What he said :). The obvious advantage here is if you do go with unify and the performance isn't good enough, you can: 1) add more servers 2) switch to SAS drives in the existing servers They only hold 4 drives though... you'd be looking at 8 spindles total. If that bothers you, you could do the same thing with the PE2950 2U's... they hold 6 3.5" drives or 8 2.5" drives (which is fairly common for fast SAS gear). Honestly though, I think you might be pleasantly surprised by the performance of modern SAS equipment... 2 1950's like Ananth said might be just the ticket. I quick run-through on Dell's site puts me at right around $3,000/each for a 4-drive SAS RAID10 with the bells and whistles I like. Of course, without AFR adding servers doesn't help your redundancy or availability... you'll still have missing data when a node goes down. Jake On Fri, Nov 28, 2008 at 12:12 AM, Ananth <ananth@xxxxxxxxxxxxx> wrote: > I agree with Jake, the ideal option would be using two 1U servers, and in my > experience, the Dell 1950s perform admirably for your requirements. They > would come with a factory installed PERC card as an option, you could look > into that. You'd have the options of atleast RAID 0,1, 5 and 10 on those, > and can handle SATA and SAS drives. I guess the optimal solution would be > two 1 Unit rack servers, having 4 drives each. The advantage here is, if you > want to save on costs, you could use SATA drives. You could upgrade them to > SAS later, to improve performance. They fit into the same backplane, the > SATA drives just need an interposer board. (My personal recommendation is to > go for SAS right away). Also, if you need to upgrade your space at a later > stage on these servers, you can always add on storage with a JBOD / RBOD > when required (something like the MD1000). > Regards, > Ananth > > -----Original Message----- > From: Jake Maul <jakemaul@xxxxxxxxx> > To: Gluster Devel <gluster-devel@xxxxxxxxxx> > Subject: Re: Recommended hardware for a unify cluster? > Date: Thu, 27 Nov 2008 20:03:25 -0700 > > Given that you say you're only after ~215GB of disk space, I'm curious > as to why you're looking to have so many drives. 80GB and 120GB are > "tiny" by today's standards. I understand the idea of "more spindles > == more performance", but is there some reason that 4/6/8 larger 10k > or 15k rpm SAS drives won't do the job? Those would surely outperform > 7200rpm SATA drives, or even WD Raptors. Even if you decide to stick > with 7200rpm SATA drives, I'd do some research first- if you buy 80GB > drives, you're undoubtedly buying older models (nobody > designs/produces new drives that small)... newer drives are much > faster, even at the same spindle speed. http://storagereview.com/ is a > good reference here. > > Presuming that you've looked into 10k/15k SAS drives and have decided > the price isn't worth it... > > I can't speak for anyone else of course, but the idea of a Unify-only > setup kinda makes me itchy. I much prefer Unify+AFR. Others have no > problem with it though, so to each his own... I don't use RAID-0 > either :). > > In your case, since you're not looking at a large amount of storage, > why not just go for a 2 machine AFR solution? Load is automatically > balanced between the storage nodes, so you'd still get the performance > advantage of multiple servers, plus high availability > (http://www.gluster.org/docs/index.php/Understanding_AFR_Translator). > My stance on Unify has always been "for when you can't get enough > space in 1 machine cheaply". Everything short of Solid State is 250GB+ > now though, so this isn't a scenario I'd use Unify in. Again, this is > a personal viewpoint here- others may feel differently. > > I think I'd go with a single server solution or maybe a 2-system AFR > setup... more than that seems like overkill to me. I'd also want to > watch the output of "iostat -dkx 30" for a while on your current > production server, and make sure that the storage system really is a > problem (looking for high usage% or long "await" times), but > presumably you've already done something like this. For a single > server I'd be seriously looking at 10k/15k rpm SAS drives (RAID10 or > maybe RAID5, depending on writes). For a pair of servers, I'd still > want that of course but would also consider recent-vintage 7.2k/10k > SATA equipment with a good 3ware RAID card, or better yet, something > that can work with SATA or SAS drives, like (IIRC) a Dell PERC5 > controller. > > I'm partial to Dell equipment, and most of my experience is > rack-mount... I'd be looking at something like a PowerEdge 1950 or > similar. Those hold 4 drives... enough for a 2-server AFR w/ RAID-10 > in each. For more space, you could go with an external MD1000 storage > unit (15-16 bayes, IIRC), or a 2U server like a Dell 2950 - 6 bayes I > believe. > > Offtopic: For a maildir-style mail store I would definitely recommend > looking at filesystems other than ext2/3 ... personally, I'd probably > go with XFS. If you're not already doing this, you'll find that > performance with many files per directory (10,000+) is much better > than ext3. > > Good luck, > Jake > > On Thu, Nov 27, 2008 at 11:17 AM, Brandon Lamb <brandonlamb@xxxxxxxxx> > wrote: >> Hello, >> >> Im hoping someone(s) can recommend commodity hardware to use in a 2 >> and/or 3 server unify setup. >> >> I am discussing with our other admins about migrating from a >> monolithic 16 drive scsi (160 drives) nfs server to a 2 or 3 server >> glusterfs setup. Given the two options what would you use for 2 and 3 >> machines? >> >> Should I use something like >> >> (2) >> Quad core 9850 >> 8g ram >> 8 sata2 120g drives, raid10 >> >> or >> >> (3) >> Dual core 5600 >> 4/6g ram >> 8 sata2 80g drives, raid10 >> >> If you would recommend a 3 server setup I would probably want the >> cheaper hardware where possible. Im just not sure (from lack of >> experience) if there would be a benefit to having 3 machines, but >> lesser horsepower, than 2 machines. >> >> The use of this is a 215 gig maildir format mail store.Our current >> scsi setup is using 73 gig drives on a P4 3ghz, 4g ram. >> >> One of the questions asked by one of the admins was whether a two 8 >> drive raids would perform as well/better using glusterfs than a >> monolithic 16 drive raid. My thought was yes based on we would have >> two machines with lots of ram compared to a single cpu, and also >> double the bandwidth. Also the cost of buying two 8 drives machines is >> less than a single 16 drive machine. >> >> Anyone out there with previous experience with something like this >> that can point me in a direction? >> >> >> _______________________________________________ >> Gluster-devel mailing list >> Gluster-devel@xxxxxxxxxx >> http://lists.nongnu.org/mailman/listinfo/gluster-devel >> > > > _______________________________________________ > Gluster-devel mailing list > Gluster-devel@xxxxxxxxxx > http://lists.nongnu.org/mailman/listinfo/gluster-devel > > > _______________________________________________ > Gluster-devel mailing list > Gluster-devel@xxxxxxxxxx > http://lists.nongnu.org/mailman/listinfo/gluster-devel > >
