I have two linked virtual servers running Windows Server 2012:
- A database server with Microsoft SQL Server Express
- An applications server running Tomcat and a relatively lightweight application.
Both servers are 4GB.
They both mysteriously restart with Event ID 41, without creating a MiniDump file. The restarts happens approximately once every two weeks and only happen at random times in the night. It is unusual for our users to be using the application at night, and the only fixed thing that happens at night is the Backup of the database at 5am, (and most restarts happen before this)
The cloud company opened an investigation and couldn't find anything amiss. They updated the VMWare. Their only suggestion is to increase resources of the servers.
They also claim that the problem cannot be the hardware, firstly because it is a cloud based system, and secondly because no other clients are complaining.
In Virtual Machine server restarts mysteriously a suggestion is made that the installation is corrupted. However I would suggest that this might not be a reason in our case. (1) for both servers to have the same problem would be a bit coincidental - unless of course they were both installed wrongly (2) it does not explain why the restart happens at night.
Any ideas?
UPDATE
- One server is not connected to the Internet, so DDOS issues are not relevant.
The crashes happen at completely random times, but always at night
I posted a sample System Events Log at http://textuploader.com/d9opz - nothing interesting happened before 2am. The crash happened at around 2:17 am.
I do not know of any particular scheduled tasks that happen at night.
Moving the VM's around is not an option at the moment, although here is a little bit more information: They are running on VMWARE, and are virtual servers running on separate VLAN's.
We have a virtual test server which runs both the application server and the DB server (and has a very similar setup) which does not seem to have any problems.