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diff --git a/usr.sbin/ntp/doc/ntpd.8 b/usr.sbin/ntp/doc/ntpd.8 deleted file mode 100644 index 07cb6d5578c6..000000000000 --- a/usr.sbin/ntp/doc/ntpd.8 +++ /dev/null @@ -1,910 +0,0 @@ -.Dd August 14 2018 -.Dt NTPD 8 User Commands -.Os -.\" EDIT THIS FILE WITH CAUTION (ntpd-opts.mdoc) -.\" -.\" $FreeBSD$ -.\" -.\" It has been AutoGen-ed August 14, 2018 at 08:29:20 AM by AutoGen 5.18.5 -.\" From the definitions ntpd-opts.def -.\" and the template file agmdoc-cmd.tpl -.Sh NAME -.Nm ntpd -.Nd NTP daemon program -.Sh SYNOPSIS -.Nm -.\" Mixture of short (flag) options and long options -.Op Fl flags -.Op Fl flag Op Ar value -.Op Fl \-option\-name Ns Oo Oo Ns "=| " Oc Ns Ar value Oc -[ <server1> ... <serverN> ] -.Pp -.Sh DESCRIPTION -The -.Nm -utility is an operating system daemon which sets -and maintains the system time of day in synchronism with Internet -standard time servers. -It is a complete implementation of the -Network Time Protocol (NTP) version 4, as defined by RFC\-5905, -but also retains compatibility with -version 3, as defined by RFC\-1305, and versions 1 -and 2, as defined by RFC\-1059 and RFC\-1119, respectively. -.Pp -The -.Nm -utility does most computations in 64\-bit floating point -arithmetic and does relatively clumsy 64\-bit fixed point operations -only when necessary to preserve the ultimate precision, about 232 -picoseconds. -While the ultimate precision is not achievable with -ordinary workstations and networks of today, it may be required -with future gigahertz CPU clocks and gigabit LANs. -.Pp -Ordinarily, -.Nm -reads the -.Xr ntp.conf 5 -configuration file at startup time in order to determine the -synchronization sources and operating modes. -It is also possible to -specify a working, although limited, configuration entirely on the -command line, obviating the need for a configuration file. -This may -be particularly useful when the local host is to be configured as a -broadcast/multicast client, with all peers being determined by -listening to broadcasts at run time. -.Pp -If NetInfo support is built into -.Nm , -then -.Nm -will attempt to read its configuration from the -NetInfo if the default -.Xr ntp.conf 5 -file cannot be read and no file is -specified by the -.Fl c -option. -.Pp -Various internal -.Nm -variables can be displayed and -configuration options altered while the -.Nm -is running -using the -.Xr ntpq 8 -and -.Xr ntpdc 8 -utility programs. -.Pp -When -.Nm -starts it looks at the value of -.Xr umask 2 , -and if zero -.Nm -will set the -.Xr umask 2 -to 022. -.Sh "OPTIONS" -.Bl -tag -.It Fl 4 , Fl \-ipv4 -Force IPv4 DNS name resolution. -This option must not appear in combination with any of the following options: -ipv6. -.sp -Force DNS resolution of following host names on the command line -to the IPv4 namespace. -.It Fl 6 , Fl \-ipv6 -Force IPv6 DNS name resolution. -This option must not appear in combination with any of the following options: -ipv4. -.sp -Force DNS resolution of following host names on the command line -to the IPv6 namespace. -.It Fl a , Fl \-authreq -Require crypto authentication. -This option must not appear in combination with any of the following options: -authnoreq. -.sp -Require cryptographic authentication for broadcast client, -multicast client and symmetric passive associations. -This is the default. -.It Fl A , Fl \-authnoreq -Do not require crypto authentication. -This option must not appear in combination with any of the following options: -authreq. -.sp -Do not require cryptographic authentication for broadcast client, -multicast client and symmetric passive associations. -This is almost never a good idea. -.It Fl b , Fl \-bcastsync -Allow us to sync to broadcast servers. -.sp -.It Fl c Ar string , Fl \-configfile Ns = Ns Ar string -configuration file name. -.sp -The name and path of the configuration file, -\fI/etc/ntp.conf\fP -by default. -.It Fl d , Fl \-debug\-level -Increase debug verbosity level. -This option may appear an unlimited number of times. -.sp -.It Fl D Ar number , Fl \-set\-debug\-level Ns = Ns Ar number -Set the debug verbosity level. -This option may appear an unlimited number of times. -This option takes an integer number as its argument. -.sp -.It Fl f Ar string , Fl \-driftfile Ns = Ns Ar string -frequency drift file name. -.sp -The name and path of the frequency file, -\fI/etc/ntp.drift\fP -by default. -This is the same operation as the -\fBdriftfile\fP \fIdriftfile\fP -configuration specification in the -\fI/etc/ntp.conf\fP -file. -.It Fl g , Fl \-panicgate -Allow the first adjustment to be Big. -This option may appear an unlimited number of times. -.sp -Normally, -\fBntpd\fP -exits with a message to the system log if the offset exceeds the panic threshold, which is 1000 s by default. This option allows the time to be set to any value without restriction; however, this can happen only once. If the threshold is exceeded after that, -\fBntpd\fP -will exit with a message to the system log. This option can be used with the -\fB\-q\fP -and -\fB\-x\fP -options. -See the -\fBtinker\fP -configuration file directive for other options. -.It Fl G , Fl \-force\-step\-once -Step any initial offset correction.. -.sp -Normally, -\fBntpd\fP -steps the time if the time offset exceeds the step threshold, -which is 128 ms by default, and otherwise slews the time. -This option forces the initial offset correction to be stepped, -so the highest time accuracy can be achieved quickly. -However, this may also cause the time to be stepped back -so this option must not be used if -applications requiring monotonic time are running. -See the \fBtinker\fP configuration file directive for other options. -.It Fl i Ar string , Fl \-jaildir Ns = Ns Ar string -Jail directory. -.sp -Chroot the server to the directory -\fIjaildir\fP -. -This option also implies that the server attempts to drop root privileges at startup. -You may need to also specify a -\fB\-u\fP -option. -This option is only available if the OS supports adjusting the clock -without full root privileges. -This option is supported under NetBSD (configure with -\fB\-\-enable\-clockctl\fP) or Linux (configure with -\fB\-\-enable\-linuxcaps\fP) or Solaris (configure with \fB\-\-enable\-solarisprivs\fP). -.It Fl I Ar iface , Fl \-interface Ns = Ns Ar iface -Listen on an interface name or address. -This option may appear an unlimited number of times. -.sp -Open the network address given, or all the addresses associated with the -given interface name. This option may appear multiple times. This option -also implies not opening other addresses, except wildcard and localhost. -This option is deprecated. Please consider using the configuration file -\fBinterface\fP command, which is more versatile. -.It Fl k Ar string , Fl \-keyfile Ns = Ns Ar string -path to symmetric keys. -.sp -Specify the name and path of the symmetric key file. -\fI/etc/ntp.keys\fP -is the default. -This is the same operation as the -\fBkeys\fP \fIkeyfile\fP -configuration file directive. -.It Fl l Ar string , Fl \-logfile Ns = Ns Ar string -path to the log file. -.sp -Specify the name and path of the log file. -The default is the system log file. -This is the same operation as the -\fBlogfile\fP \fIlogfile\fP -configuration file directive. -.It Fl L , Fl \-novirtualips -Do not listen to virtual interfaces. -.sp -Do not listen to virtual interfaces, defined as those with -names containing a colon. This option is deprecated. Please -consider using the configuration file \fBinterface\fP command, which -is more versatile. -.It Fl M , Fl \-modifymmtimer -Modify Multimedia Timer (Windows only). -.sp -Set the Windows Multimedia Timer to highest resolution. This -ensures the resolution does not change while ntpd is running, -avoiding timekeeping glitches associated with changes. -.It Fl n , Fl \-nofork -Do not fork. -This option must not appear in combination with any of the following options: -wait\-sync. -.sp -.It Fl N , Fl \-nice -Run at high priority. -.sp -To the extent permitted by the operating system, run -\fBntpd\fP -at the highest priority. -.It Fl p Ar string , Fl \-pidfile Ns = Ns Ar string -path to the PID file. -.sp -Specify the name and path of the file used to record -\fBntpd\fP's -process ID. -This is the same operation as the -\fBpidfile\fP \fIpidfile\fP -configuration file directive. -.It Fl P Ar number , Fl \-priority Ns = Ns Ar number -Process priority. -This option takes an integer number as its argument. -.sp -To the extent permitted by the operating system, run -\fBntpd\fP -at the specified -\fBsched_setscheduler(SCHED_FIFO)\fP -priority. -.It Fl q , Fl \-quit -Set the time and quit. -This option must not appear in combination with any of the following options: -saveconfigquit, wait\-sync. -.sp -\fBntpd\fP -will not daemonize and will exit after the clock is first -synchronized. This behavior mimics that of the -\fBntpdate\fP -program, which will soon be replaced with a shell script. -The -\fB\-g\fP -and -\fB\-x\fP -options can be used with this option. -Note: The kernel time discipline is disabled with this option. -.It Fl r Ar string , Fl \-propagationdelay Ns = Ns Ar string -Broadcast/propagation delay. -.sp -Specify the default propagation delay from the broadcast/multicast server to this client. This is necessary only if the delay cannot be computed automatically by the protocol. -.It Fl \-saveconfigquit Ns = Ns Ar string -Save parsed configuration and quit. -This option must not appear in combination with any of the following options: -quit, wait\-sync. -.sp -Cause \fBntpd\fP to parse its startup configuration file and save an -equivalent to the given filename and exit. This option was -designed for automated testing. -.It Fl s Ar string , Fl \-statsdir Ns = Ns Ar string -Statistics file location. -.sp -Specify the directory path for files created by the statistics facility. -This is the same operation as the -\fBstatsdir\fP \fIstatsdir\fP -configuration file directive. -.It Fl t Ar tkey , Fl \-trustedkey Ns = Ns Ar tkey -Trusted key number. -This option may appear an unlimited number of times. -.sp -Add the specified key number to the trusted key list. -.It Fl u Ar string , Fl \-user Ns = Ns Ar string -Run as userid (or userid:groupid). -.sp -Specify a user, and optionally a group, to switch to. -This option is only available if the OS supports adjusting the clock -without full root privileges. -This option is supported under NetBSD (configure with -\fB\-\-enable\-clockctl\fP) or Linux (configure with -\fB\-\-enable\-linuxcaps\fP) or Solaris (configure with \fB\-\-enable\-solarisprivs\fP). -.It Fl U Ar number , Fl \-updateinterval Ns = Ns Ar number -interval in seconds between scans for new or dropped interfaces. -This option takes an integer number as its argument. -.sp -Give the time in seconds between two scans for new or dropped interfaces. -For systems with routing socket support the scans will be performed shortly after the interface change -has been detected by the system. -Use 0 to disable scanning. 60 seconds is the minimum time between scans. -.It Fl \-var Ns = Ns Ar nvar -make ARG an ntp variable (RW). -This option may appear an unlimited number of times. -.sp -.It Fl \-dvar Ns = Ns Ar ndvar -make ARG an ntp variable (RW|DEF). -This option may appear an unlimited number of times. -.sp -.It Fl w Ar number , Fl \-wait\-sync Ns = Ns Ar number -Seconds to wait for first clock sync. -This option must not appear in combination with any of the following options: -nofork, quit, saveconfigquit. -This option takes an integer number as its argument. -.sp -If greater than zero, alters \fBntpd\fP's behavior when forking to -daemonize. Instead of exiting with status 0 immediately after -the fork, the parent waits up to the specified number of -seconds for the child to first synchronize the clock. The exit -status is zero (success) if the clock was synchronized, -otherwise it is \fBETIMEDOUT\fP. -This provides the option for a script starting \fBntpd\fP to easily -wait for the first set of the clock before proceeding. -.It Fl x , Fl \-slew -Slew up to 600 seconds. -.sp -Normally, the time is slewed if the offset is less than the step threshold, which is 128 ms by default, and stepped if above the threshold. -This option sets the threshold to 600 s, which is well within the accuracy window to set the clock manually. -Note: Since the slew rate of typical Unix kernels is limited to 0.5 ms/s, each second of adjustment requires an amortization interval of 2000 s. -Thus, an adjustment as much as 600 s will take almost 14 days to complete. -This option can be used with the -\fB\-g\fP -and -\fB\-q\fP -options. -See the -\fBtinker\fP -configuration file directive for other options. -Note: The kernel time discipline is disabled with this option. -.It Fl \-usepcc -Use CPU cycle counter (Windows only). -.sp -Attempt to substitute the CPU counter for \fBQueryPerformanceCounter\fP. -The CPU counter and \fBQueryPerformanceCounter\fP are compared, and if -they have the same frequency, the CPU counter (RDTSC on x86) is -used directly, saving the overhead of a system call. -.It Fl \-pccfreq Ns = Ns Ar string -Force CPU cycle counter use (Windows only). -.sp -Force substitution the CPU counter for \fBQueryPerformanceCounter\fP. -The CPU counter (RDTSC on x86) is used unconditionally with the -given frequency (in Hz). -.It Fl m , Fl \-mdns -Register with mDNS as a NTP server. -.sp -Registers as an NTP server with the local mDNS server which allows -the server to be discovered via mDNS client lookup. -.It Fl \&? , Fl \-help -Display usage information and exit. -.It Fl \&! , Fl \-more\-help -Pass the extended usage information through a pager. -.It Fl \-version Op Brq Ar v|c|n -Output version of program and exit. The default mode is `v', a simple -version. The `c' mode will print copyright information and `n' will -print the full copyright notice. -.El -.Sh "OPTION PRESETS" -Any option that is not marked as \fInot presettable\fP may be preset -by loading values from environment variables named: -.nf - \fBNTPD_<option\-name>\fP or \fBNTPD\fP -.fi -.ad -.Sh USAGE -.Ss "How NTP Operates" -The -.Nm -utility operates by exchanging messages with -one or more configured servers over a range of designated poll intervals. -When -started, whether for the first or subsequent times, the program -requires several exchanges from the majority of these servers so -the signal processing and mitigation algorithms can accumulate and -groom the data and set the clock. -In order to protect the network -from bursts, the initial poll interval for each server is delayed -an interval randomized over a few seconds. -At the default initial poll -interval of 64s, several minutes can elapse before the clock is -set. -This initial delay to set the clock -can be safely and dramatically reduced using the -.Cm iburst -keyword with the -.Ic server -configuration -command, as described in -.Xr ntp.conf 5 . -.Pp -Most operating systems and hardware of today incorporate a -time\-of\-year (TOY) chip to maintain the time during periods when -the power is off. -When the machine is booted, the chip is used to -initialize the operating system time. -After the machine has -synchronized to a NTP server, the operating system corrects the -chip from time to time. -In the default case, if -.Nm -detects that the time on the host -is more than 1000s from the server time, -.Nm -assumes something must be terribly wrong and the only -reliable action is for the operator to intervene and set the clock -by hand. -(Reasons for this include there is no TOY chip, -or its battery is dead, or that the TOY chip is just of poor quality.) -This causes -.Nm -to exit with a panic message to -the system log. -The -.Fl g -option overrides this check and the -clock will be set to the server time regardless of the chip time -(up to 68 years in the past or future \(em -this is a limitation of the NTPv4 protocol). -However, and to protect against broken hardware, such as when the -CMOS battery fails or the clock counter becomes defective, once the -clock has been set an error greater than 1000s will cause -.Nm -to exit anyway. -.Pp -Under ordinary conditions, -.Nm -adjusts the clock in -small steps so that the timescale is effectively continuous and -without discontinuities. -Under conditions of extreme network -congestion, the roundtrip delay jitter can exceed three seconds and -the synchronization distance, which is equal to one\-half the -roundtrip delay plus error budget terms, can become very large. -The -.Nm -algorithms discard sample offsets exceeding 128 ms, -unless the interval during which no sample offset is less than 128 -ms exceeds 900s. -The first sample after that, no matter what the -offset, steps the clock to the indicated time. -In practice this -reduces the false alarm rate where the clock is stepped in error to -a vanishingly low incidence. -.Pp -As the result of this behavior, once the clock has been set it -very rarely strays more than 128 ms even under extreme cases of -network path congestion and jitter. -Sometimes, in particular when -.Nm -is first started without a valid drift file -on a system with a large intrinsic drift -the error might grow to exceed 128 ms, -which would cause the clock to be set backwards -if the local clock time is more than 128 s -in the future relative to the server. -In some applications, this behavior may be unacceptable. -There are several solutions, however. -If the -.Fl x -option is included on the command line, the clock will -never be stepped and only slew corrections will be used. -But this choice comes with a cost that -should be carefully explored before deciding to use -the -.Fl x -option. -The maximum slew rate possible is limited -to 500 parts\-per\-million (PPM) as a consequence of the correctness -principles on which the NTP protocol and algorithm design are -based. -As a result, the local clock can take a long time to -converge to an acceptable offset, about 2,000 s for each second the -clock is outside the acceptable range. -During this interval the -local clock will not be consistent with any other network clock and -the system cannot be used for distributed applications that require -correctly synchronized network time. -.Pp -In spite of the above precautions, sometimes when large -frequency errors are present the resulting time offsets stray -outside the 128\-ms range and an eventual step or slew time -correction is required. -If following such a correction the -frequency error is so large that the first sample is outside the -acceptable range, -.Nm -enters the same state as when the -.Pa ntp.drift -file is not present. -The intent of this behavior -is to quickly correct the frequency and restore operation to the -normal tracking mode. -In the most extreme cases -(the host -.Cm time.ien.it -comes to mind), there may be occasional -step/slew corrections and subsequent frequency corrections. -It -helps in these cases to use the -.Cm burst -keyword when -configuring the server, but -ONLY -when you have permission to do so from the owner of the target host. -.Pp -Finally, -in the past many startup scripts would run -.Xr ntpdate 8 -or -.Xr sntp 8 -to get the system clock close to correct before starting -.Xr ntpd 8 , -but this was never more than a mediocre hack and is no longer needed. -If you are following the instructions in -.Sx "Starting NTP (Best Current Practice)" -and you still need to set the system time before starting -.Nm , -please open a bug report and document what is going on, -and then look at using -.Xr sntp 8 -if you really need to set the clock before starting -.Nm . -.Pp -There is a way to start -.Xr ntpd 8 -that often addresses all of the problems mentioned above. -.Ss "Starting NTP (Best Current Practice)" -First, use the -.Cm iburst -option on your -.Cm server -entries. -.Pp -If you can also keep a good -.Pa ntp.drift -file then -.Xr ntpd 8 -will effectively "warm\-start" and your system's clock will -be stable in under 11 seconds' time. -.Pp -As soon as possible in the startup sequence, start -.Xr ntpd 8 -with at least the -.Fl g -and perhaps the -.Fl N -options. -Then, -start the rest of your "normal" processes. -This will give -.Xr ntpd 8 -as much time as possible to get the system's clock synchronized and stable. -.Pp -Finally, -if you have processes like -.Cm dovecot -or database servers -that require -monotonically\-increasing time, -run -.Xr ntp\-wait 1ntp\-waitmdoc -as late as possible in the boot sequence -(perhaps with the -.Fl v -flag) -and after -.Xr ntp\-wait 1ntp\-waitmdoc -exits successfully -it is as safe as it will ever be to start any process that require -stable time. -.Ss "Frequency Discipline" -The -.Nm -behavior at startup depends on whether the -frequency file, usually -.Pa ntp.drift , -exists. -This file -contains the latest estimate of clock frequency error. -When the -.Nm -is started and the file does not exist, the -.Nm -enters a special mode designed to quickly adapt to -the particular system clock oscillator time and frequency error. -This takes approximately 15 minutes, after which the time and -frequency are set to nominal values and the -.Nm -enters -normal mode, where the time and frequency are continuously tracked -relative to the server. -After one hour the frequency file is -created and the current frequency offset written to it. -When the -.Nm -is started and the file does exist, the -.Nm -frequency is initialized from the file and enters normal mode -immediately. -After that the current frequency offset is written to -the file at hourly intervals. -.Ss "Operating Modes" -The -.Nm -utility can operate in any of several modes, including -symmetric active/passive, client/server broadcast/multicast and -manycast, as described in the -.Qq Association Management -page -(available as part of the HTML documentation -provided in -.Pa /usr/share/doc/ntp ) . -It normally operates continuously while -monitoring for small changes in frequency and trimming the clock -for the ultimate precision. -However, it can operate in a one\-time -mode where the time is set from an external server and frequency is -set from a previously recorded frequency file. -A -broadcast/multicast or manycast client can discover remote servers, -compute server\-client propagation delay correction factors and -configure itself automatically. -This makes it possible to deploy a -fleet of workstations without specifying configuration details -specific to the local environment. -.Pp -By default, -.Nm -runs in continuous mode where each of -possibly several external servers is polled at intervals determined -by an intricate state machine. -The state machine measures the -incidental roundtrip delay jitter and oscillator frequency wander -and determines the best poll interval using a heuristic algorithm. -Ordinarily, and in most operating environments, the state machine -will start with 64s intervals and eventually increase in steps to -1024s. -A small amount of random variation is introduced in order to -avoid bunching at the servers. -In addition, should a server become -unreachable for some time, the poll interval is increased in steps -to 1024s in order to reduce network overhead. -.Pp -In some cases it may not be practical for -.Nm -to run continuously. -A common workaround has been to run the -.Xr ntpdate 8 -or -.Xr sntp 8 -programs from a -.Xr cron 8 -job at designated -times. -However, these programs do not have the crafted signal -processing, error checking or mitigation algorithms of -.Nm . -The -.Fl q -option is intended for this purpose. -Setting this option will cause -.Nm -to exit just after -setting the clock for the first time. -The procedure for initially -setting the clock is the same as in continuous mode; most -applications will probably want to specify the -.Cm iburst -keyword with the -.Ic server -configuration command. -With this -keyword a volley of messages are exchanged to groom the data and -the clock is set in about 10 s. -If nothing is heard after a -couple of minutes, the daemon times out and exits. -After a suitable -period of mourning, the -.Xr ntpdate 8 -program will be -retired. -.Pp -When kernel support is available to discipline the clock -frequency, which is the case for stock Solaris, Tru64, Linux and -.Fx , -a useful feature is available to discipline the clock -frequency. -First, -.Nm -is run in continuous mode with -selected servers in order to measure and record the intrinsic clock -frequency offset in the frequency file. -It may take some hours for -the frequency and offset to settle down. -Then the -.Nm -is -stopped and run in one\-time mode as required. -At each startup, the -frequency is read from the file and initializes the kernel -frequency. -.Ss "Poll Interval Control" -This version of NTP includes an intricate state machine to -reduce the network load while maintaining a quality of -synchronization consistent with the observed jitter and wander. -There are a number of ways to tailor the operation in order enhance -accuracy by reducing the interval or to reduce network overhead by -increasing it. -However, the user is advised to carefully consider -the consequences of changing the poll adjustment range from the -default minimum of 64 s to the default maximum of 1,024 s. -The -default minimum can be changed with the -.Ic tinker -.Cm minpoll -command to a value not less than 16 s. -This value is used for all -configured associations, unless overridden by the -.Cm minpoll -option on the configuration command. -Note that most device drivers -will not operate properly if the poll interval is less than 64 s -and that the broadcast server and manycast client associations will -also use the default, unless overridden. -.Pp -In some cases involving dial up or toll services, it may be -useful to increase the minimum interval to a few tens of minutes -and maximum interval to a day or so. -Under normal operation -conditions, once the clock discipline loop has stabilized the -interval will be increased in steps from the minimum to the -maximum. -However, this assumes the intrinsic clock frequency error -is small enough for the discipline loop correct it. -The capture -range of the loop is 500 PPM at an interval of 64s decreasing by a -factor of two for each doubling of interval. -At a minimum of 1,024 -s, for example, the capture range is only 31 PPM. -If the intrinsic -error is greater than this, the drift file -.Pa ntp.drift -will -have to be specially tailored to reduce the residual error below -this limit. -Once this is done, the drift file is automatically -updated once per hour and is available to initialize the frequency -on subsequent daemon restarts. -.Ss "The huff\-n'\-puff Filter" -In scenarios where a considerable amount of data are to be -downloaded or uploaded over telephone modems, timekeeping quality -can be seriously degraded. -This occurs because the differential -delays on the two directions of transmission can be quite large. -In -many cases the apparent time errors are so large as to exceed the -step threshold and a step correction can occur during and after the -data transfer is in progress. -.Pp -The huff\-n'\-puff filter is designed to correct the apparent time -offset in these cases. -It depends on knowledge of the propagation -delay when no other traffic is present. -In common scenarios this -occurs during other than work hours. -The filter maintains a shift -register that remembers the minimum delay over the most recent -interval measured usually in hours. -Under conditions of severe -delay, the filter corrects the apparent offset using the sign of -the offset and the difference between the apparent delay and -minimum delay. -The name of the filter reflects the negative (huff) -and positive (puff) correction, which depends on the sign of the -offset. -.Pp -The filter is activated by the -.Ic tinker -command and -.Cm huffpuff -keyword, as described in -.Xr ntp.conf 5 . -.Sh "ENVIRONMENT" -See \fBOPTION PRESETS\fP for configuration environment variables. -.Sh FILES -.Bl -tag -width /etc/ntp.drift -compact -.It Pa /etc/ntp.conf -the default name of the configuration file -.It Pa /etc/ntp.drift -the default name of the drift file -.It Pa /etc/ntp.keys -the default name of the key file -.El -.Sh "EXIT STATUS" -One of the following exit values will be returned: -.Bl -tag -.It 0 " (EXIT_SUCCESS)" -Successful program execution. -.It 1 " (EXIT_FAILURE)" -The operation failed or the command syntax was not valid. -.It 70 " (EX_SOFTWARE)" -libopts had an internal operational error. Please report -it to autogen\-users@lists.sourceforge.net. Thank you. -.El -.Sh "SEE ALSO" -.Xr ntp.conf 5 , -.Xr ntpdate 8 , -.Xr ntpdc 8 , -.Xr ntpq 8 , -.Xr sntp 8 -.Pp -In addition to the manual pages provided, -comprehensive documentation is available on the world wide web -at -.Li http://www.ntp.org/ . -A snapshot of this documentation is available in HTML format in -.Pa /usr/share/doc/ntp . -.Rs -.%A David L. Mills -.%T Network Time Protocol (Version 1) -.%O RFC1059 -.Re -.Rs -.%A David L. Mills -.%T Network Time Protocol (Version 2) -.%O RFC1119 -.Re -.Rs -.%A David L. Mills -.%T Network Time Protocol (Version 3) -.%O RFC1305 -.Re -.Rs -.%A David L. Mills -.%A J. Martin, Ed. -.%A J. Burbank -.%A W. Kasch -.%T Network Time Protocol Version 4: Protocol and Algorithms Specification -.%O RFC5905 -.Re -.Rs -.%A David L. Mills -.%A B. Haberman, Ed. -.%T Network Time Protocol Version 4: Autokey Specification -.%O RFC5906 -.Re -.Rs -.%A H. Gerstung -.%A C. Elliott -.%A B. Haberman, Ed. -.%T Definitions of Managed Objects for Network Time Protocol Version 4: (NTPv4) -.%O RFC5907 -.Re -.Rs -.%A R. Gayraud -.%A B. Lourdelet -.%T Network Time Protocol (NTP) Server Option for DHCPv6 -.%O RFC5908 -.Re -.Sh "AUTHORS" -The University of Delaware and Network Time Foundation -.Sh "COPYRIGHT" -Copyright (C) 1992\-2017 The University of Delaware and Network Time Foundation all rights reserved. -This program is released under the terms of the NTP license, <http://ntp.org/license>. -.Sh BUGS -The -.Nm -utility has gotten rather fat. -While not huge, it has gotten -larger than might be desirable for an elevated\-priority -.Nm -running on a workstation, particularly since many of -the fancy features which consume the space were designed more with -a busy primary server, rather than a high stratum workstation in -mind. -.Pp -Please send bug reports to: http://bugs.ntp.org, bugs@ntp.org -.Sh NOTES -Portions of this document came from FreeBSD. -.Pp -This manual page was \fIAutoGen\fP\-erated from the \fBntpd\fP -option definitions. |