NTP Client Configuration

# # /etc/ntp.conf # for a client in # .rz.fh-augsburg.de # peer 127.127.1.1 server kim # 141.82.30.150 server kipling # 141.82.30.145 server balzambo # 141.82.30.146 server compact # 141.82.30.244 restrict default ignore notrust nomodify restrict 127.0.0.1 restrict 141.82.30.153 # this host !!! restrict 127.127.0.0 mask 255.255.0.0 restrict 141.82.0.0 mask 255.255.0.0 nomodify restrict 141.82.30.251 # tick restrict 141.82.30.252 # tock restrict 141.82.30.130 # rudyard restrict 141.82.30.150 # kim restrict 141.82.30.145 # kipling restrict 141.82.30.146 # balzambo restrict 141.82.30.244 # compact driftfile /etc/ntp.drift #logconfig =syncall #logfile /var/log/ntp.log

This is a ntp.conf file for a stratum-4 client in our department network.

The internal PC clock is peered to let it be set by the NTP daemon and to refer to it when this host is cut off the net.

Accurate time is gotten from four of our distribution servers. There may be others in the future, and you should replace these by your own. We use the bare hostnames since we are in our domain and rely upon DNS. We could use the IP addresses instead which are needed in any case for the following access restrictions.

All accesses to the NTP daemon on this host are defeated unless explicitely allowed (in the following lines).

The local loop is completely unrestricted as is this host itself and any clock device attached to it. You MUST unrestrict the host, so change our IP address to yours!

restrict 141.82.0.0 mask 255.255.0.0 nomodify restrict 141.82.30.251 # tick restrict 141.82.30.252 # tock restrict 141.82.30.130 # rudyard restrict 141.82.30.150 # kim restrict 141.82.30.145 # kipling restrict 141.82.30.146 # balzambo restrict 141.82.30.244 # compact

Any other host in our campus network can freely access this host as far as NTP is involved, but they are not allowed to modify the configuration. Our reference servers (stratum 2) and distribution servers (stratum 3) can do that for administration purposes. Replace with your network and server addresses!

The clock drift is written to a file every hour. This reduces clock stabilization time from hours to minutes in case of restart.

All synchronization events are logged in a text file. A simple client like this doesn't need logging, so we commented it out. But in case the daemon loses synchronization it may be useful to have this log.