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diff --git a/en_US.ISO8859-1/articles/solid-state/article.sgml b/en_US.ISO8859-1/articles/solid-state/article.sgml deleted file mode 100644 index cff6136296..0000000000 --- a/en_US.ISO8859-1/articles/solid-state/article.sgml +++ /dev/null @@ -1,635 +0,0 @@ -<!-- Copyright (c) 2001 The FreeBSD Documentation Project - - Redistribution and use in source (SGML DocBook) and 'compiled' forms - (SGML, HTML, PDF, PostScript, RTF and so forth) with or without - modification, are permitted provided that the following conditions - are met: - - 1. Redistributions of source code (SGML DocBook) must retain the above - copyright notice, this list of conditions and the following - disclaimer as the first lines of this file unmodified. - - 2. Redistributions in compiled form (transformed to other DTDs, - converted to PDF, PostScript, RTF and other formats) must reproduce - the above copyright notice, this list of conditions and the - following disclaimer in the documentation and/or other materials - provided with the distribution. - - THIS DOCUMENTATION IS PROVIDED BY THE FREEBSD DOCUMENTATION PROJECT "AS - IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, - THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR - PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL NIK CLAYTON BE LIABLE FOR ANY - DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, - STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN - ANY WAY OUT OF THE USE OF THIS DOCUMENTATION, EVEN IF ADVISED OF THE - POSSIBILITY OF SUCH DAMAGE. - - $FreeBSD$ ---> - -<!DOCTYPE article PUBLIC "-//FreeBSD//DTD DocBook V4.1-Based Extension//EN" [ -<!ENTITY % articles.ent PUBLIC "-//FreeBSD//ENTITIES DocBook FreeBSD Articles Entity Set//EN"> -%articles.ent; -<!ENTITY legalnotice SYSTEM "../../share/sgml/legalnotice.sgml"> -]> - -<article> - <articleinfo> - <title>FreeBSD and Solid State Devices</title> - - <authorgroup> - <author> - <firstname>John</firstname> - <surname>Kozubik</surname> - - <affiliation> - <address><email>john@kozubik.com</email></address> - </affiliation> - </author> - </authorgroup> - - <pubdate>$FreeBSD$</pubdate> - - <copyright> - <year>2001</year> - <holder>The FreeBSD Documentation Project</holder> - </copyright> - - <legalnotice id="trademarks" role="trademarks"> - &tm-attrib.freebsd; - &tm-attrib.m-systems; - &tm-attrib.general; - </legalnotice> - - &legalnotice; - - <abstract> - <para>This article covers the use of solid state disk devices in FreeBSD - to create embedded systems.</para> - - <para>Embedded systems have the advantage of increased stability due to - the lack of integral moving parts (hard drives). Account must be - taken, however, for the generally low disk space available in the - system and the durability of the storage medium.</para> - - <para>Specific topics to be covered include the types and attributes of - solid state media suitable for disk use in FreeBSD, kernel options - that are of interest in such an environment, the - <filename>rc.diskless</filename> mechanisms that automate the - initialization of such systems and the need for read-only filesystems, - and building filesystems from scratch. The article will conclude - with some general strategies for small and read-only FreeBSD - environments.</para> - </abstract> - </articleinfo> - - <sect1 id="intro"> - <title>Solid State Disk Devices</title> - - <para>The scope of this article will be limited to solid state disk - devices made from flash memory. Flash memory is a solid state memory - (no moving parts) that is non-volatile (the memory maintains data even - after all power sources have been disconnected). Flash memory can - withstand tremendous physical shock and is reasonably fast (the flash - memory solutions covered in this article are slightly slower than a EIDE - hard disk for write operations, and much faster for read operations). - One very important aspect of flash memory, the ramifications of which - will be discussed later in this article, is that each sector has a - limited rewrite capacity. You can only write, erase, and write again to - a sector of flash memory a certain number of times before the sector - becomes permanently unusable. Although many flash memory products - automatically map bad blocks, and although some even distribute write - operations evenly throughout the unit, the fact remains that there - exists a limit to the amount of writing that can be done to the device. - Competitive units have between 1,000,000 and 10,000,000 writes per - sector in their specification. This figure varies due to the - temperature of the environment.</para> - - <para>Specifically, we will be discussing ATA compatible compact-flash - units and the M-Systems &diskonchip; flash memory unit. ATA compatible - compact-flash cards are quite popular as storage media for digital - cameras. Of particular interest is the fact that they pin out directly - to the IDE bus and are compatible with the ATA command set. Therefore, - with a very simple and low-cost adaptor, these devices can be attached - directly to an IDE bus in a computer. Once implemented in this manner, - operating systems such as FreeBSD see the device as a normal hard disk - (albeit small). The M-Systems &diskonchip; product is based on the same - underlying flash memory technology as ATA compatible compact-flash - cards, but resides in a DIP form factor and is not ATA compatible. To - use such a device, not only must you install it on a motherboard that - has a &diskonchip; socket, you must also build the `fla` driver into any - FreeBSD kernel you wish to use it with. Further, there is critical, - manufacturer-specific data residing in the boot sector of this device, - so you must take care not to install the FreeBSD (or any other) boot - loader when using this.</para> - - <para>Other solid state disk solutions do exist, but their expense, - obscurity, and relative unease of use places them beyond the scope of - this article.</para> - </sect1> - - <sect1 id="kernel"> - <title>Kernel Options</title> - - <para>A few kernel options are of specific interest to those creating - an embedded FreeBSD system.</para> - - <para>First, all embedded FreeBSD systems that use flash memory as system - disk will be interested in memory disks and memory filesystems. Because - of the limited number of writes that can be done to flash memory, the - disk and the filesystems on the disk will most likely be mounted - read-only. In this environment, filesystems such as - <filename>/tmp</filename> and <filename>/var</filename> are mounted as - memory filesystems to allow the system to create logs and update - counters and temporary files. Memory filesystems are a critical - component to a successful solid state FreeBSD implementation.</para> - - <para>You should make sure the following lines exist in your kernel - configuration file:</para> - - <programlisting>options MFS # Memory Filesystem -options MD_ROOT # md device usable as a potential root device -pseudo-device md # memory disk</programlisting> - - <para>Second, if you will be using the M-Systems &diskonchip; product, you - must also include this line:</para> - - <programlisting>device fla0 at isa?</programlisting> - </sect1> - - <sect1 id="ro-fs"> - <title><filename>rc.diskless</filename> and Read-Only Filesystems</title> - - <para>The post-boot initialization of an embedded FreeBSD system is - controlled by <filename>/etc/rc.diskless2</filename> - (<filename>/etc/rc.diskless1</filename> is for BOOTP diskless boot). - This initialization script is invoked by placing a line in - <filename>/etc/rc.conf</filename> as follows:</para> - - <programlisting>diskless_mount=/etc/rc.diskless2</programlisting> - - <para><filename>rc.diskless2</filename> mounts <filename>/var</filename> - as a memory filesystem, makes a configurable list of directories in - <filename>/var</filename> with the &man.mkdir.1; command, changes modes - on some of those directories, and extracts a list of device entries to - copy to a writable (again, a memory filesystem) - <filename>/dev</filename> partition. In the execution of - <filename>/etc/rc.diskless2</filename>, one other - <filename>rc.conf</filename> variable comes into play - - <literal>varsize</literal>. The <filename>/etc/rc.diskless2</filename> - file creates a <filename>/var</filename> partition based on the value of - this variable in <filename>rc.conf</filename>:</para> - - <programlisting>varsize=8192</programlisting> - - <para>Remember that this value is in sectors. The creation of the - <filename>/dev</filename> partition by - <filename>/etc/rc.diskless2</filename>, however, is governed by a - hard-coded value of 4096 sectors. It is trivial to change this entry in - the <filename>/etc/rc.diskless2</filename> file itself, although you - should not need more space than that for - <filename>/dev</filename>.</para> - - <para>It is important to remember that the - <filename>/etc/rc.diskless2</filename> script assumes that you have - already removed your conventional <filename>/tmp</filename> partition - and replaced it with a symbolic link to <filename>/var/tmp</filename>. - Because <filename>tmp</filename> is one of the directories created in - <filename>/var</filename> by the <filename>/etc/rc.diskless2</filename> - script, and because <filename>/var</filename> is a memory filesystem - (which is mounted read-write), <filename>/tmp</filename> will now be a - directory that is read-write as well.</para> - - <para>The fact that <filename>/var</filename> and - <filename>/dev</filename> are read-write filesystems is an important - distinction, as the <filename>/</filename> partition (and any other - partitions you may have on your flash media) should be mounted - read-only. Remember that in <xref linkend="intro"> we detailed the - limitations of flash memory - specifically the limited write capability. - The importance of not mounting filesystems on flash media read-write, - and the importance of not using a swap file, cannot be overstated. A - swap file on a busy system can burn through a piece of flash media in - less than one year. Heavy logging or temporary file creation and - destruction can do the same. Therefore, in addition to removing the - <literal>swap</literal> and <literal>/proc</literal> entries from your - <filename>/etc/fstab</filename> file, you should also change the Options - field for each filesystem to <literal>ro</literal> as follows:</para> - - <programlisting># Device Mountpoint FStype Options Dump Pass# -/dev/ad0s1a / ufs ro 1 1</programlisting> - - <para>A few applications in the average system will immediately begin to - fail as a result of this change. For instance, ports will not install - from the ports tree because the - <filename>/var/db/port.mkversion</filename> file does not exist. cron - will not run properly as a result of missing cron tabs in the - <filename>/var</filename> created by - <filename>/etc/rc.diskless2</filename>, and syslog and dhcp will - encounter problems as well as a result of the read-only filesystem and - missing items in the <filename>/var</filename> that - <filename>/etc/rc.diskless2</filename> has created. These are only - temporary problems though, and are addressed, along with solutions to - the execution of other common software packages in - <xref linkend="strategies">.</para> - - <para>An important thing to remember is that a filesystem that was mounted - read-only with <filename>/etc/fstab</filename> can be made read-write at - any time by issuing the command:</para> - - <screen>&prompt.root; <userinput>/sbin/mount -uw <replaceable>partition</replaceable></userinput></screen> - - <para>and can be toggled back to read-only with the command:</para> - - <screen>&prompt.root; <userinput>/sbin/mount -ur <replaceable>partition</replaceable></userinput></screen> - </sect1> - - <sect1> - <title>Building a File System From Scratch</title> - - <para>Because ATA compatible compact-flash cards are seen by FreeBSD as - normal IDE hard drives, as is a M-Systems &diskonchip; product (when you - are running a kernel with the fla driver built in) you could - theoretically install FreeBSD from the network using the kern and - mfsroot floppies or from a CD. Other than the fact that you should not - write a boot-loader of any kind to the M-Systems device, no special - instructions are needed.</para> - - <para>However, even a small installation of FreeBSD using normal - installation procedures can produce a system in size of greater than 200 - megabytes. Because most people will be using smaller flash memory - devices (128 megabytes is considered fairly large - 32 or even 16 - megabytes is common) an installation using normal mechanisms is not - possible—there is simply not enough disk space for even the - smallest of conventional installations.</para> - - <para>The easiest way to overcome this space limitation is to install - FreeBSD using conventional means to a normal hard disk. After the - installation is complete, pare down the operating system to a size that - will fit onto your flash media, then tar the entire filesystem. The - following steps will guide you through the process of preparing a piece - of flash memory for your tarred filesystem. Remember, because a normal - installation is not being performed, operations such as partitioning, - labeling, file-system creation, etc. need to be performed by hand. In - addition to the kern and mfsroot floppy disks, you will also need to use - the fixit floppy. If you are using a M-Systems &diskonchip;, the kernel - on your kern floppy must have the <literal>fla</literal> option detailed - in <xref linkend="kernel"> compiled into it. Please see - <xref linkend="kern.flp"> for instructions on creating a new kernel for - <filename>kern.flp</filename>.</para> - - <procedure> - <step> - <title>Partitioning your flash media device</title> - - <para>After booting with the kern and mfsroot floppies, choose - <literal>custom</literal> from the installation menu. In the custom - installation menu, choose <literal>partition</literal>. In the - partition menu, you should delete all existing partitions using the - <keycap>d</keycap> key. After deleting all existing partitions, - create a partition using the <keycap>c</keycap> key and accept the - default value for the size of the partition. When asked for the - type of the partition, make sure the value is set to - <literal>165</literal>. Now write this partition table to the disk - by pressing the <keycap>w</keycap> key (this is a hidden option on - this screen). When presented with a menu to choose a boot manager, - take care to select <literal>None</literal> if you are using an - M-Systems &diskonchip;. If you are using an ATA compatible compact - flash card, you should choose the FreeBSD Boot Manager. Now press - the <keycap>q</keycap> key to quit the partition menu. You will be - shown the boot manager menu once more - repeat the choice you made - earlier.</para> - </step> - - <step> - <title>Creating filesystems on your flash memory device</title> - - <para>Exit the custom installation menu, and from the main - installation menu choose the <literal>fixit</literal> option. After - entering the fixit environment, enter the following commands:</para> - - <informaltable frame="none"> - <tgroup cols="2"> - <thead> - <row> - <entry align="center">ATA compatible</entry> - - <entry align="center">&diskonchip;</entry> - </row> - </thead> - <tbody> - <row> - <entry><para><screen>&prompt.root; <userinput>mknod /dev/ad0a c 116 0</userinput> -&prompt.root; <userinput>mknod /dev/ad0c c 116 2</userinput> -&prompt.root; <userinput>disklabel -e /dev/ad0c</userinput></screen></para></entry> - - <entry><para><screen>&prompt.root; <userinput>mknod /dev/fla0a c 102 0</userinput> -&prompt.root; <userinput>mknod /dev/fla0c c 102 2</userinput> -&prompt.root; <userinput>disklabel -e /dev/fla0c</userinput></screen></para></entry> - </row> - </tbody> - </tgroup> - </informaltable> - - <para>At this point you will have entered the vi editor under the - auspices of the disklabel command. If you are using &diskonchip;, - the first step will be to change the type value near the beginning - of the file from <literal>ESDI</literal> to - <literal>DOC2K</literal>. Next, regardless of whether you are using - &diskonchip; or ATA compatible compact flash media, you need to add - an <literal>a:</literal> line at the end of the file. This - <literal>a:</literal> line should look like:</para> - - <programlisting>a: <replaceable>123456</replaceable> 0 4.2BSD 0 0</programlisting> - - <para>Where <replaceable>123456</replaceable> is a number that is - exactly the same as the number in the existing <literal>c:</literal> - entry for size. Basically you are duplicating the existing - <literal>c:</literal> line as an <literal>a:</literal> line, making - sure that fstype is <literal>4.2BSD</literal>. Save the file and - exit.</para> - - <informaltable frame="none"> - <tgroup cols="2"> - <thead> - <row> - <entry align="center">ATA compatible</entry> - - <entry align="center">&diskonchip;</entry> - </row> - </thead> - <tbody> - <row> - <entry><para><screen>&prompt.root; <userinput>disklabel -B -r /dev/ad0c</userinput> -&prompt.root; <userinput>newfs /dev/ad0a</userinput></screen></para></entry> - - <entry><para><screen>&prompt.root; <userinput>disklabel -B -r /dev/fla0c</userinput> -&prompt.root; <userinput>newfs /dev/fla0a</userinput></screen></para></entry> - </row> - </tbody> - </tgroup> - </informaltable> - </step> - - <step> - <title>Placing your filesystem on the flash media</title> - - <para>Mount the newly prepared flash media:</para> - - <informaltable frame="none"> - <tgroup cols="2"> - <thead> - <row> - <entry align="center">ATA compatible</entry> - - <entry align="center">&diskonchip;</entry> - </row> - </thead> - <tbody> - <row> - <entry><para><screen>&prompt.root; <userinput>mount /dev/ad0a /flash</userinput></screen></para></entry> - - <entry><para><screen>&prompt.root; <userinput>mount /dev/fla0a /flash</userinput></screen></para></entry> - </row> - </tbody> - </tgroup> - </informaltable> - - <para>Bring this machine up on the network so we may transfer our tar - file and explode it onto our flash media filesystem. One example of - how to do this is:</para> - - <screen>&prompt.root; <userinput>ifconfig xl0 192.168.0.10 netmask 255.255.255.0</userinput> -&prompt.root; <userinput>route add default 192.168.0.1</userinput></screen> - - <para>Now that the machine is on the network, transfer your tar file. - You may be faced with a bit of a dilemma at this point - if your - flash memory part is 128 megabytes, for instance, and your tar file - is larger than 64 megabytes, you cannot have your tar file on the - flash media at the same time as you explode it - you will run out of - space. One solution to this problem, if you are using FTP, is to - untar the file while it is transferred over FTP. If you perform - your transfer in this manner, you will never have the tar file and - the tar contents on your disk at the same time:</para> - - <screen><prompt>ftp></prompt> <userinput>get tarfile.tar "| tar xvf -"</userinput></screen> - - <para>If your tarfile is gzipped, you can accomplish this as - well:</para> - - <screen><prompt>ftp></prompt> <userinput>get tarfile.tar "| zcat | tar xvf -"</userinput></screen> - - <para>After the contents of your tarred filesystem are on your flash - memory filesystem, you can unmount the flash memory and - reboot:</para> - - <screen>&prompt.root; <userinput>cd /</userinput> -&prompt.root; <userinput>umount /flash</userinput> -&prompt.root; <userinput>exit</userinput></screen> - - <para>Assuming that you configured your filesystem correctly when it - was built on the normal hard disk (with your filesystems mounted - read-only, and with the necessary options compiled into the kernel) - you should now be successfully booting your FreeBSD embedded - system.</para> - </step> - </procedure> - </sect1> - - <sect1 id="kern.flp"> - <title>Building a <filename>kern.flp</filename> Installation Floppy with - the fla Driver</title> - - <note> - <para>This section of the article is relevant only to those using - M-Systems &diskonchip; flash media.</para> - </note> - - <para>It is possible that your <filename>kern.flp</filename> boot floppy - does not have a kernel with the <devicename>fla</devicename> driver - compiled into it necessary for the system to recognize the &diskonchip;. - If you have booted off of the installation floppies and are told that no - disks are present, then you are probably lacking the - <devicename>fla</devicename> driver in your kernel.</para> - - <para>After you have built a kernel with <devicename>fla</devicename> - support that is smaller than 1.4 megabytes, you can create a custom - <filename>kern.flp</filename> floppy image with it by following these - instructions:</para> - - <procedure> - <step> - <para>Obtain an existing kern.flp image file</para> - </step> - - <step> - <para><screen>&prompt.root; <userinput>vnconfig vn0c kern.flp</userinput></screen></para> - </step> - - <step> - <para><screen>&prompt.root; <userinput>mount /dev/vn0c /mnt</userinput></screen></para> - </step> - - <step> - <para>Place your kernel file into <filename>/mnt</filename>, replacing - the existing one</para> - </step> - - <step> - <para><screen>&prompt.root; <userinput>vnconfig -d vn0c</userinput></screen></para> - </step> - </procedure> - - <para>Your <filename>kern.flp</filename> file now has your new kernel on it.</para> - </sect1> - - <sect1 id="strategies"> - <title>System Strategies for Small and Read Only Environments</title> - - <para>In <xref linkend="ro-fs">, it was pointed out that the - <filename>/var</filename> filesystem constructed by - <filename>/etc/rc.diskless2</filename> and the presence of a read-only - root filesystem causes problems with many common software packages used - with FreeBSD. In this article, suggestions for successfully running - cron, syslog, ports installations, and the Apache web server will be - provided.</para> - - <sect2> - <title>cron</title> - - <para>In <filename>/etc/rc.diskless2</filename> there is a variable - named <literal>var_dirs</literal>. This variable consists of a - space-delimited list of directories that will be created inside of - <filename>/var</filename> after it is mounted as a memory filesystem. - <filename>cron</filename> and <filename>cron/tabs</filename> are not - in that list, and without those directories, cron will complain. By - inserting <literal>cron</literal>, <literal>cron/tabs</literal>, and - perhaps even <literal>at</literal>, and <literal>at/jobs</literal> as - elements of that variable, you will facilitate the running of the - &man.cron.8; and &man.at.1; daemons.</para> - - <para>However, this still does not solve the problem of maintaining cron - tabs across reboots. When the system reboots, the - <filename>/var</filename> filesystem that is in memory will disappear - and any cron tabs you may have had in it will also disappear. - Therefore, one solution would be to create cron tabs for the users - that need them, mount your <filename>/</filename> filesystem as - read-write and copy those cron tabs to somewhere safe, like - <filename>/etc/tabs</filename>, then add a line to the end of - <filename>/etc/rc.diskless2</filename> that copies those crontabs into - <filename>/var/cron/tabs</filename> after that directory has been - created during system initialization. You may also need to add a line - that changes modes and permissions on the directories you create and - the files you copy with <filename>/etc/rc.diskless2</filename>.</para> - </sect2> - - <sect2> - <title>syslog</title> - - <para><filename>syslog.conf</filename> specifies the locations of - certain log files that exist in <filename>/var/log</filename>. These - files are not created by <filename>/etc/rc.diskless2</filename> upon - system initialization. Therefore, somewhere in - <filename>/etc/rc.diskless2</filename>, after the section that creates - the directories in <filename>/var</filename>, you will need to add - something like this:</para> - - <screen>&prompt.root; <userinput>touch /var/log/security /var/log/maillog /var/log/cron /var/log/messages</userinput> -&prompt.root; <userinput>chmod 0644 /var/log/*</userinput></screen> - - <para>You will also need to add the log directory to the list of - directories that <filename>/etc/rc.diskless2</filename> - creates.</para> - </sect2> - - <sect2> - <title>ports installation</title> - - <para>Before discussing the changes necessary to successfully use the - ports tree, a reminder is necessary regarding the read-only nature of - your filesystems on the flash media. Since they are read-only, you - will need to temporarily mount them read-write using the mount syntax - shown in <xref linkend="ro-fs">. You should always remount those - filesystems read-only when you are done with any maintenance - - unnecessary writes to the flash media could considerably shorten its - lifespan.</para> - - <para>To make it possible to enter a ports directory and successfully - run <command>make install</command>, it is necessary for the file - <filename>/var/db/port.mkversion</filename> to exist, and that it has - a correct date in it. Further, we must create a packages directory on - a non-memory filesystem that will keep track of our packages across - reboots. Because it is necessary to mount your filesystems as - read-write for the installation of a package anyway, it is sensible to - assume that an area on the flash media can also be used for package - information to be written to.</para> - - <para>First, create a package database directory. This is normally in - <filename>/var/db/pkg</filename>, but we cannot place it there as it - will disappear every time the system is booted.</para> - - <screen>&prompt.root; <userinput>mkdir /etc/pkg</userinput></screen> - - <para>Now, add a line to <filename>/etc/rc.diskless2</filename> that - links the <filename>/etc/pkg</filename> directory to - <filename>/var/db/pkg</filename>. An example:</para> - - <screen>&prompt.root; <userinput>ln -s /etc/pkg /var/db/pkg</userinput></screen> - - <para>Add another line in <filename>/etc/rc.diskless2</filename> that - creates and populates - <filename>/var/db/port.mkversion</filename></para> - - <screen>&prompt.root; <userinput>touch /var/db/port.mkversion</userinput> -&prompt.root; <userinput>chmod 0644 /var/db/port.mkversion</userinput> -&prompt.root; <userinput>echo <replaceable>20010412</replaceable> >> /var/db/port.mkversion</userinput></screen> - - <para>where <replaceable>20010412</replaceable> is a date that is - appropriate for your particular release of FreeBSD</para> - - <para>Now, any time that you mount your filesystems as read-write and - install a package, the <command>make install</command> will work - because it finds a suitable - <filename>/var/db/port.mkversion</filename>, and package information - will be written successfully to <filename>/etc/pkg</filename> (because - the filesystem will, at that time, be mounted read-write) which will - always be available to the operating system as - <filename>/var/db/pkg</filename>.</para> - </sect2> - - <sect2> - <title>Apache Web Server</title> - - <para>Apache keeps pid files and logs in - <filename><replaceable>apache_install</replaceable>/logs</filename>. - Since this directory doubtless exists on a read-only filesystem, this - will not work. It is necessary to add a new directory to the - <filename>/etc/rc.diskless2</filename> list of directories to create - in <filename>/var</filename>, to link - <filename><replaceable>apache_install</replaceable>/logs</filename> to - <filename>/var/log/apache</filename>. It is also necessary to set - permissions and ownership on this new directory.</para> - - <para>First, add the directory <literal>log/apache</literal> to the list - of directories to be created in - <filename>/etc/rc.diskless2</filename>.</para> - - <para>Second, add these commands to - <filename>/etc/rc.diskless2</filename> after the directory creation - section:</para> - - <screen>&prompt.root; <userinput>chmod 0774 /var/log/apache</userinput> -&prompt.root; <userinput>chown nobody:nobody /var/log/apache</userinput></screen> - - <para>Finally, remove the existing - <filename><replaceable>apache_install</replaceable>/logs</filename> - directory, and replace it with a link:</para> - - <screen>&prompt.root; <userinput>rm -rf (apache_install)/logs</userinput> -&prompt.root; <userinput>ln -s /var/log/apache (apache_install)/logs</userinput></screen> - </sect2> - </sect1> -</article> - |