I have server A running a daily cron to sync its time using ntpd:
e.g.

ntpd -qg (it simply sets its time and then exits)

I would like to sync server B's system time to server A.

Specifically:
1. Server B is not connected to internet so it cannot sync with the same time servers as server A is doing
2. I would like to avoid perpetually running the ntpd service on server A as I feel this is overkill - I just want to update once a day and that's it.

So is it possible to write a simple script that updates server B's time to that of server A without having to run server B as a ntp client of server A and keep server A running as an ntpd server?

Thanks for helping me figure out if this is possible. Or, if anyone can think of a better idea to accomplish what I am looking for I would love to hear it.

Thanks

I guess you could run some sort of script that grabbed the time on Server A and then did some string manipulations to set the time on Server B. But the easiest, simplest method is running ntpd. I haven't seen many overhead issues with ntp servers.

I was concerned about running an extra process for one, but also whether it is a security risk to run ntpd on a production webserver? Do I have to leave port 123 open to do that?

Ok I'm assuming that the servers connect over the local network as Server B can not connect to the internet. If that is the case you would only have to have open 123 on the local network. You can tighten that down even further using iptables.

You can also use the ntp.conf to set restrictions on what systems Server A can connect to here's a link to walk you through it. Personally though I just use IPTables.

http://support.ntp.org/bin/view/Supp...ection_6.5.1.2.