Volume snapshot services

We've come to depend on applications that can undo everything they do. In Microsoft Word, for example, you can reverse a series of edits by leaning on Control-Z, and you can restore them with Control-Y. But when you save the file, your undo stack evaporates and the last edit wins. If you accidentally delete the file, you might be out of luck because the Recycle Bin only works when applications (primarily Internet Explorer) use the Windows shell API. If you accidentally overwrite the file, you're almost certainly out of luck. Estimates of the cost of recovering from these kinds of incidents range from high to astronomical -- a revelation to no one, as we've all committed such blunders more than once. Though we might not call these incidents disasters, collectively that's what they add up to. [Full story at InfoWorld.com]

Note: I learned on Friday that Novell's forthcoming NetWare 6.5 will include the same volume snapshot feature discussed in this Windows Server 2003 story. I asked Novell's Rob Seely why this technology -- intensely desired by users -- is only now appearing in the mainstream file servers, although it has long been a feature of some specialized storage appliances. "Good question," Rob said.

I've also been mulling over a detail that turned up while researching this story. What Windows Server 2003 and NetWare 6.5 can do is snapshot a server volume, and enable users to recover previous versions of files on that volume. But what about your own local volumes? I was more than a little surprised to discover that Windows XP -- even the home edition -- has an early, and somewhat limited, version of the volume shadow copy technology that's rolling out with great fanfare in Server 2003. The Windows tips sites recommend leaving it disabled. This makes sense given that there is no "previous versions" client available to make use of the shadow copy service, but begs the question: why not? It would appear that Microsoft, and/or third-party utility vendors, could come up with an XP version of the "previous versions" shell extension that's used with Server 2003, and thus unlock the latent capability of XP's shadow copy service.


Former URL: http://weblog.infoworld.com/udell/2003/02/09.html#a601