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mbell

This is honestly pretty scary. There are a lot of single points of failure in this solution.

1) Single Box

2) Single Location

3) Single 40TB RAID 6 Array on single RAID card with 22 Drives (assuming 24 2TB drives, 2 parity, 2 hot spare = 40TB)

4) Single bonded network link means single switch, no redundancy against switch / network device failure

Honestly this may have been cheap but your getting what your paying for: An unreliable backup solution.

Also: Norco? Really? I wouldn't be trusting anything they produce with your company's critical data. Supermicro isn't much more expensive all things considered.

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Warning, the sound of a broken record coming up...

> An unreliable backup solution.

Nope. RAID is not a backup solution. It provides redundancy so the array can survive an event like a device failure (and so the data survives as a consequence) without significant downtime for repair (with zero downtime if you have hot-swap hardware) but it does not, and is not intended to, protect the data from the huge list of other things that can affect it.

RAID is redundancy for reliability purporses, not backup purposes.

>Nope. RAID is not a backup solution.

OP isn't saying RAID is a backup solution. RAID is being used as a component within the backup solution (the server).

Ah, yes. Sorry.

My knee has been playing up and jerked a little there.

RAID is certainly a valuable part of many a more substantial backup solution.

Hot spares do not provide less downtime compared to a supported drive failure (ie. 2 disks on raid 6). they just reduce the mean time to repair. Handy if your disks are at a remote site or your dealing with very large arrays but likely a waste of spindles if your sitting next to your data all day.

Not hot spares (which you are right, don't reduce array repare downtime): hot swap (which can). If a hot spare gets used you still need to swap out the broken device (its replacement becoming a new hot spare).

Wether you are swapping out a replacement for an active drive or swapping out a dead drive with what will be a new hot spare (a drive that was previously the spare now being an active drive in teh array) whether you have hot-swap or not makes a difference. Without, you have to power down the array for a short time which in an environment that needs availability to be as high as possible could be an issue.

Sorry I misread your post. I just couldn't fathom a storage solution without hot swappable drives.

4) Single bonded network link means single switch, no redundancy against switch / network device failure

Maybe, but not necessarily. Could be a pair of stacked switches (making one logical switch), with the bonded link having one port on each physical switch.

Good point. However, given the lack of redundancy elsewhere, and the fact that a pair of such switches could approach the cost of this server, I'd be willing to bet that this isn't the case.

S3 is more expensive than cheap storage, but S3 provides a level of data protection that you'd have a hard time duplicating at any cost.

In this case they already have a CDN which keeps 1 or more copy's of their data already and they just want a backup which makes S3 cost prohibitive. (You can save significant cash by using a service which gives much lower bandwidth access to that backup data.)

PS: Honestly, if their custom solution only add's one 9 of redundancy that may be fine. Their CDN is probably at 98+% up time or so which bumps them into the 99.8+ range which is better than most services out there.

I can't find any documented evidence of data loss on S3. Can you?

S3 has lost data 3 times in its history.

Documented evidence. eg not http://www.quora.com/Has-Amazon-S3-ever-lost-data-permanentl... "All of this is my recollection of what I've been told friends, so it may not be accurate at all."

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