Drifting Virtual Clocks / Multiple VM's

[rbc]

I'm having problems with drifting clocks under Parallels Desktop for Mac.

The host is a dedicated Intel Mac Mini with 2GB's of memory running Mac OS-X 10.4.7. I'm running three virtual machines. They run FreeBSD 6.1 under Parallels build 1848, 12 June 2006. The virtual memory configurations are 384MB, 384MB and 256MB. The virtual system drives are located on a Maxtor OneTouch III External drive connected via USB2. The drive is 7200RPM, 500GB with a 16MB cache.

The system clocks under FreeBSD frequently drift tens of minutes in a single day. Two of the virtual systems are heavily loaded about twice a day doing large postgres databsase updates that run for a couple of hours.

Has anyone seen this kind of problem, or have a suggested solution?

Thanks,

--Bruce

[joem]

This problem with a Windows guest is solved by installing Parallels tools to activate time sync. I'm not using *Nix except OSX so I don't know if there's a *NIX solution.

[rbc]

I did try to ntpdate one of the virtual freebsd machines, but it came back with some kind of permission denied error... Rebooting always seems to fix the time however.

[darkone]

i think you have to run ntpdate using sudo for it to update the system time.

I run it as root from cron every 30 mins on my virtual machines and it works fine.

[rbc]

I ran it as root before. In my case the permission denied came from ipfw. Oops...... Thanks for the tip! ntpd is working just fine now that I added the ipfw rule.