DIP switches - that need to be set; for other modems, perhaps you can use these - settings as an example:</para> - - <itemizedlist> - <listitem> - <para>Switch 1: UP — DTR Normal</para> - </listitem> - - <listitem> - <para>Switch 2: N/A (Verbal Result Codes/Numeric Result - Codes)</para> - </listitem> - - <listitem> - <para>Switch 3: UP — Suppress Result Codes</para> - </listitem> - - <listitem> - <para>Switch 4: DOWN — No echo, offline commands</para> - </listitem> - - <listitem> - <para>Switch 5: UP — Auto Answer</para> - </listitem> - - <listitem> - <para>Switch 6: UP — Carrier Detect Normal</para> - </listitem> - - <listitem> - <para>Switch 7: UP — Load NVRAM Defaults</para> - </listitem> - - <listitem> - <para>Switch 8: N/A (Smart Mode/Dumb Mode)</para> - </listitem> - </itemizedlist> - - <para>Result codes should be disabled/suppressed for dial-up modems to - avoid problems that can occur if <command>getty</command> mistakenly - gives a <prompt>login:</prompt> prompt to a modem that is in command - mode and the modem echoes the command or returns a result - code. This sequence can result in a extended, silly conversation - between <command>getty</command> and the modem.</para> - - <sect3> - <title>Locked-speed Config</title> - - <para>For a locked-speed configuration, you will need to configure the - modem to maintain a constant modem-to-computer data rate independent - of the communications rate. On a &usrobotics; &sportster; 14,400 external - modem, these commands will lock the modem-to-computer data rate at - the speed used to issue the commands:</para> - - <programlisting>ATZ -AT&B1&W</programlisting> - </sect3> - - <sect3> - <title>Matching-speed Config</title> - - <para>For a variable-speed configuration, you will need to configure - your modem to adjust its serial port data rate to match the incoming - call rate. On a &usrobotics; &sportster; 14,400 external modem, these commands - will lock the modem's error-corrected data rate to the speed used to - issue the commands, but allow the serial port rate to vary for - non-error-corrected connections:</para> - - <programlisting>ATZ -AT&B2&W</programlisting> - </sect3> - - <sect3> - <title>Checking the Modem's Configuration</title> - - <para>Most high-speed modems provide commands to view the modem's - current operating parameters in a somewhat human-readable fashion. - On the &usrobotics; &sportster; 14,400 external modems, the command - <command>ATI5</command> displays the settings that are stored in the - non-volatile RAM. To see the true operating parameters of the modem - (as influenced by the modem's DIP switch settings), use the commands - <command>ATZ</command> and then <command>ATI4</command>.</para> - - <para>If you have a different brand of modem, check your modem's - manual to see how to double-check your modem's configuration - parameters.</para> - </sect3> - </sect2> - - <sect2> - <title>Troubleshooting</title> - - <para>Here are a few steps you can follow to check out the dial-up modem - on your system.</para> - - <sect3> - <title>Checking Out the FreeBSD System</title> - - <para>Hook up your modem to your FreeBSD system, boot the system, and, - if your modem has status indication lights, watch to see whether the - modem's <acronym>DTR</acronym> indicator lights when the - <prompt>login:</prompt> prompt appears on the system's console - — if it lights up, that should mean that FreeBSD has started a - <command>getty</command> process on the appropriate communications - port and is waiting for the modem to accept a call.</para> - - <para>If the <acronym>DTR</acronym> indicator does not light, login to - the FreeBSD system through the console and issue a <command>ps - ax</command> to see if FreeBSD is trying to run a - <command>getty</command> process on the correct port. You should see - lines like these among the processes displayed:</para> - - <screen> 114 ?? I 0:00.10 /usr/libexec/getty V19200 ttyd0 - 115 ?? I 0:00.10 /usr/libexec/getty V19200 ttyd1</screen> - - <para>If you see something different, like this:</para> - - <screen> 114 d0 I 0:00.10 /usr/libexec/getty V19200 ttyd0</screen> - - <para>and the modem has not accepted a call yet, this means that - <command>getty</command> has completed its open on the - communications port. This could indicate a problem with the cabling - or a mis-configured modem, because <command>getty</command> should - not be able to open the communications port until - <acronym>CD</acronym> (carrier detect) has been asserted by the - modem.</para> - - <para>If you do not see any <command>getty</command> processes waiting - to open the desired - <filename>ttydN</filename> port, - double-check your entries in <filename>/etc/ttys</filename> to see - if there are any mistakes there. Also, check the log file - <filename>/var/log/messages</filename> to see if there are any log - messages from <command>init</command> or <command>getty</command> - regarding any problems. If there are any messages, triple-check the - configuration files <filename>/etc/ttys</filename> and - <filename>/etc/gettytab</filename>, as well as the appropriate - device special files <filename>/dev/ttydN</filename>, for any - mistakes, missing entries, or missing device special files.</para> - </sect3> - - <sect3> - <title>Try Dialing In</title> - - <para>Try dialing into the system; be sure to use 8 bits, no parity, - and 1 - stop bit on the remote system. If you do not get a prompt right - away, or get garbage, try pressing <keycode>Enter</keycode> - about once per second. If you still do not see a - <prompt>login:</prompt> prompt after a while, try sending a - <command>BREAK</command>. If you are using a high-speed modem to do - the dialing, try dialing again after locking the dialing modem's - interface speed (via <command>AT&B1</command> on a &usrobotics; - &sportster; modem, for example).</para> - - <para>If you still cannot get a <prompt>login:</prompt> prompt, check - <filename>/etc/gettytab</filename> again and double-check - that</para> - - <itemizedlist> - <listitem> - <para>The initial capability name specified in - <filename>/etc/ttys</filename> for the line matches a name of a - capability in <filename>/etc/gettytab</filename></para> - </listitem> - - <listitem> - <para>Each <literal>nx=</literal> entry matches another - <filename>gettytab</filename> capability name</para> - </listitem> - - <listitem> - <para>Each <literal>tc=</literal> entry matches another - <filename>gettytab</filename> capability name</para> - </listitem> - </itemizedlist> - - <para>If you dial but the modem on the FreeBSD system will not answer, - make sure that the modem is configured to answer the phone when - <acronym>DTR</acronym> is asserted. If the modem seems to be - configured correctly, verify that the <acronym>DTR</acronym> line is - asserted by checking the modem's indicator lights (if it has - any).</para> - - <para>If you have gone over everything several times and it still does - not work, take a break and come back to it later. If it still does - not work, perhaps you can send an electronic mail message to the - &a.questions; describing your modem and your problem, and the good - folks on the list will try to help.</para> - </sect3> - </sect2> - - </sect1> - - <sect1 xml:id="dialout"> - <title>Dial-out Service</title> - <indexterm><primary>dial-out service</primary></indexterm> - - <para>The following are tips for getting your host to be able to connect - over the modem to another computer. This is appropriate for - establishing a terminal session with a remote host.</para> - - <para>This is useful to log onto a BBS.</para> - - <para>This kind of connection can be extremely helpful to get a file on - the Internet if you have problems with PPP. If you need to FTP - something and PPP is broken, use the terminal session to FTP it. Then - use zmodem to transfer it to your machine.</para> - - <sect2> - <title>My Stock Hayes Modem Is Not Supported, What Can I Do?</title> - - <para>Actually, the manual page for <command>tip</command> is out of date. - There is a generic Hayes dialer already built in. Just use - <literal>at=hayes</literal> in your <filename>/etc/remote</filename> - file.</para> - - <para>The Hayes driver is not smart enough to recognize some of the - advanced features of newer modems—messages like - <literal>BUSY</literal>, <literal>NO DIALTONE</literal>, or - <literal>CONNECT 115200</literal> will just confuse it. You should - turn those messages off when you use <command>tip</command> (using - <command>ATX0&W</command>).</para> - - <para>Also, the dial timeout for <command>tip</command> is 60 seconds. - Your modem should use something less, or else tip will think there is - a communication problem. Try <command>ATS7=45&W</command>.</para> - - <note> - <para>As shipped, <command>tip</command> does not yet support - Hayes modems fully. The solution is to edit the file - <filename>tipconf.h</filename> in the directory - <filename>/usr/src/usr.bin/tip/tip</filename>. Obviously you need the - source distribution to do this.</para> - - <para>Edit the line <literal>#define HAYES 0</literal> to - <literal>#define HAYES 1</literal>. Then <command>make</command> and - <command>make install</command>. Everything works nicely after - that.</para> - </note> - </sect2> - - <sect2 xml:id="direct-at"> - <title>How Am I Expected to Enter These AT Commands?</title> - - <indexterm> - <primary><filename>/etc/remote</filename></primary> - </indexterm> - <para>Make what is called a <quote>direct</quote> entry in your - <filename>/etc/remote</filename> file. For example, if your modem is - hooked up to the first serial port, <filename>/dev/cuad0</filename>, - then put in the following line:</para> - - <programlisting>cuad0:dv=/dev/cuad0:br#19200:pa=none</programlisting> - - <para>Use the highest bps rate your modem supports in the br capability. - Then, type <command>tip cuad0</command> and you will be connected to - your modem.</para> - - <para>Or use <command>cu</command> as <systemitem class="username">root</systemitem> with the - following command:</para> - - <screen>&prompt.root; <userinput>cu -lline -sspeed</userinput></screen> - - <para><replaceable>line</replaceable> is the serial port - (e.g.<filename>/dev/cuad0</filename>) and - <replaceable>speed</replaceable> is the speed - (e.g.<literal>57600</literal>). When you are done entering the AT - commands hit <keycap>~.</keycap> to exit.</para> - </sect2> - - <sect2> - <title>The <literal>@</literal> Sign for the pn Capability Does Not - Work!</title> - - <para>The <literal>@</literal> sign in the phone number capability tells - tip to look in <filename>/etc/phones</filename> for a phone number. - But the <literal>@</literal> sign is also a special character in - capability files like <filename>/etc/remote</filename>. Escape it - with a backslash:</para> - - <programlisting>pn=\@</programlisting> - </sect2> - - <sect2> - <title>How Can I Dial a Phone Number on the Command Line?</title> - - <para>Put what is called a <quote>generic</quote> entry in your - <filename>/etc/remote</filename> file. For example:</para> - - <programlisting>tip115200|Dial any phone number at 115200 bps:\ - :dv=/dev/cuad0:br#115200:at=hayes:pa=none:du: -tip57600|Dial any phone number at 57600 bps:\ - :dv=/dev/cuad0:br#57600:at=hayes:pa=none:du:</programlisting> - - <para>Then you can do things like:</para> - - <screen>&prompt.root; <userinput>tip -115200 5551234</userinput></screen> - - <para>If you prefer <command>cu</command> over <command>tip</command>, - use a generic <literal>cu</literal> entry:</para> - - <programlisting>cu115200|Use cu to dial any number at 115200bps:\ - :dv=/dev/cuad1:br#57600:at=hayes:pa=none:du:</programlisting> - - <para>and type:</para> - - <screen>&prompt.root; <userinput>cu 5551234 -s 115200</userinput></screen> - </sect2> - - <sect2> - <title>Do I Have to Type in the bps Rate Every Time I Do That?</title> - - <para>Put in an entry for <literal>tip1200</literal> or - <literal>cu1200</literal>, but go ahead and use whatever bps rate is - appropriate with the br capability. <command>tip</command> thinks a - good default is 1200 bps which is why it looks for a - <literal>tip1200</literal> entry. You do not have to use 1200 bps, - though.</para> - </sect2> - - <sect2> - <title>I Access a Number of Hosts Through a Terminal Server</title> - - <para>Rather than waiting until you are connected and typing - <command>CONNECT <host></command> each time, use tip's - <literal>cm</literal> capability. For example, these entries in - <filename>/etc/remote</filename>:</para> - - <programlisting>pain|pain.deep13.com|Forrester's machine:\ - :cm=CONNECT pain\n:tc=deep13: -muffin|muffin.deep13.com|Frank's machine:\ - :cm=CONNECT muffin\n:tc=deep13: -deep13:Gizmonics Institute terminal server:\ - :dv=/dev/cuad2:br#38400:at=hayes:du:pa=none:pn=5551234:</programlisting> - - <para>will let you type <command>tip pain</command> or <command>tip - muffin</command> to connect to the hosts pain or muffin, and - <command>tip deep13</command> to get to the terminal server.</para> - </sect2> - - <sect2> - <title>Can Tip Try More Than One Line for Each Site?</title> - - <para>This is often a problem where a university has several modem lines - and several thousand students trying to use them.</para> - - <para>Make an entry for your university in - <filename>/etc/remote</filename> and use <literal>@</literal> for the - <literal>pn</literal> capability:</para> - - <programlisting>big-university:\ - :pn=\@:tc=dialout -dialout:\ - :dv=/dev/cuad3:br#9600:at=courier:du:pa=none:</programlisting> - - <para>Then, list the phone numbers for the university in - <filename>/etc/phones</filename>:</para> - - <programlisting>big-university 5551111 -big-university 5551112 -big-university 5551113 -big-university 5551114</programlisting> - - <para><command>tip</command> will try each one in the listed order, then - give up. If you want to keep retrying, run <command>tip</command> in - a while loop.</para> - </sect2> - - <sect2> - <title>Why Do I Have to Hit - <keycombo action="simul"> - <keycap>Ctrl</keycap> - <keycap>P</keycap> - </keycombo> - Twice to Send - <keycombo action="simul"> - <keycap>Ctrl</keycap> - <keycap>P</keycap> - </keycombo> - Once?</title> - - <para><keycombo action="simul"><keycap>Ctrl</keycap><keycap>P</keycap></keycombo> is the default <quote>force</quote> character, used to tell - <command>tip</command> that the next character is literal data. You - can set the force character to any other character with the - <command>~s</command> escape, which means <quote>set a - variable.</quote></para> - - <para>Type - <command>~sforce=single-char</command> - followed by a newline. <replaceable>single-char</replaceable> is any - single character. If you leave out - <replaceable>single-char</replaceable>, then the force character is - the nul character, which you can get by typing - <keycombo action="simul"> - <keycap>Ctrl</keycap><keycap>2</keycap> - </keycombo> - or - <keycombo action="simul"> - <keycap>Ctrl</keycap><keycap>Space</keycap> - </keycombo>. - A pretty good value for <replaceable>single-char</replaceable> is - <keycombo action="simul"> - <keycap>Shift</keycap> - <keycap>Ctrl</keycap> - <keycap>6</keycap> - </keycombo>, which is only used on some terminal - servers.</para> - - <para>You can have the force character be whatever you want by - specifying the following in your <filename>$HOME/.tiprc</filename> - file:</para> - - <programlisting>force=<single-char></programlisting> - </sect2> - - <sect2> - <title>Suddenly Everything I Type Is in Upper Case??</title> - - <para>You must have pressed - <keycombo action="simul"> - <keycap>Ctrl</keycap> - <keycap>A</keycap> - </keycombo>, <command>tip</command>'s - <quote>raise character,</quote> specially designed for people with - broken caps-lock keys. Use <command>~s</command> as above and set the - variable <literal>raisechar</literal> to something reasonable. In - fact, you can set it to the same as the force character, if you never - expect to use either of these features.</para> - - <para>Here is a sample .tiprc file perfect for - <application>Emacs</application> users who need to type - <keycombo action="simul"> - <keycap>Ctrl</keycap><keycap>2</keycap> - </keycombo> - and - <keycombo action="simul"> - <keycap>Ctrl</keycap><keycap>A</keycap> - </keycombo> - a lot:</para> - - <programlisting>force=^^ -raisechar=^^</programlisting> - - <para>The ^^ is - <keycombo action="simul"> - <keycap>Shift</keycap><keycap>Ctrl</keycap><keycap>6</keycap> - </keycombo>.</para> - - </sect2> - - <sect2> - <title>How Can I Do File Transfers with <command>tip</command>?</title> - - <para>If you are talking to another &unix; system, you can send and - receive files with <command>~p</command> (put) and - <command>~t</command> (take). These commands run - <command>cat</command> and <command>echo</command> on the remote - system to accept and send files. The syntax is:</para> - - <cmdsynopsis> - <command>~p</command> - <arg choice="plain">local-file</arg> - <arg choice="opt">remote-file</arg> - </cmdsynopsis> - - <cmdsynopsis> - <command>~t</command> - <arg choice="plain">remote-file</arg> - <arg choice="opt">local-file</arg> - </cmdsynopsis> - - <para>There is no error checking, so you probably should use another - protocol, like zmodem.</para> - </sect2> - - <sect2> - <title>How Can I Run zmodem with <command>tip</command>?</title> - - <para>To receive files, start the sending program on the remote end. - Then, type <command>~C rz</command> to begin receiving them - locally.</para> - - <para>To send files, start the receiving program on the remote end. - Then, type <command>~C sz files</command> - to send them to the remote system.</para> - </sect2> - </sect1> - - <sect1 xml:id="serialconsole-setup"> - <info><title>Setting Up the Serial Console</title> - <authorgroup> - <author><personname><firstname>Kazutaka</firstname><surname>YOKOTA</surname></personname><contrib>Contributed by </contrib></author> - </authorgroup> - <authorgroup> - <author><personname><firstname>Bill</firstname><surname>Paul</surname></personname><contrib>Based on a document by </contrib></author> - </authorgroup> - </info> - - <indexterm><primary>serial console</primary></indexterm> - - <sect2 xml:id="serialconsole-intro"> - <title>Introduction</title> - - <para>FreeBSD has the ability to boot on a system with only - a dumb terminal on a serial port as a console. Such a configuration - should be useful for two classes of people: system administrators who - wish to install FreeBSD on machines that have no keyboard or monitor - attached, and developers who want to debug the kernel or device - drivers.</para> - - <para>As described in <xref linkend="boot"/>, FreeBSD employs a three stage - bootstrap. The first two stages are in the boot block code which is - stored at the beginning of the FreeBSD slice on the boot disk. The - boot block will then load and run the boot loader - (<filename>/boot/loader</filename>) as the third stage code.</para> - - <para>In order to set up the serial console you must configure the boot - block code, the boot loader code and the kernel.</para> - - </sect2> - - <sect2 xml:id="serialconsole-howto-fast"> - <title>Serial Console Configuration, Terse Version</title> - - <para>This section assumes that you are using the default setup - and just want a fast overview of setting up the serial - console.</para> - - <procedure> - - <step> - <para>Connect the serial cable to COM1 and the controlling - terminal.</para> - </step> - - <step> - <para>To see all boot messages on the serial console, issue - the following command while logged in as the superuser:</para> - <screen>&prompt.root; echo 'console="comconsole"' >> /boot/loader.conf</screen> - </step> - - <step> - <para>Edit <filename>/etc/ttys</filename> and change - <literal>off</literal> to <literal>on</literal> and - <literal>dialup</literal> to <literal>vt100</literal> for the - <literal>ttyd0</literal> entry. Otherwise a password will not be - required to connect via the serial console, resulting in a - potential security hole.</para> - </step> - - <step> - <para>Reboot the system to see if the changes took effect.</para> - </step> - - </procedure> - - <para>If a different configuration is required, a more in depth - configuration explanation exists in - <xref linkend="serialconsole-howto"/>.</para> - </sect2> - - <sect2 xml:id="serialconsole-howto"> - <title>Serial Console Configuration</title> - - <procedure> - <step> - <para>Prepare a serial cable.</para> - - <indexterm><primary>null-modem cable</primary></indexterm> - <para>You will need either a null-modem cable or a standard serial - cable and a null-modem adapter. See <xref linkend="serial-cables-ports"/> for - a discussion on serial cables.</para> - </step> - - <step> - <para>Unplug your keyboard.</para> - - <para>Most PC systems probe for the keyboard during the Power-On - Self-Test (POST) and will generate an error if the keyboard is not - detected. Some machines complain loudly about the lack of a - keyboard and will not continue to boot until it is plugged - in.</para> - - <para>If your computer complains about the error, but boots anyway, - then you do not have to do anything special. (Some machines with - Phoenix BIOS installed merely say <errorname>Keyboard - failed</errorname> and continue to boot normally.)</para> - - <para>If your computer refuses to boot without a keyboard attached - then you will have to configure the BIOS so that it ignores this - error (if it can). Consult your motherboard's manual for details - on how to do this.</para> - - <tip> - <para>Set the keyboard to <quote>Not installed</quote> in the - BIOS setup. You will still - be able to use your keyboard. All this does is tell the BIOS - not to probe for a keyboard at power-on. Your BIOS should not - complain if the keyboard is absent. You can leave the - keyboard plugged in even with this flag set to <quote>Not - installed</quote> and the keyboard will still work.</para> - </tip> - - <note> - <para>If your system has a &ps2; mouse, chances are very good that - you may have to unplug your mouse as well as your keyboard. - This is because &ps2; mice share some hardware with the keyboard - and leaving the mouse plugged in can fool the keyboard probe - into thinking the keyboard is still there. It is said that a - Gateway 2000 Pentium 90 MHz system with an AMI BIOS that behaves - this way. In general, this is not a problem since the mouse is - not much good without the keyboard anyway.</para> - </note> - </step> - - <step> - <para>Plug a dumb terminal into <filename>COM1</filename> - (<filename>sio0</filename>).</para> - - <para>If you do not have a dumb terminal, you can use an old PC/XT - with a modem program, or the serial port on another &unix; box. If - you do not have a <filename>COM1</filename> - (<filename>sio0</filename>), get one. At this time, there is - no way to select a port other than <filename>COM1</filename> - for the boot blocks without recompiling the boot blocks. If you - are already using <filename>COM1</filename> for another - device, you will have to temporarily remove that device and - install a new boot block and kernel once you get FreeBSD up and - running. (It is assumed that <filename>COM1</filename> will - be available on a file/compute/terminal server anyway; if you - really need <filename>COM1</filename> for something else - (and you cannot switch that something else to - <filename>COM2</filename> (<filename>sio1</filename>)), - then you probably should not even be bothering with all this in - the first place.)</para> - </step> - - <step> - <para>Make sure the configuration file of your kernel has - appropriate flags set for <filename>COM1</filename> - (<filename>sio0</filename>).</para> - - <para>Relevant flags are:</para> - - <variablelist> - <varlistentry> - <term><literal>0x10</literal></term> - - <listitem> - <para>Enables console support for this unit. The other - console flags are ignored unless this is set. Currently, at - most one unit can have console support; the first one (in - config file order) with this flag set is preferred. This - option alone will not make the serial port the console. Set - the following flag or use the <option>-h</option> option - described below, together with this flag.</para> - </listitem> - </varlistentry> - - <varlistentry> - <term><literal>0x20</literal></term> - - <listitem> - <para>Forces this unit to be the console (unless there is - another higher priority console), regardless of the - <option>-h</option> option discussed below. - The flag <literal>0x20</literal> must be used - together with the <option>0x10</option> flag.</para> - </listitem> - </varlistentry> - - <varlistentry> - <term><literal>0x40</literal></term> - - <listitem> - <para>Reserves this unit (in conjunction with - <literal>0x10</literal>) and makes the unit - unavailable for normal access. You should not set - this flag to the serial port unit which you want to - use as the serial console. The only use of this - flag is to designate the unit for kernel remote - debugging. See <link xlink:href="&url.books.developers-handbook;/index.html">The - Developer's Handbook</link> for more information on - remote debugging.</para> - - <note> - <para>In FreeBSD 4.0 or later the semantics of the - flag <literal>0x40</literal> are slightly different and - there is another flag to specify a serial port for remote - debugging.</para> - </note> - </listitem> - </varlistentry> - </variablelist> - - <para>Example:</para> - - <programlisting>device sio0 at isa? port IO_COM1 flags 0x10 irq 4</programlisting> - - <para>See the &man.sio.4; manual page for more details.</para> - - <para>If the flags were not set, you need to run UserConfig (on a - different console) or recompile the kernel.</para> - </step> - - <step> - <para>Create <filename>boot.config</filename> in the root directory - of the <literal>a</literal> partition on the boot drive.</para> - - <para>This file will instruct the boot block code how you would like - to boot the system. In order to activate the serial console, you - need one or more of the following options—if you want - multiple options, include them all on the same line:</para> - - <variablelist> - <varlistentry> - <term><option>-h</option></term> - - <listitem> - <para>Toggles internal and serial consoles. You can use this - to switch console devices. For instance, if you boot from - the internal (video) console, you can use - <option>-h</option> to direct the boot loader and the kernel - to use the serial port as its console device. Alternatively, - if you boot from the serial port, you can use the - <option>-h</option> to tell the boot loader and the kernel - to use the video display as the console instead.</para> - </listitem> - </varlistentry> - - <varlistentry> - <term><option>-D</option></term> - - <listitem> - <para>Toggles single and dual console configurations. In the - single configuration the console will be either the internal - console (video display) or the serial port, depending on the - state of the <option>-h</option> option above. In the dual - console configuration, both the video display and the - serial port will become the console at the same time, - regardless of the state of the <option>-h</option> option. - However, note that the dual console configuration takes effect - only during the boot block is running. Once the boot loader - gets control, the console specified by the - <option>-h</option> option becomes the only console.</para> - </listitem> - </varlistentry> - - <varlistentry> - <term><option>-P</option></term> - - <listitem> - <para>Makes the boot block probe the keyboard. If no keyboard - is found, the <option>-D</option> and <option>-h</option> - options are automatically set.</para> - - <note> - <para>Due to space constraints in the current version of the - boot blocks, the <option>-P</option> option is capable of - detecting extended keyboards only. Keyboards with less - than 101 keys (and without F11 and F12 keys) may not be - detected. Keyboards on some laptop computers may not be - properly found because of this limitation. If this is - the case with your system, you have to abandon using - the <option>-P</option> option. Unfortunately there is no - workaround for this problem.</para> - </note> - </listitem> - </varlistentry> - </variablelist> - - <para>Use either the <option>-P</option> option to select the - console automatically, or the <option>-h</option> option to - activate the serial console.</para> - - <para>You may include other options described in &man.boot.8; as - well.</para> - - <para>The options, except for <option>-P</option>, will be passed to - the boot loader (<filename>/boot/loader</filename>). The boot - loader will determine which of the internal video or the serial - port should become the console by examining the state of the - <option>-h</option> option alone. This means that if you specify - the <option>-D</option> option but not the <option>-h</option> - option in <filename>/boot.config</filename>, you can use the - serial port as the console only during the boot block; the boot - loader will use the internal video display as the console.</para> - </step> - - <step> - <para>Boot the machine.</para> - - <para>When you start your FreeBSD box, the boot blocks will echo the - contents of <filename>/boot.config</filename> to the console. For - example:</para> - - <screen>/boot.config: -P -Keyboard: no</screen> - - <para>The second line appears only if you put <option>-P</option> in - <filename>/boot.config</filename> and indicates presence/absence - of the keyboard. These messages go to either serial or internal - console, or both, depending on the option in - <filename>/boot.config</filename>.</para> - - <informaltable frame="none" pgwide="1"> - <tgroup cols="2"> - <thead> - <row> - <entry align="left">Options</entry> - <entry align="left">Message goes to</entry> - </row> - </thead> - - <tbody> - <row> - <entry>none</entry> - <entry>internal console</entry> - </row> - - <row> - <entry><option>-h</option></entry> - <entry>serial console</entry> - </row> - - <row> - <entry><option>-D</option></entry> - <entry>serial and internal consoles</entry> - </row> - - <row> - <entry><option>-Dh</option></entry> - <entry>serial and internal consoles</entry> - </row> - - <row> - <entry><option>-P</option>, keyboard present</entry> - <entry>internal console</entry> - </row> - - <row> - <entry><option>-P</option>, keyboard absent</entry> - <entry>serial console</entry> - </row> - </tbody> - </tgroup> - </informaltable> - - <para>After the above messages, there will be a small pause before - the boot blocks continue loading the boot loader and before any - further messages printed to the console. Under normal - circumstances, you do not need to interrupt the boot blocks, but - you may want to do so in order to make sure things are set up - correctly.</para> - - <para>Hit any key, other than <keycode>Enter</keycode>, at the console to - interrupt the boot process. The boot blocks will then prompt you - for further action. You should now see something like:</para> - - <screen>>> FreeBSD/i386 BOOT -Default: 0:ad(0,a)/boot/loader -boot:</screen> - - <para>Verify the above message appears on either the serial or - internal console or both, according to the options you put in - <filename>/boot.config</filename>. If the message appears in the - correct console, hit <keycode>Enter</keycode> to continue the boot - process.</para> - - <para>If you want the serial console but you do not see the prompt - on the serial terminal, something is wrong with your settings. In - the meantime, you enter <option>-h</option> and hit Enter/Return - (if possible) to tell the boot block (and then the boot loader and - the kernel) to choose the serial port for the console. Once the - system is up, go back and check what went wrong.</para> - </step> - </procedure> - - <para>After the boot loader is loaded and you are in the third stage of - the boot process you can still switch between the internal console and - the serial console by setting appropriate environment variables in the - boot loader. See <xref linkend="serialconsole-loader"/>.</para> - </sect2> - - <sect2 xml:id="serialconsole-summary"> - <title>Summary</title> - - <para>Here is the summary of various settings discussed in this section - and the console eventually selected.</para> - - <sect3> - <title>Case 1: You Set the Flags to 0x10 for - <filename>sio0</filename></title> - - <programlisting>device sio0 at isa? port IO_COM1 flags 0x10 irq 4</programlisting> - - <informaltable frame="none" pgwide="1"> - <tgroup cols="4"> - <thead> - <row> - <entry align="left">Options in /boot.config</entry> - <entry align="left">Console during boot blocks</entry> - <entry align="left">Console during boot loader</entry> - <entry align="left">Console in kernel</entry> - </row> - </thead> - - <tbody> - <row> - <entry>nothing</entry> - <entry>internal</entry> - <entry>internal</entry> - <entry>internal</entry> - </row> - - <row> - <entry><option>-h</option></entry> - <entry>serial</entry> - <entry>serial</entry> - <entry>serial</entry> - </row> - - <row> - <entry><option>-D</option></entry> - <entry>serial and internal</entry> - <entry>internal</entry> - <entry>internal</entry> - </row> - - <row> - <entry><option>-Dh</option></entry> - <entry>serial and internal</entry> - <entry>serial</entry> - <entry>serial</entry> - </row> - - <row> - <entry><option>-P</option>, keyboard present</entry> - <entry>internal</entry> - <entry>internal</entry> - <entry>internal</entry> - </row> - - <row> - <entry><option>-P</option>, keyboard absent</entry> - <entry>serial and internal</entry> - <entry>serial</entry> - <entry>serial</entry> - </row> - </tbody> - </tgroup> - </informaltable> - </sect3> - - <sect3> - <title>Case 2: You Set the Flags to 0x30 for sio0</title> - - <programlisting>device sio0 at isa? port IO_COM1 flags 0x30 irq 4</programlisting> - - <informaltable frame="none" pgwide="1"> - <tgroup cols="4"> - <thead> - <row> - <entry align="left">Options in /boot.config</entry> - <entry align="left">Console during boot blocks</entry> - <entry align="left">Console during boot loader</entry> - <entry align="left">Console in kernel</entry> - </row> - </thead> - - <tbody> - <row> - <entry>nothing</entry> - <entry>internal</entry> - <entry>internal</entry> - <entry>serial</entry> - </row> - - <row> - <entry><option>-h</option></entry> - <entry>serial</entry> - <entry>serial</entry> - <entry>serial</entry> - </row> - - <row> - <entry><option>-D</option></entry> - <entry>serial and internal</entry> - <entry>internal</entry> - <entry>serial</entry> - </row> - - <row> - <entry><option>-Dh</option></entry> - <entry>serial and internal</entry> - <entry>serial</entry> - <entry>serial</entry> - </row> - - <row> - <entry><option>-P</option>, keyboard present</entry> - <entry>internal</entry> - <entry>internal</entry> - <entry>serial</entry> - </row> - - <row> - <entry><option>-P</option>, keyboard absent</entry> - <entry>serial and internal</entry> - <entry>serial</entry> - <entry>serial</entry> - </row> - </tbody> - </tgroup> - </informaltable> - </sect3> - </sect2> - - <sect2 xml:id="serialconsole-tips"> - <title>Tips for the Serial Console</title> - - <sect3> - <title>Setting a Faster Serial Port Speed</title> - - <para>By default, the serial port settings are: 9600 baud, 8 - bits, no parity, and 1 stop bit. If you wish to change the speed, you - need to recompile at least the boot blocks. Add the following line - to <filename>/etc/make.conf</filename> and compile new boot - blocks:</para> - - <programlisting>BOOT_COMCONSOLE_SPEED=19200</programlisting> - - <para>See <xref linkend="serialconsole-com2"/> for detailed - instructions about building and installing new boot blocks.</para> - - <para>If the serial console is configured in some other way than by - booting with <option>-h</option>, or if the serial console used by - the kernel is different from the one used by the boot blocks, then - you must also add the following option to the kernel configuration - file and compile a new kernel:</para> - - <programlisting>options CONSPEED=19200</programlisting> - </sect3> - - <sect3 xml:id="serialconsole-com2"> - <title>Using Serial Port Other Than <filename>sio0</filename> for - the Console</title> - - <para>Using a port other than <filename>sio0</filename> as the - console requires some recompiling. If you want to use another - serial port for whatever reasons, recompile the boot blocks, the - boot loader and the kernel as follows.</para> - - <procedure> - <step> - <para>Get the kernel source.</para> - </step> - - <step> - <para>Edit <filename>/etc/make.conf</filename> and set - <literal>BOOT_COMCONSOLE_PORT</literal> to the address of the - port you want to use (0x3F8, 0x2F8, 0x3E8 or 0x2E8). Only - <filename>sio0</filename> through - <filename>sio3</filename> (<filename>COM1</filename> - through <filename>COM4</filename>) can be used; multiport - serial cards will not work. No interrupt setting is - needed.</para> - </step> - - <step> - <para>Create a custom kernel configuration file and add - appropriate flags for the serial port you want to use. For - example, if you want to make <filename>sio1</filename> - (<filename>COM2</filename>) the console:</para> - - <programlisting>device sio1 at isa? port IO_COM2 flags 0x10 irq 3</programlisting> - - <para>or</para> - - <programlisting>device sio1 at isa? port IO_COM2 flags 0x30 irq 3</programlisting> - - <para>The console flags for the other serial ports should not be - set.</para> - </step> - - <step> - <para>Recompile and install the boot blocks and the boot loader:</para> - - <screen>&prompt.root; <userinput>cd /sys/boot</userinput> -&prompt.root; <userinput>make clean</userinput> -&prompt.root; <userinput>make</userinput> -&prompt.root; <userinput>make install</userinput></screen> - </step> - - <step> - <para>Rebuild and install the kernel.</para> - </step> - - <step> - <para>Write the boot blocks to the boot disk with - &man.disklabel.8; and boot from the new kernel.</para> - </step> - </procedure> - </sect3> - - <sect3 xml:id="serialconsole-ddb"> - <title>Entering the DDB Debugger from the Serial Line</title> - - <para>If you wish to drop into the kernel debugger from the serial - console (useful for remote diagnostics, but also dangerous if you - generate a spurious BREAK on the serial port!) then you should - compile your kernel with the following options:</para> - - <programlisting>options BREAK_TO_DEBUGGER -options DDB</programlisting> - </sect3> - - <sect3> - <title>Getting a Login Prompt on the Serial Console</title> - - <para>While this is not required, you may wish to get a - <emphasis>login</emphasis> prompt over the serial line, now that you - can see boot messages and can enter the kernel debugging session - through the serial console. Here is how to do it.</para> - - <para>Open the file <filename>/etc/ttys</filename> with an editor - and locate the lines:</para> - - <programlisting>ttyd0 "/usr/libexec/getty std.9600" unknown off secure -ttyd1 "/usr/libexec/getty std.9600" unknown off secure -ttyd2 "/usr/libexec/getty std.9600" unknown off secure -ttyd3 "/usr/libexec/getty std.9600" unknown off secure</programlisting> - - <para><literal>ttyd0</literal> through <literal>ttyd3</literal> - corresponds to <filename>COM1</filename> through - <filename>COM4</filename>. Change <literal>off</literal> to - <literal>on</literal> for the desired port. If you have changed the - speed of the serial port, you need to change - <literal>std.9600</literal> to match the current setting, e.g. - <literal>std.19200</literal>.</para> - - <para>You may also want to change the terminal type from - <literal>unknown</literal> to the actual type of your serial - terminal.</para> - - <para>After editing the file, you must <command>kill -HUP 1</command> - to make this change take effect.</para> - </sect3> - </sect2> - - <sect2 xml:id="serialconsole-loader"> - <title>Changing Console from the Boot Loader</title> - - <para>Previous sections described how to set up the serial console by - tweaking the boot block. This section shows that you can specify the - console by entering some commands and environment variables in the - boot loader. As the boot loader is invoked at the third stage of the - boot process, after the boot block, the settings in the boot loader - will override the settings in the boot block.</para> - - <sect3> - <title>Setting Up the Serial Console</title> - - <para>You can easily specify the boot loader and the kernel to use the - serial console by writing just one line in - <filename>/boot/loader.rc</filename>:</para> - - <programlisting>set console="comconsole"</programlisting> - - <para>This will take effect regardless of the settings in the boot - block discussed in the previous section.</para> - - <para>You had better put the above line as the first line of - <filename>/boot/loader.rc</filename> so as to see boot messages on - the serial console as early as possible.</para> - - <para>Likewise, you can specify the internal console as:</para> - - <programlisting>set console="vidconsole"</programlisting> - - <para>If you do not set the boot loader environment variable - <envar>console</envar>, the boot loader, and subsequently the - kernel, will use whichever console indicated by the - <option>-h</option> option in the boot block.</para> - - <para>In versions 3.2 or later, you may specify the console in - <filename>/boot/loader.conf.local</filename> or - <filename>/boot/loader.conf</filename>, rather than in - <filename>/boot/loader.rc</filename>. In this method your - <filename>/boot/loader.rc</filename> should look like:</para> - - <programlisting>include /boot/loader.4th -start</programlisting> - - <para>Then, create <filename>/boot/loader.conf.local</filename> and - put the following line there.</para> - - <programlisting>console=comconsole</programlisting> - - <para>or</para> - - <programlisting>console=vidconsole</programlisting> - - <para>See &man.loader.conf.5; for more information.</para> - - <note> - <para>At the moment, the boot loader has no option equivalent to the - <option>-P</option> option in the boot block, and there is no - provision to automatically select the internal console and the - serial console based on the presence of the keyboard.</para> - </note> - </sect3> - - <sect3> - <title>Using a Serial Port Other Than <filename>sio0</filename> for - the Console</title> - - <para>You need to recompile the boot loader to use a serial port other - than <filename>sio0</filename> for the serial console. Follow the - procedure described in <xref linkend="serialconsole-com2"/>.</para> - </sect3> - </sect2> - - <sect2 xml:id="serialconsole-caveats"> - <title>Caveats</title> - - <para>The idea here is to allow people to set up dedicated servers that - require no graphics hardware or attached keyboards. Unfortunately, - while most systems will let you boot without a keyboard, there - are quite a few that will not let you boot without a graphics adapter. - Machines with AMI BIOSes can be configured to boot with no graphics - adapter installed simply by changing the <quote>graphics adapter</quote> setting in - the CMOS configuration to <quote>Not installed.</quote></para> - - <para>However, many machines do not support this option and will refuse - to boot if you have no display hardware in the system. With these - machines, you will have to leave some kind of graphics card plugged in, - (even if it is just a junky mono board) although you will not have to - attach a monitor. You might also try installing an AMI - BIOS.</para> - </sect2> - </sect1> -</chapter> |