I have several coLinux running in different Windows hosts. Occasionally, the time in coLinux advances by several hours and up to a day! The time on the Windows hosts always remains correct. This happened on multiple coLinux servers, some of them ran NTP, but it seems that NTP will not adjust clock if the offset is too large. It also happened on a server that did not run NTP.
It should be noted that that the the large offset of 9 hours or more happened at once. It's not a small offset that accumulates.
How can this happen? Can anyone explain how time is kept in coLinux? I know that vmWare and HyperV have special tools for keeping the VM clock in sync. Is there anything similar in coLinux? What are the recommendations for keeping time in coLinux?