Time falling out of sync

[xulfer]

The time in my guests seem to be off quite frequently. This has happened in both KVM, and OpenVZ guests. The host time remains accurate. The guests are supposed to get their time from the host as far as I know so I have know idea how to even correct this issue. Migrating seems to fix the problem, but I'd like to figure out a way to fix it without spending hours migrating.

Restarting the guests, and even rebooting the host node doesn't seem to work either.

 

[bitbud]

There is a known issue with some KVM based Windows Guests. I was able to resolve it with a simple change to the confoiguration file for the virtual.

- Make sure you are on the latest rev of Proxmox (1.3), which has KVM-86.
- In the web browser console for Proxmox, make a note of the KVM guest's VMID
- open a console (or SSH to) the Proxmox host
- edit the file /etc/qemu-server/<VMID>.conf where <VMID> is the VMID of the guest for example, nano /etc/qemu-server/103.conf

add the following line to the bottom:

args: -rtc-td-hack


This fix has worked wonders on all our Windows systems. We were expierencing clock-sync issues where the guest would slowly fall behind (a few seconds per minute). This also seemed to affect performance, as our Windows systems are much more responsive now. This was particularly effective on SMP (4 Proc) 64 bit systems.