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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.)"
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.
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).
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.
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.
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.