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Best eSATA JBOD?
redlandmover writes "I already have an HP Media Server (upgraded processor, and memory) that has already been upgraded internally to 3.5TB. I'm sure everyone already has their favorite backup solution (RAID, WHS, a billion external hard drives, etc). My question is: what is the best JBOD (Just a Bunch of Drives), eSATA-connected, external hard drive enclosure? (Preferably, at least 4 drives.)"
This isn't quite what you want, but I have a $30 6 drive caddy (with 4 drives atm) and a $70 4 port internal SATA card. I just run long SATA cables to it, but it was cheaper than any single-cable solution i found, so that may not be a bad way to go.
One thing I noticed though was that I actually have enough room for all 9 of my hard drives inside my case! I may migrate them in.
And yes, before you say it, that is certainly quite a bit of porn!
-Taylor
Worldwide Military budgets: $2100 billion. Worldwide Space Exploration budgets: $38 billion. Really, world? Really?
Duct tape the drives together, then use software RAID JBOD.
That's what MacGyver would have done.
RAID 1 + swapping out/rebuilding a mirror disk periodically is a perfectly reasonable backup solution.
"I bless every day that I continue to live, for every day is pure profit."
Wow, that's definitely some iFail.
Mod me down, my New Earth Global Warmingist friends!
Duct tape the drives together, then use software RAID JBOD. That's what MacGyver would have done.
Duct tape? Oh heavens no! No, here's what I did: I went down to the local thrift store and bought a few big shelf speakers for ten dollars. Then I took them apart and got the really powerful magnets out. Using these, you can attach the drives to the outside of your case. There's one gotcha though--some cases are aluminum which means you have to attach the magnets and drives to your CRT if you have one. This usually just means a longer cable though.
The smart thing about this is that the drives are on the outside of the case so they remain cooler than they would in any enclosure.
If you think a RAID is a backup, you'll be overjoyed with the results of my advice!
My work here is dung.
...I can't get the manufacturer to acknowledge or confirm that there is problem when copying between hard drives in the same enclosure. Windows hangs and eventually the Event Logs show "device is not connected" or some sort of issue. Copying between drive and the motherboard's SATA drives works fine but it always hangs/times-out/becomes inaccessible after a random amount of transfer. It's surprisingly well put-together without looking tacky and well-priced but this copying issue between drives inside it is a pain. Transfer between drives inside it seem to work without a hitch using slower USB. http://mediasonicinc.com/store/product_info.php?products_id=150 It syncs with your PC's power so if the PC goes off, the box goes to sleep and wakes up when the PC power is restored.
You're better off with an SAS external enclosure and a SAS card with external connections. These can be expensive, but will pay for themselves quickly with the lack of extra management.
What management ? You get an eSATA chassis with a port multiplier, slot in some drives, and run a single cable to the eSATA port on the computer. "Management" doesn't even come into it.
It's a home media server. In what was is SAS even remotely justified ?
You do know that a RAID can be used for STORING backups don't you? Making your primary storage a RAID is no substitute for a backup. Adding an offline RAID storage can be a backup.
Until your controller goes berserk and craps all over your disk or your other disk fails in the middle of the rebuild. Or...
You can get an external (4-port, but acts like one big 1.2 GiByte/s pipe) SAS RAID card for less than $500 that will allow you to make multiple RAID sets of up to 32-disks in a set using true hardware RAID 5,6,10, etc. You can even get a battery backup unit for the RAID card cache for $100 (priceless on critical DB systems).
An external SAS card allows you to connect over a hundred drives through one connection using SAS expanders (some cards support up to 256 devices). Some external SAS RAID/JBOD cards have two SFF-8088 connections, for eight SAS lanes total. That's 2.4 Gigabytes/sec raw. At that rate, it's your PCI-e bus that's usually the bottleneck.
A lot of SAS expanders are expensive, but Chenbro has some ones for $300 that spread one x4 lane SAS cable into 24 or 32 cables, plus they can be daisy-chained for more storage. Then, buy a nice 24-slot Supermicro 4U chassis with dual-redundant power. That's a little less than $1000. All you need is the Chenbro expander in the chassis, no need for a motherboard.
If you're really cheap, you can use a cheaper $150 external SAS JBOD-only card, but hardware raid really is a must if you have a lot of storage. Plus, a hardware raid can use write-back cache, since it has effectively non-volatile RAM using the battery backup unit. And no, a UPS is NOT a replacement for NVRAM... Has your system ever crashed for any reason or hung for any reason? I've never had a RAID card hang or crash.
So, basically, besides the external SAS card, you have:
24-slot chassis with redundant power: $1000
chenbro SAS expander: $300
cables: depends
That's about $60/slot, plus you have redundant power (and an upgrade route to dual-redundant controllers). You can scale this to hundreds of terabytes, too. Over a petabyte if you have multiple controllers (with raid array rebuilding on one card not affecting rebuilding on another).
Except when your backup server uses RAID...
"When life gives you lemons, don't make lemonade. Make life take the lemons back!" -- Cave Johnson
yeah sure.
Let's say it again: Backups are:
- off-site
- offline
- multiple
- tested
anything else is just some kind of high-availability solution, that does NOT protect against catastrophic failure, fires, viruses...
The Cloud - because you don't care if your apps and data are up in the air.
The Rosewill RSV-S8 is pretty much exactly what you've described. It's an eSATA enclosure with 8 drive caddies, a power supply, and a fan. It presents the drives to the system as JBOD or one of the various common versions of RAID (implemented in software, I assume). Ignore the comically inflated MSRP; it's $300 on Newegg. It ships with its own eSATA card for compatibility purposes, but I assume it would work with any eSATA adapter that followed the proper specifications. There's also a five drive version available for about $100 less, give or take. I can't speak to the reliability or ease of use, but this sounds like it will fit your requirements.
No that's not correct. JBOD is just that. Just a bunch of disks. Has nothing to do with redundancy (or lack of redundancy). What you do with them is completely up to you. You can implement a RAID-Z with them on solaris (which is actually faster on my Enterprise-class disk array than the built-in RAID-6 in hardware!), Linux RAID-5, RAID-10, or whatever. Except for issues of battery-backed caching, I have come to the opinion that for most low- to middle-end storage needs, a large JBOD and software RAID is the way to go.
Despite being at the forefront in almost all areas of number theory, Kummer was renowned for being very poor at elementary arithmetic. (A number theorist who was poor at arithmetic!) One story has him standing at the blackboard during a lecture, unable to compute 7 times 9. One mischievous student suggested 61, so Kummer wrote this on the board and started to continue. Another mischievous student shouted out that it was 69 not 61. At this, an exasperated Kummer, said "come on gentlemen, it can not be both". Later, it was rumoured that he told colleagues, he should have known the answer since it couldn't be 61 or 67, because 61 and 67 are primes and it couldn't be 65 because 65 is a multiple of 5, and he should have realized 69 was too large because 7 times 10 was only 70, so the only odd number left in the sixties was 63.
This post climbed Mt. Washington.
Talk about being old-fashioned. Sorry but you're wrong and all the disk-to-disk backup manufacturers would like to have a word with you.
In all seriousness I'm sure nobody believe you can't have a RAID off-site that is online running snapshots periodically. This protects you from fire, viruses, are equipment failure and at least in my case, allows for business continuity which is pretty important these days.
Of course I do go one further and backup to a 100TB library but thats largely because I don't want to maintain that much online capacity if I don't have to especially since I already had to purchase it once for my main SAN.
Use modern technology, you'll find it much more friendly. Most modern network storage strategies work out great. ZFS does snapshotting making it easy to deploy on small scales. Windows only? Well that's no problem either since you have Volume shadow copy and DFS based on whatever schedule you would like.
I go one further with DFS/VSC and use NetApp snapshotting on the back-end which mirrors the snapshot to another array at another building. Works out great and the only maintenance is the occasional swap out of hard drives when the RAID controllers preemptively fail the drive because they detect abnormalities that will lead to failure.
He NEEDS another computer on his network.
With only one computer/disk controller if one of them fails, all FS might end up toasted.
He also needs incremental backups, just overwriting a snapshot of you data is no good when you realize that you have just overwritten your data with corrupted data because your main computing is failing slowly.
Everything I write is lies, read between the lines.
Best method I have of backing up my data is simple. First equip/upgrade a few existing computers with 1TB disks even if you never plan to fill them up. They can be at your parents house, siblings house or work. Copy your really important data like work, projects, photos, music, video (movies, tv shows and p0rn don't count), basically anything that is irreplaceable. Copy that to a 1TB USB disk and copy all the data to the computers you equipped with the backup drives. Now you have your data spread out all over. You can use rsync over the net or via a USB disk to keep things updated between machines. You can even partition the large 1TB disks and make a separate partition for your data so it cannot be tampered with. If a machine fails then from any of the others you can replicate the data.
Sounds like a pain in the ass but I keep copies on my brothers PC and my work PC. Its only about 400GB total so its not even half of the 1TB disk which costs about 75 bucks, small price to pay for peace of mind. I have a big software raid 5 array for personal file serving needs but it is in no way shape or form a backup system. I once had my raid 5 go haywire because of some disk controller problems. After a hardware upgrade I almost lost the array but it came back up and had to rebuild itself. Thankfully it didn't send me into a panic because I had my most important and irreplaceable data backed up.
If you are rotating your swapped-out disks rather than continually using new blank ones, then the re-mirroring (if done vaguely intelligently) will only update based on the blocks that have changed since the last time that disk was running live in the array (i.e. an incremental update, which is much faster than re-mirroring from scratch).
"I bless every day that I continue to live, for every day is pure profit."
I disagree, since a single mistake (e.g. mistakenly reformatting the wrong device node, or physically losing the system while moving house) could still take out the whole kaboodle.
And for something you really care about, an offsite backup is worth it and not difficult. I uploaded my family photos to my ISP-provided online file space. If you want to make sure it stays private, encrypt before uploading.
You'll be crying when you rebuild that raid and two disks fail at the same time (happened to me). No - raid isn't a backup solution.
RAID 1 + swapping out/rebuilding a mirror disk periodically is a perfectly reasonable backup solution.
Sure, if you're retarded. I was going to say it was ok for home, but no, that's just stupid. Even a batch job that tars a bunch of directories onto a second HD works better (and no additional hardware either).
"We returned the General to El Salvador, or maybe Guatemala, it's difficult to tell from 10,000 feet"
Make sure to find a port multiplier with FBSS (FIS-based switching) support. Also make sure that your SATA controller supports this feature. Otherwise, there can only be one outstanding command for all attached disks, and performance will be abysmal.
after the cretin suggested that RAID was some sort of substitute for a backup.
Of course RAID is a substitute for backup. If you ever delete data, accidentally reformat, lose files to a corrupt file system, get infected with a virus, or have any other disaster of the sort, it's obviously something you did or should have anticipated. Thus, data loss is a sign you're inferior and a sinner and the gods of IT are punishing you. Accept their swift and painful lesson with whatever microscopic shred of decorum exists within that rotting, unused thing you call a brain and try to rise ever so slightly above the unenlightened mire of your life so it doesn't happen again.
Besides, it was probably all porn anyway.
Signed,
The cult of BOFH, flagellation division
The old AT cases had a power supply with a mechanical power switch, rather than a soft-switch like ATX power supplies. Old AT cases and power supplies should be just about free, just strip out the old motherboard and you have a decent, inexpensive solution. Like someone else said, just get long SATA cables, and run them directly to the drives. You can bundle them together with zip ties periodically down the length, or use wire loom if you want something a bit neater. You may need molex-to-SATA power adapters, but those are very cheap and reliable. If you pick the right case, it will have plenty of drive bays and cooling capacity.
Or, you can use one of those 4_3.5"_drives-in-3_5.25"_bays solutions if you need even more space and cooling capacity beyond what is already in your case. Even a small mid-tower case should support at least 6 drives using one of these.
Pick up a spare AT power supply while you are at it, and you will have a very reliable, well-cooled, very cheap solution.
RAID can be used to make two or more disks appear as one larger disk. It's nice when your backup disk is bigger than your primary disk.
OP asks questions about external eSATA enclosures, the entire first page of responses is an argument over whether RAID is backup... /....
Here's an ON-TOPIC RESPONSE! Horrors! Take away my EXCELLENT KARMA for this breach of /. protocol!
I have a client who needed backup for a lot of big video files. We bought an enclosure from PC Pitstop, eight bays each holding 750GB SATA hard drives (1TB wasn't really around last year when we got it) attached to two eSATA cards in the PC controlling the enclosure. We spent a month futzing around trying to get the enclosures to be seen. I forget who made the eSATA controller cards but they sucked - or the enclosure chips sucked.
So we turned to Burley, the guys who make enclosures for Macs mostly, but they work with PCs, too. These guys know their stuff. They told us not to use OEM hard drives in enclosures because some OEM drives you buy are dumped on the market and don't QUITE work with enclosures. They said use retail hard drives only. They also sell very good controller cards. The enclosure we got from them has worked fine for the last year and a half until last week when one of the drives went dead - no surprise. They aren't cheap, but they are well made and support is very good. I had both email and phone conversations with the Burley folks and they provide good support.
We also in the last couple months bought two MicroNet 4-drive eSATA enclosures with 1TB drives from Newegg for use on a Mac Pro. That was a huge mistake, since the drivers simply weren't seen by the Mac at all. Apparently MicroNet didn't bother to test the drivers when Mac OS X 10.5 came out and couldn't be bothered to provide support for that. So we attached the enclosures to a Windows PC and they work OK, although occasionally one or more of the drives will disappear and generate "drive not ready for access" messages in the Windows event logs.
Later, we decided to use those enclosures for iSCSI storage served up to the video lab. So I took one of the video lab PCs that were being replaced by iMacs and installed OpenFiler, the open source storage server run on Linux. The latest Rpath Linux kernel saw the drives and the enclosure no problem. I configured the iSCSI setup and everything seems to be working fine. And interestingly, none of the drives have gone offline like they did with Windows - which means it was Windows fault, not the drives. So now I can install an iSCSI client on the two iMacs - except Apple doesn't HAVE a Mac OS X iSCSI client, once again demonstrating how Apple isn't ready for the enterprise, since Linux has had them for years - fortunately there's a free Mac iSCSI client from another company - and serve up 1.8TB of iSCSI storage to each iMac.
So my advice is: choose your enclosures and the drives in them and the controller cards carefully. Take notice of what Silicon Image chipsets are involved, since SI pretty much dominates the market for those things and they're not the smartest tech company in the world. Make sure you get retail disks for use in the enclosures. Make sure you can return what you bought for refund or replacement because this stuff is not yet "set and forget".
Richard Steven Hack - This sig is TOO GODDAMN SHORT TO DO ANYTHING USEFUL WITH! MORONS!
A single disk is more risky than I would like. Especially since it's offline, it can fail without warning leaving me (unknowingly) without a backup and unable to update my backup until I get a new disk (and hopefully I didn't need any of the archival versions of any of the files)
A RAID is far less likely to suffer that problem. When a disk fails, I have a signal that I should replace enough disks to maintain the RAID even when the remaining old disks fail.
And, as tsalmark said, it's nice when the backup disk is bigger than the primary.
The grandparent obviously doesn't. ZFS is not in OS X Server 10.5, and was silently dropped from the advertised feature list of 10.6 after the WWDC.
That said, ZFS does go a long way towards working as a backup. With RAID-Z plus snapshots, you are safe from drive failure or accidental deletion. You are not, however, safe from attacks that compromise the OS (and are therefore able to write to the disk at the block level), or from things like theft of the NAS or having a power spike frying the controller and all of the drives. You can alleviate these by using zfs send / zfs receive to pipe incremental updates to a remote machine, however this still doesn't protect you from an attacker compromising both machines.
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No that's not correct. JBOD is just that. Just a bunch of disks. Has nothing to do with redundancy (or lack of redundancy).
This is incorrect. JBOD is similar to RAID 0 without striping, allowing one to use disks of dissimilar size. There are some RAID controllers that will incorrectly refer to presenting physical drives directly. However most RAID will correctly present a JBOD as a single logical volume.
Please refer to the Wikipedia article on RAID.