Is NTP necessary

[jwb]

Does unixshell operate with Xen's independent_wallclock? That is, do the domains track the domain 0 RTC or are they independent? Does unixshell run an ntpd in domain 0?

[gilesmorant]

If you look back at the previous forum posts on NTP you will get a good idea of the background.

Basically, the time on the Xen servers should not be trusted- it's normally ok to within 2 minutes, but no more.
You should set the wall_clock var to 1, and run ntp/chrony yourself.

Matta,
if this has changed, please let us know! I need subsecond accuracy for my work, which I have attained by running my own chrony process.

[matta]

We are running ntp on the hosts so it should always be in sync, there is no opposition to customers maintaining their own time though.

[gilesmorant]

Matta,
some time ago you were running a cron job with ntpdate- can you confirm this is now a proper NTP service? I recall there was some problem running full NTP.