Advice for a NAS setup?

Portal Home > Knowledgebase > Articles Database > Advice for a NAS setup?

Posted by emilfalcon, 07-10-2009, 04:18 AM
Hi, I am currently researching and evaluating Network Attached Storage systems and was wondering whether anyone out there has had previous experiences (good or bad) with any certain setup? I am particularly curious to know: 1- what kind of a performance hit I can expect when data is stored on a NAS and accessed via ethernet over iSCSI as opposed to regular SATA or SCSI. 2- what pre-built NAS system would you recommend for a system that requires about 8 TB of disk space for file data and needs to have 100% uptime? I've been looking at: http://www.thecus.com/products_over....nguage=english However I don't know what sort of limitations this hardware offers as far as simultaneous disk reads/writes go. If anybody were to have some recommendations on this matter or willing to share personal experiences I would be very interested in hearing them!
Posted by StevenG, 07-10-2009, 06:01 AM
What kind of media will be stored and how will it be accessed? Dell Equalogic boxes (P5000 for example) are good for pure iscsi and you can bond multiple interfaces together eg to create a 3-4 GB network (if you need it). If you are wanting a cluster file system, accessed by a few hosts, then NetAPP 2050 and above are great. Netapp do NFS very well - Netapps aren't that great for iscsi though. You could also look at something like an EMC CX4 and add disk as you need it. With the EMC stuff you can add different types of disk, to suit your needs, ie flash, SAS and SATA within the 1 unit, on multiple shelves. Good thing about having multiple types of disk, is that you can have archived files or backups on a large array of SATA disks and host your performance applications on the faster (and more expensive) mediums. Really depends on your long term goal, whether you are streaming media, how many files and usage, whether you need redundancy or pure performance raid levels and of course budget. Thing is to work out exactly what you need first.
Posted by emilfalcon, 07-10-2009, 04:17 PM
Thanks for your input Steve! The NAS we want to implement will mainly be used to store web server files and emails, with a large number of concurrent accesses. The web sites using this NAS vary in scope and size so I cannot label it under one specific type of usage. However I do not plan on serving the most latency-intensive apps (such as MySQL DBs) from this NAS at the moment (unless, of course, it IS something that I can do without a noticeable performance hit and without going broke). As far as actual storage within the NAS goes, I am looking at 4-8 TB storage using SATA HDDs in (ideally) a RAID 1+0 setup. I am also not sure what interfaces to opt for (iSCSI, fiber channel, infiniband). I took a look at Dell Equalogic solutions. Apparently the P5000 is no longer being offered and got replaced by the P6000 series. costs aren't listed so not sure what to expect; what price range are we looking at here?
Posted by StevenG, 07-10-2009, 06:20 PM
Last P5000 equalogic I got was about NZ$50K, with 6.4TB raw disk. You're right, that has been superceded now, the new unit should be about the same price I reckon. Of course you could always build your own box with lots of disk if performance isn't really critical, and budget is . Used Openfiler in the past, but I wouldn't recommend that.. I'd build my own standard linux box with whatever flavour you're most comfortable with and create the arrays and exports manually (open filer does give you a GUI) It sounds as though a small NetAPP filer with NFS might be all you need to get going, Iscsi I only really use for windows boxes, NFS does me fine with our mail system at work, and we've had 90 million + files on that, within 3TB 'ish. You can get second hand netapps from ebay.. but watch out for the additional support and software if you need more licenses.. cos as far as I know, netapp won't relicense a second hand unit to you. Last NetAPP 2050 I bought cost about NZ$65K with snapmirror and nfs licensing included. Unless you're streaming media, you will likely not need Fibre channel, and it's expensive to get going. You can easily bond multiple ethernet interfaces together to create a 4Gb network or use 10Gb if you really wanted, and use either Iscsi or NFS/Filer. Fibre channel has it's place, but probably not for what you are doing right now. Last edited by StevenG; 07-10-2009 at 06:25 PM.
Posted by PhilD, 07-10-2009, 06:23 PM
Might take a look at a Netgear ReadyNas http://www.readynas.com/ they have units capable of up to 24 TB storage. I have used a small one (1TB) from them for years without problems. Some models support load balancing and iSCSI
Posted by emilfalcon, 07-12-2009, 03:23 PM
Have you tested the Equalogic under heavier loads (ie 1000+ simultaneous users)? I have taken a look at some of the cheaper alternatives (2-3k$) ReadyNAS and the QNAP TS-809U-RP but all the docs seem to talk about 200-300 simultaneous users max. I take it these systems aren't geared for more intensive usage? Couldn't find any stats for the Equalogic but at 20k$ and up I am guessing this should in theory be able to handle a much higher load. Couldn't find any benchmarks to support this, though. Seems most tests are focused on measuring transfer rates for single users rather than for large groups of users.
Posted by SA-ChrisM, 07-12-2009, 03:52 PM
Just a side note, do *NOT* do this over NFS. You will learn to hate the NFS locking mechanism and loathe it as a whole. Same for MySQL, you should really just handle that local to your MySQL machine as that's something that can be pretty touchy to latency and other issues.
Posted by StevenG, 07-12-2009, 09:47 PM
You'll not have a problem with number of user connections on equalogic or netapp with 'user connections', compared to the office nas devices. And you'll have no problem with NFS with what you are doing as well.. but iscsi is fine if you don't really need a cluster file system.
Posted by lockbull, 07-13-2009, 10:11 PM
Another option I'd urge you to consider is ZFS on commodity hardware; this blog entry gives a nice high level overview (though it's for a 20TB storage server). http://www.stringliterals.com/?p=58 You could of course also consider Sun's hardware; sign up for their Startup Essentials program and you'll get access to some nice discounts.
Posted by SoftDux, 01-14-2011, 07:18 PM
So what would you use then, iSCSO or SMB? Both have their pro's and con's.
Posted by CityNick, 01-15-2011, 04:14 AM
I'm not sure what your use case is but; check out the DroboElite it's 5 grand but is a pretty nice SAN for SMBs. It's a iSCSI rather than a NAS. For NAS check out Thecus, Qnap, Netapp, and Openfiler (diy). And if your a home media user check out Unraid (diy).
Posted by AltruHost, 01-17-2011, 12:25 AM
Have you looked into FreeNAS? FreeNAS is based on FreeBSD and will allow you to make a high performance NAS out of an extra computer or obsolete hardware, plus it supports iSCSI.
Posted by SoftDux, 01-17-2011, 04:28 AM
The Drobo's are a bit disappointing, in that it occupies 3U rack space but only has 8 drive bays.I've find the Thecus devices todo the same job better as the Drobo's.
Posted by jlkinsel, 01-17-2011, 03:02 PM
Second this. I'm going to be building up a SAN for a cloud service I'm working on - for me the following sites were quite informativeL http://www.zfsbuild.com/ - good notes on building out a large zfs-based san http://www.nexentastor.org/ - zfs-based software san product - free up to 18tb of storage John
Posted by eming, 01-17-2011, 03:05 PM
you should take a look at starwind - we've got a lot of clients running it...performs really well. we've got a few clients on Nexenta (your link above), does a good job as well. Alternatively you can lease by the TB on established SAN service providers...I can suggest a few if you'd like me to (PM). D

Add to Favourites Print this Article