SmartCache is used for non-staged restore of files from vmdk files. As such, vms should be first copied to SmartCache and then to StoreOnce. What about if I want to restore files from VMs that are stored only on StoreOnce. Can I copy them to the SmartCache and then use non-staged restore?
- Andrej K
SmartCache devices are the fastest way of performing a Granular Recovery restore.
- With a SmartCache device the mount operation completes immediately.
- With non-SmartCache devices, the virtual machine disk is restored into a staging directory first.
You can copy from a non-SmartCache device into a SmartCache device, but you haven't really saved any time -- one way or another, you have just copied the data into an uncompressed folder.
Here's a relevant quote from Planning, Deploying and Installing Data Protector 9:
Backing up to a SmartCache device is very fast, as you would expect for a disk-based backup device. Unfortunately it does no compression or de-duplication so if you are backing up a 40 GB virtual machine, you will need 40 GB for the backup. So it is not really practical storage format for long-term archiving!
A typical VMware backup for an important virtual machine will use a SmartCache device as its destination. 1 to 2 days later there will be a copy job to put it into StoreOnce storage (while recycling the protection on the SmartCache storage). Perhaps at the weekend, or perhaps after a week or two there will be copy job to take it from StoreOnce and put it on tape.
Less important virtual machines - where it is okay to recover files in a few hours instead of instantly - would probably be backed up to StoreOnce initially, and then copied off to tape without ever using a SmartCache device.
Greg Baker is one of the world's leading experts on HP Data Protector. His consulting services are athttp://www.ifost.org.au/dataprotector. He has written numerous books (see http://www.ifost.org.au/books) on it, and on other topics. His other interests are startup management, applications of automated image and text analysis and niche software development.