MPIO log in SQL server everytime a snapshot is made

[jliu79]

I keep seeing these events every time a snapshot is made on Nimble for the SQL server:

Events ID 1:

\Device\MPIODisk### created.

And once in a while it will give me some warnings and errors like this:

A Single Path Fail-Over is being attempted on \Device\MPIODisk###

Microsoft DSM failed to return a Path to \Device\MPIODisk###

The device, \Device\Harddisk#\DR###, is not ready for access yet.

The SQL server is a Windows 2008 R2 VM on a Windows 2012 cluster. The version of the SQL server is SQL 2008 R2.

Everything seems to be working fine for the SQL server, but I just want to know what those events and warnings and errors are about. Thanks.

[aherbert23]

This is part of the synchronization process with VSS. When a snapshot is taken it is mounted to the server temporarily and VSS validates the snapshot. Once it is complete it's removed. That's why you're seeing a new device appear and then be disconnected. 

[jliu79]

Thanks Adam. Any idea what would cause those error messages?

[aherbert23 · Accepted solution]

Those will happen sometimes when the snapshot is disconnected from the host. It's a normal and expected occurrence.

[jliu79]

Ok, thanks again Adam.