Comment Re:To Tape... (Score 4, Insightful) 403
The thing is though, tape *sucks*.
The most common reason for needing a restore, is accidental deletion. With modern backup-systems using online disc, the user can in this case simple open his backup-client, find the file, and click "restore" - time elapsed 2 minutes, help needed, none.
Tape means talking to IT, and wait for hours, at significant personnel-cost. Unless there's a fancy automatic tape-switching-robot kind of deal, but if there is, the price is no longer $30/TB.
Yes you need off-site-backup in addition, and it's acceptable for that one, to have higher latency, so perhaps tape is okay for that.
What you describe sounds like a tape-per-server solution, but anyone using virtualization or even having a reasonable size will use an enterprise backup solution that's user friendly regardless if the back end is disk, tape, or both. We use TSM to tape libraries of Ultrium5 drives (and disk pools for a backup landing place/1st day restore). Need to restore files or directories? Open up the local web client, click what you want in the GUI (and potentially a point in time you want to restore it from), and it's automagically done in 1-2 minutes. Regardless if ti's last night's backup or something from 3 years ago. Most of that time is the robot loading the tape(s) and seek time - getting data off the tapes is fast.
We back up about 5TB of changes daily, and reclaim about 3.5TB of old no-longer needed data daily (much needs to be kept for extended periods for compliance issues), with over 2PB in-use storage. Power/cooling costs for tape barely move the needle, that much disk would have a large impact on our datacenters even using deduplication.
Also, we have both on-site (for speed of restore) and off-site copies of everything. Easy to do, the tapes backed up at night make copies automatically during the day. This isn't a replacement for disk replication to alternate sites for site disaster, it's for normal restores and keeping everything we need for compliance reasons safe.
I'm not saying disk is bad - disk is good. But tape is good too, and it's a different tool - fits a different niche than disk. Hammer and screwdriver will let you tackle more jobs then either one by itself.