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Affordable Home Backups for 10-100G Systems?
MichaelJames asks: "Ok, I have my MP3's streaming, all our digital pictures up, and a file server running on one machine in the basement. What would be the best way to do simple backups of the system and data? Get a tape drive Get a CDRW or DVDRW to backup the MP3 and pics, but use the old Zip drive for the file server data?" With drives in the 10-20 gig range only getting smaller and less expensive, what are we to do for backups, that have yet to scale well in the same range. For home systems with up to 100G of storage, what do you use to back up that much data, with a solution that's affordable to the average computer user? Have DVD writers become cheap enough for serious consideration as a backup media?
I have a 100BaseT network, and a server computer that resides in a different room from the rest of my systems. I rotate backups using those aluminum drive caddies. A pair of 60G drives turned out to be MUCH cheaper than the equivalent size tape backup. Every day, I rotate out the drive at the end of the day, and swap with the other. The spare I keep in a fireproof safe. Just tarball the appropriate directories. Done. Poof. Much faster than the average DDS3 tape drive too. Runs at night and I don't even notice it.
Onstream 30 or 50 GB ADR Tape backup.
Pros:
Can be found for under $100
Linux Support!
Cons:
Tapes are expensive
This will also work for laptops. I recently purchased an external drive enclosure with a PCMCIA connector (also available in Firewire and USB), and a separate 3.5" hard drive. The cost of the two together was less than these external drives they advertise for backing up your notebook, plus I can reuse the drive enclosure for any 3.5" hard drive.
The drive enclosure was a bit more expensive than the rack mentioned above (under $100 with shipping) however it did come with a two sets of enclosures - one for the drive itself to use externally, and another to put in a PC cabinet if you want to hot swap the drive with it instead of using the card slot.
I'm not a journalist, but I play one on slashdot
Agreed that just backing up to another HD provides the best overall method for creating a complete backup of 100MB of disk storage.
However, I would suspect that most users don't change a huge percentage of their HD's content on a daily basis, unless you are routinely d/l'ing or ripping MP3s and MPGs on a daily basis (and I note that when I do generate that kind of traffic, it is usually because I am making a compilation CD, and while this does generate a few GB of "new" files on my HD that day, that data doesn't need to be backup up because I've got the original CDs anyway).
As a result, it seems to me that a reasonable solution is to create a "baseline" backup, say to a CD or DVD, at system install time, when there is (relatively) little on the disk, and then each day (or week, depending on needs), do an incremental backup of changed data only to another CD.
This approach is obviously quite inefficient if you have a complete HD failure, in that you have to recreate a new drive by starting with the first backup CD and then restore EACH ONE thereafter until the final CD restores the disk to it's last backed-up state, but for a more common problem of losing or corrupting an individual file, since that is more likely to happen with a recently modified than a remotely modified file, you are likely to be able to restore a last good version within only a few CD's of the most recent incremental backups.
A lot of people have mentioned that disk to disk backup seems to be the best way to go.
I agree.
What hasn't been mentioned is rsync, which makes disk to (local or remote) disk backups fast and easy.
It is trival to set up a second disk that is a "stale" mirror of your primary disk(s) that backs up nightly, and will boot off a floppy. This captures some of the advantage of RAID (quick recovery) while being an actual backup, not just fault tolerance.
Rsync can use ssh as a transport, so you can securely back up remote disks as well.
-Peter
RAID offers good protection for some things: hardware failure (ie: HD crash) and uptime. That aren't the only woes, however... You can loose data in a lot of ways:
Disaster (fire, quake, flood, nuff said)
Hardware failure (disk, controller, ...)
OS failure (FS corruption, ...)
Application failure (User space applications malbehaving, virii, ...)
User failure (accidental deletes, experimental children - trust me on this one ;-)
:)
...) are a plus, but more cumbersome.
RAID will protect you from the second, but will happily add nothing in case of any of the other failures. Backing up to another media is a necessity.
Adding an extra disk (or two, or three), and some tar/cpio cronjobs will add basic protection. (No disaster recovery for you, unless it's off-site
Removable harddrives (firewire, frames,
Tape is considered a more 'trustworthy' backup medium because the mechanism and data storage are separated (ie: tape drive / tape), while in a HD it's in one single package, and it's not as easy to replace the logic board/stepper motor if this flunks. With tape it's easier: just get a new tapedrive.
Anyhow: don't rely on RAID to save your data - it won't.
Okay... I'll do the stupid things first, then you shy people follow.
[Zappa]
There are two ways you can go relatively cheaply, and IMHO a far better solution than CD-R or CD-RW.
Pick up a DLT2000XT (15gb native) off ebay for about $200. Tapes are dirt cheap, about $5/ea and the media is extremely durable, nearly indestructible.
Pick up a DLT1 (40gb native) off ebay, about $500. Tapes are moderately expensive at around $20/ea, but again the media is extremely durable.
DLT is industrial strength backup, the drives are built like tanks and the tapes can take incredible abuse.
Its all standard SCSI and works great with linux, no problems whatsoever.
I considered buying hard drives for backups, but they are far too fragile for long term backup and off-site storage. Most drives arent designed to be spun up and down lots of times either.
Last thing you need is for your backup harddisk to go splat when youre trying to power it up to restore your main system from a data loss.
With DLT, this isnt likely to happen.
FYI, if there's anyone out there in retail sales working for a place that sells HP computers, you can log on to HP Info Lab and you can get a $400 rebate for the HP 100i DVD writer. There's also a $50 rebate available, which you can use in conjunction with the $400 rebate. The $50 rebate is available to the general public.
This brings the price of a DVD burner down to $150, since the drive is 600 coon skins before rebate. At that price, and if the playstation 2 drops in price this christmas, i sense lots of burned games in my future...
sig?
Since when is a harddrive not a semipermanent media that can be easily taken off site? I'm surprised this comment got modded up so high. And since when are tapes such a reliable media compared to a hard disk? So burn-in the drive for a few days before using it for backups. And use a S.M.A.R.T. utility to diagnose the drive before each backup to reduce the chance that something is getting ready to fail.
Your best option is to put all data on a 2-disk mirrored RAID and use another drive as a removable for an off-site or fire-safe backup. The probability of 3 hard disks failing simultaneously, one not in use, is so incredibly small it's laughable. And for that non-zero chance, if it happens, you can pay to have the spindle of one of the failed drives transferred to a new drive in a clean room.
This may not be the best way to do it, but it works for me...
I have a "backup" hard drive in my server. This drive is always unmounted so that there is no chance of filesystem corruption from the operating system.
I just use a crontab to run a simple script that mounts the drive and coppies whatever specified backup files to it, then unmounts it. The same method slightly modified could be used to back up this same backup disk to another location on the network on regular intervals.