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|Lower storage costs with snapshots|
Organizations typically initiate snapshots for reasons other than end-user file recovery, often as part of a disaster recovery or high-availability strategy. But once you have snapshot capabilities--which may come as part of the disk array or sold separately by a third-party software company--users can easily access the snapshot or make an extra snapshot just for themselves.
Southern Adventist University in Chattanooga, TN, uses a BlueArc Corp. network-attached storage (NAS) appliance to store files for its School of Visual Arts and Design. BlueArc includes snapshot capabilities at no extra charge with its arrays, as do many NAS vendors. Now, the school is planning to add low-cost ATA disk drives to allow students to restore files on their own (see "Lower storage costs with snapshots").
"We'll create a hidden folder using the tilde (~) and put all the snapshots in this folder. Students who need to restore files can go to that folder and just do it themselves instead of coming to us," explains William Cordis, IT administrator for the university's School of Visual Arts and Design.
End-user file recovery won't save Cordis much time--"it only takes me two minutes to restore a file from a snapshot." But it will save the students a lot of time. "For students, it's a big hassle. They have to run around and find an IT person and then describe the file," he adds.
Snapshots for everyone
The payback from end-user file recovery can be attractive. In an online storage forum discussion on the topic, one participant reported: "We use NetApp's snapshots all the time. Probably 80% of the user base knows how to use it and regularly does. Our operations guys have said that this takes care of about 60% of restore requests for data on filers."
Mainframe Entertainment, a Vancouver, BC-based video animation house, is slowly stepping into end-user file recovery. "I'm letting a few do it on a one-off basis," says Wendi Davies, manager of information technologies. The company uses pricey Fibre Channel disk for its primary storage and low-cost ATA disk for its snapshots, and puts strict limits on the amount of primary storage it allows its video engineers. But Davies is concerned that the company's engineers may intentionally delete valuable files just to gain some extra primary space, assuming they can simply retrieve the deleted files later from the snapshot. So for now, she's limiting this capability to a case-by-case basis.
Some managers don't like the concept at all. "I won't allow end-user file recovery," says David Weaver, manager of operations at Jefferson County Public Schools, Louisville, KY. "Users don't always know what they need, so they'll go look around in the logs. I don't like that. I'd rather they come to me if they have a problem."
This was first published in August 2004