I'm currently running a small to medium sized network consisting of approx. 40 workstations and 30 servers (both physical and virtual) consisting of various versions of Windows 2000, XP, 2003, and a single Thecus N5200 Pro. My current backup solution consists of Backup Exec 11D and an HP Storageworks DAT72 tape drive. Backups are done nightly and are currently at 54 GB although there is an additional 100 GB that I would like to add on to that job. The job is not incremental or differential, it is a straight backup of everything to a single tape. Wednesday's tape is taken off-site for 3 months after which it is returned and archived permanently. Thursdays tape is archived on-site for 3 months. Monday, Tuesday, and Friday's tapes are reused each week. Backups are not done Saturday or Sunday because employees have weekends off and very little changes occur during this time.
I would like to rebuild this backup solution in terms of more storage volume and less human intervention. These two items have led me to research HP's StorageWorks 1/8 G2 Tape Autoloader.
My question is: If we were to go with the G2 (using LTO-3 tapes initially), what changes would you make to my current backup solution? This could involve reducing the number of tapes ($$), incremental or differential backup job, ease of restoration, permanent storage, temporary off-site storage. The size of the backup job would start at 154 GB and would not exceed 400 GB for at least 3-4 years at the earliest.
If you have a solution that involves different technology/approach please feel free to post as I am interested in all possible solutions to this problem.
As I am sure you are aware -- incremental and differential backups are a trade off. You gain faster overall backups with less data on tape, however restorations are more complex and slower. Incremental backups have always struck me as "RAID 0 for backups" and I avoid them.
Tape/Nearline Hybrid
Based on your current use, I might suggest reviewing the benefits of a full backup to tape on a Monday (so the tape can still be archived for 3 months, and then permanently stored), and then each day doing an incremental to nearline storage. Since your M/Tu/Fri tapes are recycled and possibly dont leave the site -- replacing that with nearline disk storage could reduce the complexity considerably.
Cloud Backup
Based on your bandwidth, recovery requirements, and data change rate -- an online backup solution can be rather appealing. They typically do a one-time full backup, and then take incremental and compile them such that you can restore from a single point in time and you are none-the-wiser they were pulling incrementals the entire time.
Much as online backup may be tempting in your scenario, I would seriously urge you to fully research the viability of doing a full server restore from such a backup before making a decision about it. Also consider the times you need to make a one-off emergency full backup, e.g. before installing a new service pack.
The HP unit looks good, and while I don't have direct experience with their kit I have heard enough good things to satisfy me that you won't go too far wrong with it.
I'm fond of Overland kit myself, and while they're not really aimed at your level, something like their new ArcVault 12 might be an alternative option worth considering: http://www.overlandstorage.com/US/products/arcvault12.html
Now, about your strategy. If time windows, tape space and tape budget allow it, you could just do a full every night. It simplifies the whole setup for you, as you can restore from a single backup set without any fooling around. If you can't do this (and I'll assume it's not feasible), go for a nightly differential so that you have a max of 2 backup sets (last full and last diff) to go back to. Never go incremental, it's just too much hassle.
With LTO3 and differentials you can aim for one tape per week. So configure your weekly full to overwrite and your nights diffs to append, set an overwrite protection of however long you want to keep data for, and do the calculations from there. Using a proper tape library like the Overland can automate the whole thing for you, which is very nice.
Above all, my usual advice on backups to keep it simple and boring, avoid exotic seeming solutions, and try to retain some manual element in it applies also.
A small tape autoloader like the HP ones you've looked at is probably the simplest route you could go down.
Otherwise, have a look at the Barracuda Networks Backup Server. At around $1000 for a 1TB device, you simply back up to it as if it was a file share, then it copies all the data off-site in the background, and you're charged $50 per 100GB per month of off-site storage used.
It's very simple and effective, but over 3 years the cost does add up.
Ewan