What you're asking for is a redundant backup. A backup that has a backup is rather wasteful (redundant
).
haha yes, im thinking a redundant backup solution.
So my very simple solution now is: just have some drives attached to some computer that you either: manually mirror data (drag and drop, or use superduper to copy only stuff that's new), or use TM to backup the various computers. My rather useless/cobbled together system is just a set of 3 WD MyBook's (MediaBackup:1TB, Media:1TB, TM: 500GB) so my backups are arranged manually. If any one of those drives fail, you can see I still have all my data intact, without RAID. And much simpler.
Caveat: Time Machine backups have come to contain some data that is unique (ie deleted things in the 'past'), so losing the TM drive now involves actually losing stuff you only had a single copy of. Whereas normal backups are mirror images of a drive.
that is a very simple solution. better then my current one though - currently i only backup my computer to our (dead - long story) Time Capsule (which will hopefully be working once the capacitors arrive). i have another 2xtb + 2x500GB HDDs that are not backed up at all. nothing REALLY important on them
What say you?
Got some general idea of what I'm saying from here:
http://storagemojo.com/2007/05/30/home-raid-vs-backup/
thanks for the link. actually now that i think about it, i just found a PSU (from an old LaCie HDD) that i think will fit into my dual bay FW enclosure. it is JBOD and mirror capable. this would be a secure hardware RAID i take it.
the question is, mirrored or concatenated.
(sorry if that above is a mess. None of those sentences were typed out in order lol)
haha that made me laugh. thats aussie talk for you. not organised!
What?
I know the OS X page is confusing (gave me the impression it's only available with a RAID card), but it's been there in past versions, and from posts here on MR, is still in SL's Client Edition. You'll find it in Disk Utility.
the wiki page says OSX supports RAID5 software RAID. i guess its only with the appropriate computer/configuration though.
It will depend on the array you want to implement. You can do 0/1/JBOD with 3 ports. Type 5 if supported by the software, but again, NOT recommended.
what is the differences between RAID0 and JBOD? they both appear as one logical drive do they not?
EDIT: ahh i see, JBOD still had the read/write rate of one disc, RAID0 combines the read/write speeds. JBOD isnt a recognised RAID setup either. im guessing RAID0 writes data to drive one, then the next to drive two etc - where as JBOD just writes until one drive is full. also, i take it RAID0 capacity = the smallest size of the drive, JBOD combines them all together. i think i got it now haha.
You could use a SATA card if you need more ports, and use it's drivers to implement the software RAID.
It's the least expensive way to go, especially if you don't go crazy with it. And you won't have to worry about the EFI firmware support. Any BIOS based card will boot, but you will need OS X drivers for the card (or RAID card if you end up going that route).
SATA card, didnt think of that! they are cheap cheap cheap. nice suggestion
No, the speed wouldn't drop. Most green drives are able to pull ~77MB/s reads. So a type 10 would do 2x that, = 154MB/s. Even on the inner tracks, you should still be OK. Assuming you meant 80Mb/s (10MB/s), then it's well above that. 80MB/s, and you could have a problem hitting full speed. I figured on full 100Mb/s Ethernet, which is 12.5MB/s (below what a single drive can provide).
sorry, i meant 80MB/s, we have a gigabit switch and all computers support gigabit ethernet.
With 10, it's benefit is improved redundancy over type 5. It can lose 2x drives and still run, as type 5 is only capable of losing 1 drive while continuing to operate (you want to fix it during this time, or your data will end up gone). It's a trade off for the capacity.
good point. in a RAID10 situation you would be pretty unlucky to loose the two mirrored drives i guess.
But as it's a backup, you don't need to run this level on a home computer. You can always archive to an online source if you're paranoid (offsite being a better way to cover you from "Acts of God", such as flood, fire,...).
sorry, online isnt a viable solution. 25GB per month doesnt allow for that. (thanks Telstra)
The same as any single drive of that make/model, given the usage. Where this isn't so bad, is the drives won't be on most of the time (power management settings will shut them off, until accessed).
right so we are talking years then. thanks for clarifying
Just get a SATA card. As mentioned, you don't have to worry about the EFI firmware boot capability, as it's a hackintosh. You do need to get drivers for it though.
drivers may be hard, but then again it may be easy. it might even work OOTB!
PCIe or PCI (133MB/s), but it's fast enough for backup. The PCIe cards would be more expensive I think, but worth checking. Say a 4x lane card (typically has 4 ports). They're faster, and would allow you to change it to a primary location down the road if you want. Depends on your plans.
no room for PCIe as the GPU is in there, only got one port
No idea, as it doesn't say it has driveres for anything, let alone the chip it uses (i.e. Silicon Image provides OS X drivers you can get off thier site). Personally, I'd skip this one.
i think i shall skip it then
ok so after all of this i think there are four basic options i can go for:
1. use the hackintosh, 2x1TB, mirror the drives. only 1TB space
2. use the hackintosh, 2x1TB, JBOD the drives. 2TB space
3. use external dual bay fw400/fw800/usb enclosure, 2x1TB, mirror the drives. only 1TB space
4. use external dual bay fw400/fw800/usb enclosure, 2x1TB, JBOD. 2TB space
i think i am leaning towards option 4 a bit. the main reason being power consumption (no computer needed).
i should mention that IF our Time Capsule gets up and running again that it will be used to backup the computers as well - this makes option 2&4 even more considerable.
thanks to all for your input!
