From the forums:

Q: I have setup some templates for Virtual Machines and would like to know how long it should take to make copies of these templates for use. We have an iSCSI San on its own network as well as a dedicated managment network and it can take 30 minutes to copy a template or make a copy of a virtual disk of 30GB.

A: Clones on your storage server should take only a few minutes... faster if you use thin provisioning. Likewise, clones using Virtual Iron take a few minutes (use the clone feature in the virtual storage tab) when you're cloning on the same array. Of course, if you're cloning across arrays, you have to use the fabric (FC or iSCSI) and the time depends on a lot of factors, such as bandwidth and latencies.

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