Recommended size of VM LUN Volume

[pstokes1127]

We were told to build 200 to 300 GB LUNs to present to the vCenter Storage for our VM servers.  Each LUN has between 4 and 5 VMs on each one.  Because of the way we built it, we don't have a lot of free space on each volume.  We are finding this has hurt us when we try to use VEEAM and other backup software to back up our VMs.

What is the recommend volume size of a LUN for VM?  And how much free space should you have available after loading the indivdual VMs on this LUN?  For example, if we have a 300 GB LUN, do we need to leave 150 GB of free space for backups and snap shots?

Thanks for your responses to this.

[DSTAVERT]

As always the best answer to questions like this is "it depends".  Here is a document that might be useful. http://communities.vmware.com/docs/DOC-10990

[patrickds]

A minimum of 20% free space is recommended.

But it also depends on how busy your VMs are during the backup (how much data is written), which will determine the size of the snapshots.

When backing up multiple VMs on the same datastore at the same time, you'll have to provide enough free space for all the snapshots.