I have a ESX Cluster setup running ESX 3.0.1. I just created a VM on one of the ESX server and have taken a snapshot after the initial configuration of the server. Now when i try to do a hot migration manually to see if the migration is smoother i started getting a warning something like below
"Reverting to snapshot would generate error(warnings) on the destination host"
VM has its disk on storage which is common to both the Hosts in the Cluster.
Not i am worried if the actual migration happens and at a later stage i might see issues using the snapshot taken now.
Also why its an issue as even the snapshot files are located in same directory as that of the VM and on the same filer.
Does anyone has any idea about how this works exactly and did any one successfully used above scenario??
You can ignore that message, the vMotion will still work fine, all that message means is that if you 'revert' to a snapshot on the VM after the vMotion you'll get some warnings in the logs. I've never had a problem with a VM with snapshots after migration and have done it loads of times.
You can hack a lot of what the snapshot does if you really get into it. You could have snapshots in multiple VMFS volumes referencing others on different volumes, that is how Lab Manager works.
Is there a way i can know more about snapshots..i mean PDFs, articles etc...we would like to use Snapshots as a backup solution but want to know more about the difficulties in it before we make a final call
Lab manager does a ton of other things. VMWare didn't engineer how lab manager does snapshots.
Although it's one of the main reasons they bought them.
I had one of the Lab manager specialist (from the origianl company) here a few weeks ago.
Eventually VMWare will incorporate their technology into ESX, but even VMWare agrees LM is FAR superior in it's snapshotting capabilities.
Also i have to migrate the VMs to a different VMFS
volume due to space contraints or some other reason
with the current VMFS i can't do this to a VM with
As of now the only way "Supported by VMWare" to move a snapshotted VM is it Apply all snapshots (so basically it's not snapshotted anymore) , then move it... Then start from scratch.
There are other ways to hack around doing it, but no supported ways, that was the official VMWare stance I got.
I had a whole thread going on about this.
You should not use snapshots as a backup solution to keep copies of VMs unless you are using them as a temporary means to get a quiesced VM that can be backed up to other media. VCB uses snapshots for this purpose but will commit the snapshot when it finishes the backup.
Snapshots are intended as a way to do test/dev, providing a way to revert back to a known good state. For example, take a snapshot before installing a new application so that if it fails to perform you can revert to before the install.
When using snapshots you should periodically commit their changes to their parent or delete them if appropriate.
You can find more information about snapshots in the VMware Infrastructure 3 Online Library at http://pubs.vmware.com/vi301