Best Practice Backup LUN Size

[hetrickj]

I did several searches looking for best practices on setting up LUN size for backups. I have seen several posts were it appeared as if 2 TB LUN's were taking an excessive amount of time to backup. Can someone point me in the right direction or provide input on how they decided to size the LUN's for their backups?

Any info is much appreciated!
Thank you!

[Vitaliy S.]

Hello Janice,

I'm not sure I fully understand your question, but as far as I am aware there are no performance issues in setting up a 2 TB LUN size as a destination for the backups. The other question is that how are you going to present this LUN to the backup server? pRDM, vRDM, via iSCSI initiator from the guest OS?

Basically, answering my own question I would recommend using iSCSI initiator from guest OS as storing backups inside virtual disk or on VMFS will make them more difficult to access in case of disaster. That said, if you have an iSCSI connection from the backup server to the iSCSI target, then mounting NTFS LUN to Veeam server through software iSCSI initiator should be an easy task to do.

On top of that, here is a good blog post about pros and cons between RDMs and MS iSCSI Initiator:
Deciding between RDMs or the MS iSCSI Initiator

Thanks.

[hetrickj]

We have FC LUN's connected to our Veeam Backup server. I am sorry my question was not clear I was asking about LUN sizes. Basically I am looking for some feedback on what size LUN's people have associated to their Veeam to store the backups on. What did you gauge the size of the LUN on? Are you clumping a bunch of jobs into multiple large LUN's? Did you create LUN's the same size as your Datastore's and just go one to one?

[bc07]

We have our (physical) Veeam backup server also connected to FC SAN and use for the fileserver backup a 7.4TB LUN made of SATA drives as backup target. How much disk space you need depends on how big the full and incrementa backs are and fo how long you want to keep them on disk.
In our case for the fileserver the full backups are around 1.8TB (done monthly), incrementals are around 5-20GB a day, backup is set to keep 35 restore points that means we need space for 3 full backups and around 65 incremental backups = 5.7 - 6.7 TB.

[MarcelB]

On my site I have a blogposting titled Design Guidelines for Veeam Backup & Replication v5. Here you will find a calculation which can be used to determine the size of the backup storage. The calculation was taken from the forum.

http://up2v.wordpress.com/2011/03/01/de ... cation-v5/

[hetrickj]

Thank you for your feedback bc07 and MarcelB....I appreciate it! I will review your blogposting MarcelB thank you!!