Non-provisioned space /= space available for volumes?

[Bobby Gillette]

Using one of our 4 clusters as an example, we have total space of 13723.56GB with 5125GB provisioned for volumes. An additional 5048GB is provisioned for snapshots, leaving 3550.50GB not provisioned.

We have roughly 1165GB taken up by remote copies, which would by my reckoning leave 2.4TB of storage (give or take) to create volumes. However, we would only be able to create a volume using full provisioning of 1.7TB.

Is there some sort of overhead with SAN/iQ that claims some of that space? Or could it possibly be that some of our volumes are set to thin provisioning while some are set to full.

Any help is appreciated!

[Mike Povall · Accepted solution]

Hi Bobby,

I don't think the space taken by remote copies comes into play here as I assume that the remote copy is in another cluster. As you have more than one NSM / VSA in your cluster volume creation will default to using two way replication so when you select new volume the front screen will show the maximum volume size using full provisioning as being half of the available space. Select the advanced tab and set the replication level to none and you will be able to fully provision the volume at the 3550.50GB that you have available.

Regards, Mike.

[Bobby Gillette]

Thank you Mike, that was exactly what I was looking for.

I did some light reading about SAN/iQ's replication options, and it seems that aside from bringing all our storage modules into a single cluster (at least those at the same software level), the two-way replication we have in place for our mission-critical volumes should suffice. I may kick around the idea of bringing them all into a single cluster and implementing three-way replication, but, if I understand the methodology correctly, it would require more storage than two-way does.

With the information you've provided I can improve the documentation I've been creating and also allow me to make a more informed recommendation to management.

Thanks again!