Adaptive Server database (Sybase) stops with a snapshot

[KBuchanan]

I have an "Adaptive Server database" (formerly Sybase) installed on a VM mounted on a VMFS filesytem(. Whenever I create a snapshot, the database services stop.

I get the following error:

An error was detected on device \Device\Harddisk1 during a paging operation.

I also get a Popup message:

*Application popup: Windows - Delayed Write Failed : Windows was unable to save all the data for the file E:\Apps\ECCoder\Interface\ADT\Production\RCVData\03-03-09. The data has been lost. This error may be caused by a failure of your computer hardware or network connection. Please try to save this file elsewhere. *

Any ideas? Is there some reason that I would get a Delayed Write Failed? This database has very little activity as based on perfmon monitoring. There is only 1-2 users that connect to the system and there is very little CPU demand.

Thanks for any suggestions!

[jbsengineer]

Assuming you are taking a snapshot without the memory you'll need to disable or uninstall the VMware Sync Driver. The sync driver will quiesce the drive and databases are not happy with this.

You can disable this in the device manager by "showing hidden devices" and disabling "sync driver" under the non-plug and play drivers. This requires a reboot.

[KBuchanan]

I am using these commands via RCLI to create and delete the snapshots:

perl vmware-cmd.pl -H <hostname> -U root -P <password> <path to vmx file> createsnapshot "Snapshot" "Nightly Snapshot" 1 1*+ perl vmkfstools.pl --server <host> --username root --password <password> -a lsilogic -d thin -i <path to vmdk file> <clone path> +*perl vmware-cmd.pl -H <hostname> -U root -P <password> <path to vmx file> removesnapshots

I don't believe the createsnapshot command is excluding the memory - do you? I hesitate to make the chagne you suggest ONLY because I have many other VMs that don't exhibit this problem. The VM that giving this error was cloned - just like the others were. That why this really annoying - I can't tell what is different about this machine other than it hosting the Sybase database.

[jbsengineer]

Either way(with or without memory) this should fix the problem you are seeing. I know when I had the similar problem it was sporadic. Could you try disabling the Sync Driver just to test it?

[KBuchanan]

Yes, but I'll have to wait until this evening after the users are off the system.

Thanks for the idea.

[KBuchanan]

We never did get this to work. I suspect that it may have had to do with slow (or no fast enough) connection to the NFS backup target (maybe??). The VM Guest locked up during the snapshot - for upto 5-6 minuties.

Currently, we ar running a licensed vSphere cluster and the backups are written to fiber-attached SAN. The snaps take about 20-30 seconds and VM Guest doesn't freeze at all. The bakcups comleted in <5-6 minutes compared to 20-30 minutes backing up to the NFS datastore.

In my case - fiber channel is WAY FASTER then NFS.

-Kevin