Hard Drives as Backup Media?

rootus-rootus asks: "I funny thought struck me as I was going over the life expectancy for tape media for backups... Since the size of 3.5" hard disks is surpassing 100GB in a reasonably inexpensive package, has anyone thought of using them as backup media, as in a jukebox or autoloader? The access times and data transfer rate for data stored on them would make backing up databases, etc. MUCH more palatable (200+GB takes a LONG time to dump to tape for a full backup) Any thoughts on the matter?" Bet you've thought about this question before, haven't you? Has anyone done anything like this? If so, how well did it work?

Comments

Let me rephrase things

[The Mayor]

I'm reading some of the replies and thinking to myself that the /. readers don't understand what a backup system is.

A backup system is not simply redundancy (i.e. RAID). A backup system for files typically can recreate any version of a file requested by the user (as backed up according to the backup regimen). Thus, if you have nightly backups, you might keep every night for the past month, every month end, and every year end for a given document. RAID won't give you this.

I'm familiar with some expensive IBM products that do this. However, they're expensive. Basically, ADSM (ADSTAR Data Storage Manager, or something) is a product that allows regular backups of products, and access to every incremental version of the documents. On the backend, it can be hooked up to a huge disk cache and a robotic tape library. The end result is terabytes of near-online access data, with automatic versioning. Pretty nice. And if your disk cache was large enough, it would never hit the tapes. It seems to me that this could be modified to remove the tapes and present what the user requires.

I'm not aware of anything open source or free (as in beer) that does this. It would be really nice, though.

Hell, I've always dreamed about an automatic versioning filesystem. Documents would be automatically versioned. You could use CVS to handle this. Perhaps you could do something as simple as have some code executed upon every file close for files that are opened with write access. When these files are closed, they are added as new versions of the document within CVS.

When the disk reaches some capacity watermark, a disk cleanup agent would be invoked. Its goal would be to remove redundant versions of old binary files from CVS. Rules could be attached to the agent to perform tasks such as retaining specifc versions of binary files (i.e. retaining the first version, the latest version, and all versions from the last named version).

Users could tag specific versions of files. These versions would always be retained.

I know this would incur a significant performance hit for disk access. Perhaps I could limit such disk access to specific directories or mount points. In this manner, I could have a mount point for documents, all of which would be automatically versioned.

Plugins for Explorer could be built to allow users to tag versions of documents and retrieve specific old versions of files. I'm thinking something like TortoiseCVS, a beautiful piece of software. In fact, for prototyping, TortoiseCVS would be enough.

Now, is anything like that available? No? Perhaps I should do something about that.

Cheers.