Check NTP Server/Clients

[Evans Kelley]

Hello all,

I was asked to setup NTP on a few new servers that we recently received; we already have NTP server/clients using NTP on other systems. My question is, how do I find out which ones are the servers? Because from what I am reading you have a NTP Time Server Hierarchy (One Stratum 1 Server going out to an external clock, which is how I believe they have set this up)
My other question is how do I fully test and make sure the clients are working property with the NTP servers.
Thanks in advance for all your help.
ekelley

[Jeff Schussele · Accepted solution]

Hi Evans,

1) Check an NTP client's /etc/ntp.conf file. It'll list it's servers in there. Of course your server will be a client to an external source(s) & it's ntp.conf file will list them.

2) To check whether it's working on the clients A) run #ps -ef | grep ntp to see whether xntpd daemon is running B) Check /etc/rc.config.d/netdaemons & insure XNTPD=1 to make sure it starts at boot C) Check the clients /etc/ntp.conf file for the proper config D) Check the syslog.log to see the adjustments E) Compare it's time to your NTP server - should not be more than 128 ms difference.

HTH,
Jeff

[Brian M Rawlings]

Nicely summarized, Jeff.

One quick way to test timestamps on other servers, provided you have 'rexec' trust between them, is to do:

date; rexec date

You will get back two date/time stamps. If NTP is running correctly, and you don't have horrendous network delays or extremely busy servers, you should see them identical (to the second), or at most one second difference (depending on rounding functions and timing of your command).

Later... --bmr

[James R. Ferguson]

Hi:

One of the easist ways to check the viability of a NTP setup is to use 'ntpq'. See the man pages for more information. Run 'ntpq -pn' or drop the 'n' flag to resolve IPAddress to DNS name (as available).

For more information on 'xntp' (NTP) and 'ntpq' see chapter-7 of "Installing and Administering Internet Services":

http://docs.hp.com/hpux/onlinedocs/B2355-90685/B2355-90685.html

Regards!

...JRF...

[Evans Kelley]

Thank you all for your help.