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xntpd(8) [osf1 man page]

xntpd(8)						      System Manager's Manual							  xntpd(8)

NAME
xntpd - Network Time Protocol (NTP) daemon SYNOPSIS
/usr/sbin/xntpd [-abdgmx] [-c conffile] [-e auth_delay] [-f driftfile] [-k keyfile] [-l logfile] [-p pidfile] [-r broaddelay] [-s statdir] [-t trustedkey] [-v sysvar] [-V def_sysvar] OPTIONS
Runs in authenticate mode. Listens for broadcast NTP and synchronizes to this if available. Specify debugging mode. This option may occur multiple times, with each occurence indicating greater detail of display. Allows xntpd to correct any time difference, including differ- ences greater than 1000 seconds. Listens for multicast messages and synchronizes to them if available (requires multicast kernel). Pre- vents xntpd from setting the system time backward. In NTP version 3, the default allows xntpd to set the system time backward. Specifies an alternate configuration file. Specifies the time (in seconds) it takes to compute the NTP encryption field on this computer. Specifies the location of the drift file. Specifies the location of the file which contains the NTP authentication keys. See ntp.keys(4) for infor- mation on the authentication key file format. Specifies a log file instead of logging to syslog. Specifies the name of the file to record the daemon's process id. Specifies the default round trip delay (in seconds) to be used if the daemon cannot automatically compensate for network delay when synchronizing to broadcasts. Specifies the directory in which to create statistics files. Adds a key number to the trusted key list. Adds a system variable. Adds a system variable listed by default. DESCRIPTION
The xntpd daemon maintains a system's time-of-day in agreement with Internet standard time servers. The xntpd daemon is a complete imple- mentation of the Network Time Protocol (NTP) version 3 standard as defined by RFC 1305, but also retains compatibility with version 1 and version 2 servers as defined by RFC 1059 and RFC 1119, respectively. The xntpd daemon does all computations in fixed point arithmetic and requires no floating point code. The computations done in the proto- col and clock adjustment code are carried out with high precision and with attention to the details that might introduce systematic bias into the computations, to try to maintain an accuracy suitable for synchronizing with even the most precise external time source. The xntpd daemon reads its configuration from a file at startup time. The default configuration file is /etc/ntp.conf. The xntpd daemon can be monitored and configuration options altered while the daemon is running by using either the ntpq(8) or the xntpdc(8) program. The xntpd daemon includes support for several commercially available external reference clocks. See ntp.conf(4) for information on the use and configuration of reference clocks. The Tru64 UNIX operating system also provides the NTP_TIME and MICRO_TIME kernel options to allow greater accuracy and time resolution. See ntp_intro(7) and Network Administration for more information. FILES
Default name of the configuration file Conventional name of the drift file Conventional name of the key file SEE ALSO
Commands: ntp(1), ntpdate(8), ntpq(8), xntpdc(8) Files: ntp.conf(4), ntp.keys(4) Network Administration HISTORY
Written by Dennis Ferguson at the University of Toronto. Text amended by David Mills at the University of Delaware. xntpd(8)

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ntp_manual_setup(7)					 Miscellaneous Information Manual				       ntp_manual_setup(7)

NAME
ntp_manual_setup - Describes how to manually set up the Network Time Protocol (NTP) DESCRIPTION
Setting up the Network Time Protocol (NTP) manually includes selecting your most accurate time source and then configuring the following: Local NTP servers NTP clients You can also choose to set your system time with the rdate command, which is explained in the Setting Network Time with rdate section in this reference page. Setting Up a Local NTP Server What you must do to configure a local NTP server depends on your time source. If your time source is Internet NTP servers, see the Time Source - Internet NTP Servers section in this reference page. If your time source is a local reference clock, see the Time Source - Local Reference Clock section in this reference page. Time Source - Internet NTP Servers Use the following procedure to set up your local NTP servers if your time source is Internet NTP servers: Select three Internet primary or secondary servers for each local NTP server. Selecting a different set of Internet servers for each local server is recommended. Secondary servers are usually as reliable and accurate as primary servers. See the Network Administration manual for information on obtaining a list of Internet servers. Decide which options to the xntpd daemon you want to run. You can chose the -g option, the -l option, or both: The -g option allows the xntpd daemon to correct time differences of more than 1000 seconds between your system and that of your system's NTP servers that occur after the xntpd daemon is started. Initial time differences are corrected before the xntpd daemon is started by the ntpdate command which is run at boot time by the /sbin/init.d/settime script. If your system is sensitive to security threats, do not use the -g option. Normally, NTP logs an ini- tialization message, error messages, status messages, and several other informative messages to syslog. The -l option specifies that NTP will log only the initialization message and error messages to syslog. Edit the /etc/ntp.conf file. You must add a peer entry to the /etc/ntp.conf file for each Internet server. Each Internet server must either have an entry in the local /etc/hosts file or the hosts file distributed by BIND or NIS. The following /etc/ntp.conf file is for a local NTP server that is synchronizing its time with the fictitious Internet time servers host1, host2, and host3. The version 1 after host3 indicates that host3 is running the ntpd daemon instead of the xntpd daemon. (Servers running Tru64 UNIX run the xntpd daemon.) The line driftfile /etc/ntp.drift indicates the location of the drift file on this system. # # XNTPD Configuration File (template for NTP V3) # # # Specify a filename for the driftfile created by xntpd. # /etc/ntp.drift is the default. # driftfile /etc/ntp.drift # # # # # Specify several NTP servers and/or peers (See the xntpd # documentation for recommendations on selecting servers and peers). # NOTE: Be sure to specify the version number of the server/peer: # # peer host1 version 2 # xntpd V2 # server host2 version 1 # ntpd V1 # server host3 version 3 # xntpd V3 # # For further information on configu- ration options, see the xntpd # documentation. If you have a local accurate clock (radio clock, # etcetera), you will need to spec- ify further configuration options. # #Server and peer configuration peer host1 version 3 peer host2 version 3 peer host3 version 1 Edit the /etc/rc.config file by using the /usr/sbin/rcmgr command. The syntax for the /usr/sbin/rcmgr command is as follows: /usr/sbin/rcmgr set variable value To edit the /etc/rc.config file and add the required information, enter the following series of commands: # /usr/sbin/rcmgr set XNTPD_CONF YES # /usr/sbin/rcmgr set XNTP_SERV1 host1 # /usr/sbin/rcmgr set XNTP_SERV2 host2 # /usr/sbin/rcmgr set XNTP_SERV3 host3 # /usr/sbin/rcmgr set XNTPD_OPTS "options" Replace host1, host2, and host3 with the names of the Internet pri- mary or secondary servers that you selected in step 1. Replace options with the options you selected in step 2. You must enclose the options in quotation marks (" "). Start the xntpd daemon with the following command: # /sbin/init.d/xntpd start Verify that NTP is working by using the ntpq command with the -p option: # /usr/bin/ntpq -p For information on monitoring the xntpd daemon and using the ntpq command, see the ntpq(8) reference page. Time Source - Local Reference Clock Use the following procedure to set up your local NTP servers if your time source is a local reference clock: Choose one of your local NTP servers to be the local reference clock. The other two local NTP servers can be set up as NTP clients that use the local reference clock and each other as peers. For example, if host4, host5, and host6 are the local NTP servers and host4 is the local reference clock, then you should set them up as follows: Set up host5 as an NTP client that specifies host4 and host6 as its local NTP servers Set up host6 as an NTP client that specifies host4 and host5 as its local NTP servers Complete steps 3 through 6 only if you are setting up the local reference clock. Decide which options to the xntpd daemon you want to run. You can choose the -g option, the -l option, or both: The -g option allows the xntpd daemon to correct time differences of more than 1000 seconds between your system and that of your system's NTP servers that occur after the xntpd daemon is started. Initial time differences are corrected before the xntpd daemon is started by the ntpdate command which is run at boot time by the /sbin/init.d/settime script. If your system is sensitive to security threats, do not use the -g option. Normally, NTP logs an ini- tialization message, error messages, status messages, and several other informative messages to syslog. The -l option specifies that NTP will log only the initialization message and error messages to syslog. Edit the /etc/ntp.conf file and add the following entry: # peer 127.127.1.1 This entry allows the local reference clock to run at stratum 3. For more information about local refer- ence clocks, see the ntp.conf(4) reference page. Note that when using a local reference clock, you should never use stratum 1, since the clock may provide very inaccurate time. Edit the /etc/rc.config file by using the /usr/sbin/rcmgr command. The syntax for the /usr/sbin/rcmgr command is as follows: /usr/sbin/rcmgr set variable value To edit the /etc/rc.config file and add the required information, enter the following series of commands: # /usr/sbin/rcmgr set XNTPD_CONF YES # /usr/sbin/rcmgr set XNTP_SERV1 host4 # /usr/sbin/rcmgr set XNTP_SERV2 host5 # /usr/sbin/rcmgr set XNTP_SERV3 host6 # /usr/sbin/rcmgr set XNTPD_OPTS "options" Replace host4, host5, and host6 with the names of the hosts that you selected to be servers in step 1. Replace options with the options you selected in step 2. You must enclose the options in quota- tion marks (" "). Start the xntpd daemon with the following command: # /sbin/init.d/xntpd start Verify that NTP is working by using the ntpq command: # /usr/bin/ntpq -p For information on monitoring the xntpd daemon and using the ntpq command, see the ntpq(8) reference page. Setting Up NTP Clients Use the following procedure to set up an NTP client: Decide which options to the xntpd daemon you want to run. You can choose the -g option, the -l option, or both: The -g option allows the xntpd daemon to correct time differences of more than 1000 seconds between your system and that of your system's NTP servers that occur after the xntpd daemon is started. Initial time differences are corrected before the xntpd daemon is started by the ntpdate command which is run at boot time by the /sbin/init.d/settime script. If your system is sensitive to security threats, do not use the -g option. Normally, NTP logs an ini- tialization message, error messages, status messages, and several other informative messages to syslog. The -l option specifies that NTP will only log the initialization message and error messages to syslog. For each client, add a server entry to the /etc/ntp.conf file for each local NTP server. The following /etc/ntp.conf file is for an NTP client that is synchronizing its time with the local NTP servers host4, host5, and host6. The line driftfile /etc/ntp.drift indicates the location of the drift file on this system. # # XNTPD Configuration File (template for NTP V3) # # # Specify a filename for the driftfile created by xntpd. # /etc/ntp.drift is the default. # driftfile /etc/ntp.drift . . . server host4 version 3 server host5 version 3 server host6 version 3 Remember that each local NTP server that you specify must have an entry in either the client's /etc/hosts file or in a BIND or NIS hosts database that is searched by your system. Edit the /etc/rc.config file by using the /usr/sbin/rcmgr command. The syntax for the /usr/sbin/rcmgr command is as follows: /usr/sbin/rcmgr set variable value To edit the /etc/rc.config file and add the required information, enter the following commands: # /usr/sbin/rcmgr set XNTPD_CONF YES # /usr/sbin/rcmgr set XNTP_SERV1 host4 # /usr/sbin/rcmgr set XNTP_SERV2 host5 # /usr/sbin/rcmgr set XNTP_SERV3 host6 # /usr/sbin/rcmgr set XNTPD_OPTS "options" Replace host4, host5, and host6 with the names of three local NTP servers for your network. Replace options with the options you selected in step 1. You must enclose the options in quotation marks (" "). Enter the following command to start the xntpd daemon: # /sbin/init.d/xntpd start Verify that NTP is working by using the ntpq command with the -p option: # /usr/bin/ntpq -p For information on monitoring the xntpd daemon and using the ntpq command, see the ntpq(8) reference page. Setting Network Time with rdate For your system to use the rdate command to set its time to the average network time when it starts, you must add an entry for rdate to the /etc/rc.config file. If your network uses the Network Time Protocol (NTP) time service you might still want to put the rdate entry in the /etc/rc.config file; if NTP hosts are unreachable, the system's time will still be set. If NTP hosts are reachable, the ntpdate command, which runs after the rdate command, will set the time to NTP time before starting the xntpd daemon. You must use the rcmgr command to edit the /etc/rc.config file. Enter the following command to add an entry for the rdate command to the /etc/rc.config file: # /usr/sbin/rcmgr set RDATE_CONF YES RELATED INFORMATION
Commands: ntp(1), timedsetup(8), xntpdc(8).. Daemons: timed(8), xntpd(8). Routines: ctime(3). Files: ntp.conf(4). Introduction: ntp_intro(7). Network Administration delim off ntp_manual_setup(7)
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