How much Snapshot space is needed for a full backup?

[dominic1134]

Hello,
we are currently evaluating Veeam Backup and Replication 4 and want to perform Backups for the following Virtual Machines with the following disk usage:





Our VMFS Storages only have 155GB (VMFS_01) and 270GB (VMFS_02) of free space:





When we start a Veeam backup task of a virtual machine with 400GB Diskspace, can the temporarly snapshot which is used by Veeam be created anyways if there are only for example 155GB left on the VMFS Storage?
Where will the snapshots be created, on the VMFS Storage or directly on the storage of the esx hosts?


Thanks in advance!
Kind Regards

DS.

[rowdy]

Please have a look here:
http://vsphere-land.com/tips-tricks/how ... -grow.html

And here:
http://www.sentania.net/2008/11/vmware- ... datastore/

I hope this answers your questions.

[Gostev]

Snapshots take no space when first created, they are only growing with time as virtual disk changes (changed blocks are applied into the snapshot file). In case of backup, snapshot is present only while backup is performed, and then it is immediately deleted after the job completes. So you should not have any issues with disk space in your case.

[Gostev]

Rowdy you beat me by less than a minute thanks for the links!

[dominic1134]

Thanks alot,
now it's clear to me.

I have another question, does moving VM's via vmotion to another esx hosts cause problems with sheduled veeam backup tasks?

thanks in advance

[Gostev]

Not if you added vCenter to Veeam Backup (versus individual ESX hosts). But kindly please use forum's search before asking a question - most of the common beginners' questions have been already answered before in the past years

[dominic1134]

Sorry and thanks alot!

Kind Regards

[bpickell]

Ok, I have a question regarding this. I think we may have designed our VMWare network incorrectly. We currently keep separate datastores for different drives for a VM. For example lets say a VM has an OS drive, a data drive and a paging drive. We will create 3 datastores for this one vm. Hostname_OS_Vvol, Hostname_Data_Vvol, and Hostname_Paging_Vvol.

The problems that we are starting to see is that when Veeam backup is running is that these snapshot files are growing extremely large and are being stored under the OS datastore, which is quite a bit smaller in size than the data drive. So as a result the OS runs out of disk space and crashes.

Is there anything we can do to prevent these crashes? and also in order to be able to boot the OS volume the only thing we could do was to delete the snapshot files.. Are there anyway to get those snapshot files back. Apparently everything that was saved to the data drive yesterday is gone.

[Gostev]

You can change workingDir parameter in VMX file to have snapshot files created on different datastore with more space available. By default, they are created on the same datastore where VMX file for VM is located.

See here for more information:
Creating snapshots in a different location than default virtual machine directory

Thanks!