I have a couple of Asp.Net web apps running a Windows Server 2008 R2 VPS. We have been using this VPS for years. Since the last few months, we have had our apps go down for 30-45 mins. This doesn't happen periodically and this doesn't happen at the same time of day. This must have happened maybe 4 or 5 times in last 2 months. Our analytics dom't report a large numbers of users simultaneously online. We have had more users online and have had no issues.
During the downtime time, we cannot RDP into the VPS. New relic monitoring shows zero activity on any front. After the VPS is back online, the apps work normally. Even after the VPS is back online, nwe relic doesn't show any new entries for that time period. The event viewer also shows no entries during the downtime period. We have the usual entries in the System/Security/Application logs, almost one per minute, till the time the downtime began. And the next entry starts after the downtime was over.
It looks almost as if for that duration, our VPS was put to sleep. I have checked the event viewer for events with ids 6005,6008,6009,6013,1072,1074,1076. I read in various internet posts that these event ids can help identify planned/unexpected shutdowns/restarts. I didn't find any for this time range.
What else can I do to identify why this is happening and to prevent it from happening.
EDIT
This instance of the downtime was due to the host rebooting the physical server. Wrt to the previous downtimes, the host claims to have not been involved. Lets see. I am currently marking @Greg's post as the accepted answer, as that was something I had not considered doing till now.