We have a windows 2008 R2 domain with a physical domain controller server(HP DL380) acting as ntp role for the domain. This is setup to sync externally with 0.uk.pool.ntp.org, 1.uk.pool.ntp.org, 2.uk.pool.ntp.org, 3.uk.pool.ntp.org,
Recently the date and time jumped ahead just over 2 weeks causing various problems, mainly stopping users logging on and kicking existing users off the network. The only way I could fix the problem was by manually setting the time back and then running the command to test and auto update time sync which worked fine once the date/time was set back within the 2 week limit.
My concern is I still do not know what caused the date/time to change, I have checked event viewer etc and can see the date time changed gradually within a couple of hours.
I contacted ntp.pool.org and they confirmed no issues and also confirmed not heard of before so I am left puzzled and concerned that this could happen again at any time but more importantly i need to know what the root cause was.
any help appreciated, also I am aware similar issue can happen in virtual servers with host etc but my server is physical.