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The "Not Quite Amiga but still computer related category" => Alternative Operating Systems => Topic started by: mgerics on December 10, 2007, 05:42:49 PM

Title: Advice Requested
Post by: mgerics on December 10, 2007, 05:42:49 PM
Using Sony Tape Drives with Veritas BackupExec 8.6 on three different M$ nt/2k servers.

One drive already died, another appears to be failing, and the tapes are old enough to start failing.

So, I am concidering a SAN, NAS, etc. one of those neat networkable-plugitinandllyourworriesareover devices.

Anyone have a USEFUL suggestion which to concider, or should I concider one at all?

Thanks

Title: Re: Advice Requested
Post by: rkauer on December 10, 2007, 06:14:07 PM
 Consider a cross-backup over the network is the best bet... :roll:
Title: Re: Advice Requested
Post by: motorollin on December 10, 2007, 06:23:22 PM
Try to get one with RAID - at least mirrored, ideally striping with parity. That way your SAN isn't a single point of failure - if one of the disks goes down, you can rebuild the array from the remaining disks. For true redundancy you should have two of these, in case the whole array goes down (e.g. power surge kills all of the disks). Iomega and Buffalo all do SAN drives with built-in RAID (i.e. they contain multiple physical disks which are exposed as a single share).

--
moto
Title: Re: Advice Requested
Post by: ChrisH on December 10, 2007, 06:40:50 PM
BEWARE:  Using a RAID with a NAS/etc makes your *NAS* a potential single-point failure!

As most devices implement RAID in different ways, if you NAS dies you will likely be unable to read the data on your RAID HDs.

The solutions are:
1. Buy an identical backup NAS , or
2. Don't use RAID, but simply use a traditional backup system, possibly in combination with a (non-RAID) NAS...
Title: Re: Advice Requested
Post by: Hans_ on December 10, 2007, 06:58:20 PM
@ChrisH

The Buffalo NAS devices are essentially Linux machines, so I'd assume that their terastation HDs could be taken out and connected to a RAID controller in a standard PC if the device failed. You'd have to ask someone that actually has one of those devices if it's true though.

It's a real pain that they don't implement it the same way.

Hans
Title: Re: Advice Requested
Post by: Tahoe on December 10, 2007, 07:31:47 PM
Don't confuse SAN with NAS. A SAN is generally fully fibre channel SCSI using fibre channel switches, I don't know what amount of data you are talking about, but the growth should be pretty hefty if you want to consider SAN. (you can later on add cheap SATA disk cabinets, but we are talking pretty hefty storage here, we just bought a new SAN at work with is now "just" 8TB, but can grow to 173TB, servicing 128 servers.
A SAN is by standard fault taulerant, runs RAID 5 including hot spares. All fibre switches/interface cards are redundant (dual).

NAS is nice and all, but I would still go for DAS (Direct-Attached-Storage) if a SAN is out of your league.
Title: Re: Advice Requested
Post by: Tahoe on December 10, 2007, 07:32:44 PM
Quote

motorollin wrote:
Try to get one with RAID - at least mirrored, ideally striping with parity. That way your SAN isn't a single point of failure - if one of the disks goes down, you can rebuild the array from the remaining disks. For true redundancy you should have two of these, in case the whole array goes down (e.g. power surge kills all of the disks). Iomega and Buffalo all do SAN drives with built-in RAID (i.e. they contain multiple physical disks which are exposed as a single share).

--
moto


Those are NAS, not SAN... :)
Title: Re: Advice Requested
Post by: Hans_ on December 10, 2007, 08:15:37 PM
@Tahoe

Actually, ethernet SAN devices do exist. IIRC, they use the iSCSI protocol.

Hans
Title: Re: Advice Requested
Post by: Ilwrath on December 10, 2007, 08:21:57 PM
Quote
Anyone have a USEFUL suggestion which to concider, or should I concider one at all?


I guess it depends on what you are wanting to do.  SAN or NAS are really for online, on demand file serving.  If that's what you want, then go for it.  There are plenty of reviews of various devices out there.

If you just want a backup solution to replace the failing tapes and tape drives, though....  It's darn hard to beat a large hard drive in a USB or SATA case right now.  Heck, they're cheap.  Buy two.  Keep one on-site for the dailies, and take one home or to the safety deposit box for the weeklies/monthlies.
Title: Re: Advice Requested
Post by: Tahoe on December 10, 2007, 08:23:05 PM
Quote

Hans_ wrote:
Actually, ethernet SAN devices do exist. IIRC, they use the iSCSI protocol.


I know, but there is no comparing a SAN to a NAS, not on specifications, not on pricing. Even iSCSI SAN's are much, much more expensive then NAS'.
The EMC SAN we run at work has both Fibre and iSCSI, there are models which run Fibre only or iSCSI only.

Reading the orginals poster's question though I figure he is using 3 servers, forget about SAN, it is not, and will never be cost effective even when compared to DAS.
Title: Re: Advice Requested
Post by: ChrisH on December 12, 2007, 05:11:16 PM
@Hans
Different mobos implement RAID in incompatible ways, presumably due to different chipsets.

So you *might* be able to find a compatible RAID implementation, if you NAS/*etc* dies, but I wouldn't count on it for my precious data...


This isn't a problem for big server providers (that RAID was originally designed for), because they have a rooms full of identical servers.
Title: Re: Advice Requested
Post by: mgerics on December 12, 2007, 06:01:18 PM
Found something called FreeNAS - linux based system that supports RAID - It can boot from USB or floppy. Looks promising! I think I am going to give it a try:

http://www.freenas.org/