Posts tagged qnap

Storage & Backup again

Seems like there’s a raft of people I know who recently lost some stuff due to disk crashes or are looking at ways to store that ever growing pile/stack/stash/gigabytes/terabytes/petabytes of data that people nowadays are generating. Even non-photographer friends I have are either busy downloading TV series or accumulating lots of media here and there such as e-books, songs, photos of their children, etc. Generally, media is usually the biggest culprit. I mean how large can a collection of excel spreadsheets or word documents be?

My approach is a two-tier storage system with my QNAP NAS playing primary on-line storage and a custom-built machine serving as the full storage backup. The following is a simple sketch of my network with my QNAP and my storage server. They’re connected to my Cisco switch using Link Aggregation (802.3ad) which offers both redundancy and faster transfer speeds. The little diagram on the right is how my content is stored between the server and the NAS. In a nutshell, my main storage server contains everything but the NAS has a little sub-set of the data.

Basically, my server stores everything in 1TB & 1.5TB disks, mirrored of course. I use rsync/robocopy to mirror as I’ve mentioned much earlier about using cheaper RAID cards. The mirrored pair is exposed on the network with one disk primarily for reading and the other for writing. What basically happens is that I back up to my NAS and my Storage Server (when it’s switched on – which is like at least a few times a week), pulls the backup from the NAS. When working on photos (especially for paid clients), I usually back-up simultaneously to both my QNAP and my Storage server. You can see below where I have my disks…

In case you are wondering (which you will), my disks are all short-stroked. My two swap disks are 150Gb 10,000rpm Raptor disks. Also, if you noticed, my storage server seems rather short of space… well, that’s because all the files are using NTFS junction points since I don’t have a RAID array… there’s actually 3 sets of mirrored disks. Total capacity is 1TBx 2 and 1.5TB x 4 / 2 due to the mirror. Usable capacity is about 3.4TB. Using junction points, 2001 and 2002 directories can reside on Pair A while 2003 and 2004 can be actually on Pair B. A bit complex but cost wise, all you need is a system with more than 4 SATA ports and you’re set. Recovery is also easier. Currently, the Samsung HD154UI 5,400rpm 1.5TB disks are good value but I’ll be moving away from them considering their slow-as-snail spin-up time and generally overall poor performance. I’m testing Hitachi’s affordable (runs a little hot though) 2TB, 5-platter, 7K2000 drive and see if it’ll give me back some performance lost to the Samsungs. Green drives may consume less power but the slow speed may result in high power consumption if we end up leaving more systems on just to complete back-ups and disks synchronization.

So far, I’ve been satisfied with my Seagate 7200.12 1TBs but looking for 1.5TB and 2TB drives are tough if you’re trying to avoid the green marketing crap.

NAS Purchasing Questions

Seems like after posting the NAS entries, I got a question from a friend trying to archive his photos as well as other data, i.e. media files, documents, backups, etc. So how do you decide which NAS to buy?

For everyone and anyone who asks me, I’ll always go with a dual-drive NAS. If you decide to go with a single drive NAS, you might as well go with USB disks like Seagate FreeAgents or WD Elements. So, basically you have to calculate how much storage you need. One area to start with is to see how much space you use in one year and how much that grows. My average storage needs (photos only) are about 600Gb/year. Chances are that won’t increase much unless I upgrade my cameras. I do budget a 10% increase. I do have other needs also so by the time I added everything in, it’s a large number.

Secondly, ask yourself f the NAS is your primary backup or not. If it is, it will need to be able to store all your backups. It’s good to take into account a 3-year plan so if you need 600Gb/year, then your NAS will be or must be able to grow to accomodate at least 2TB. This actually then dictates the size of your NAS. If it’s secondary storage (like in my case) where you have backups somewhere else (Hard drives, DVDs, BDs, etc) then the requirements are different. I wanted past 3-years of media (Photos & videos) on my NAS while my main backup stores everything. This required at least a capacity of 2.2TB at least which is why I went with a 4-drive unit. Most 2-drive NAS units max out at 2TB (2x2TB disks in mirrored/RAID1 config).

Finally, the next thing you need to consider is how fast you want to get the data off the NAS. I assume you’d be connecting at least via gigabit speeds. The specifications of the NAS play a part in the speed (excluding poor network speeds) aspect so normally I look at what CPU the NAS has along with the memory.

So what are my choices/recommendations?

Budget: DLink DNS-323
Cheaply priced (RM439/USD130), it’s the lowest cost 2-drive NAS I would buy myself.

I’ve only had experience with QNAP and Synology NAS units so that’s what I’ll stick with. You can go over to Smallnetbuilder and check their NAS reviews but not all are available locally in Malaysia. Here’s a handy performance chart for QNAP and Synology NASes.

Two-bay units:
Synology : DS210j or DS209
Qnap : TS-210 or TS-219

Two-bay units (higher performance):
Synology DS210+
Qnap TS-239 Pro II

Four-bay units:
Synology : DS410j
Qnap: TS-410 or TS-419P

Four-bay units (higher performance):
Synology : DS410
Qnap: TS-439 Pro II

note: this list above is from May 2010. If you need more space, you can consider the 5 and 6 bay models.

QNAP TS-439 Pro unboxing and mini-review

The big box

If you’ve been following this blog for a while, you’ll have noticed a few posts alluding to the search of some network storage to replace my 2-drive unit. I finally settled on the QNAP TS-439 Pro. Read the previous post about it or go to QNAP’s site to read more. Basically, I needed a compact, four-drive unit. Why four drives? It allows either two mirrored sets of disks (note: not necessarily RAID1) or RAID5 (with or without a spare). Going larger (5, 6 or 8 drive units) adds exponentially to the price but I wanted the use of the few 500Gb disks I have lying around. 500Gb is quite small but if I put them in a RAID5 set, I get 1TB (n-1). Later when I move some of my main storage disks to 1.5TB disks, I get another 500Gb to slot in as a spare drive (3x500Gb + 1 spare).

Other highlights for me were the hot-swap disk trays (lockable), multiple USB ports for printer sharing and dual-Gigabit LAN ports. The other stuff are frills. The dual gigabit Ethernet ports give you a fair bit of flexibility. You can configure two separate links for two separate networks, or some form of load-balancing, etc. Mine is configured for link aggregation group (LAG) mode. If you want to read more on that, which can get technical, Google for 802.3ad. In a nutshell, what LAG does is to create an aggregation group of network links that share the same speed and duplex settings. This requires a switch that supports LAG though and few consumer grade switches support it. The TS-439 Pro does have another option of using Adaptive load balancing. This bonds the network interfaces on the 439 and allows it to aggregate without any switch support. There’s a slight drop in performance but if you don’t have a switch that supports 802.3ad, it is the way to go. Did I mention two links means redundancy?

Pretty basic and unassuming, low power, low heat and quiet.

My primary use is to serve as my iTunes and media server (uPNP/TwonkyMedia), download stuff (BitTorrent), IP camera recorder, and a common file store to use between my PCs and notebooks in the house. My plan is to copy my photos there from camera, then once they’re sort of done (processing, etc), they can be moved to my File Server (which has 6x1Tb) in a RAID1+0 config. I’ve used jperf to do some testing to check the LAN bandwidth/switch speeds and for the TS-439, some regular file transfer timings.

First off, my gigabit LAN between Win Server 2003 R2 (dual-core Athlon, 6x1TB, 3Gb RAM, single link, the onboard NIC is died earlier this year so I’m running an Intel Gigabit CT off the PCIe x1 slot) and my Vista 64 SP2 client. I ran jperf over a few minutes with a five second interval. Min speed reported at 601,274Kbits/sec, max speed reported at 879,761Kbits/sec. Average the 30 readings and I get an average of 795,208Kbits/sec, or 776Mbits/sec or about 97Mbytes/sec. So let’s see how the 439 Pro transfers — remember, I have link aggregation on the TS-439.

1. Transfering 14,521Mbytes of photos. What I have is a mix of small and large files sizes. Large as in on average 26,912kb and small as in about 9kb (the XMP sidecar file). Transfer took about 320 seconds. 45.3MBytes/sec.

2. Transfering only the CR2 files took faster, clocking in about 261 seconds, or 55.5MBytes/sec.

3. Dual client access. Transfer a directory of photos and sidecar XMP files (12,672Mbytes and 11,760Mbytes). Start the transfer on client A then client B. Same target on NAS. Client A finished at 262 seconds. Client B finished at 302 seconds. Note that client B started transferring at roughly the 30 second mark of Client A. Average transfer speed is about 48.3Mbytes/sec for client A and 38.9Mbytes/sec for client B. Not too shabby considering both were hitting the NAS at the same time for about 87Mbytes/sec. Good enough for me.

Testing single disk setup

I’ve used it as a mapped drive for working on my photos and from Lightroom 3 beta 2 and Bridge CS4, the images feel very snappy. Not as quick of course compared to my local SATA drive but it’s not that obvious you’re working through a network. The lag on bridge in terms of refresh for example is noticeable only when you have three clients hitting the NAS but the fact is that its not terribly slow. My guess is that if Bridge refreshes my 800 photo directory on my local drive in 5 seconds, it takes about 8 or 9 on the NAS and perhaps 15+ seconds if you have multiple clients hitting F5 at the same time. Overall, I’m pretty satisfied. Maybe it’s time to look for dual-Gigabit port NICs for my client machines as well but I think the NAS will get faster when I up the RAM to 2Gb.

Fancy cover flow style admin interface

Overall, I’m pretty happy. It serves up my music to my iTunes, I can also listen to music/look at photos/watch movies on my Popcorn Hour C-200 via Twonkymedia server, record from all four of my IP cameras and work on a shared folder of photos. Not cheap but probably more cost effective to run than a standalone PC or server (if you factor in licensing, power, heat and noise). You can do other things with it as well though even thought I don’t such as running a Web or FTP server, etc.

If you want a more in-depth review, you can read it here.

Most administrative interfaces are web based now…

Network Attached Storage

From Wikipedia : A NAS unit is a computer connected to a network that only provides file-based data storage services to other devices on the network. Although it may technically be possible to run other software on a NAS unit, it is not designed to be a general purpose server.

NAS provides both storage and a file system. This is often contrasted with SAN (Storage Area Network), which provides only block-based storage and leaves file system concerns on the “client” side. SAN protocols are SCSI, Fibre Channel, iSCSI, ATA over Ethernet (AoE), or HyperSCSI. Despite their differences, SAN and NAS are not mutually exclusive, and may be combined as a SAN-NAS hybrid, offering both file-level protocols (NAS) and block-level protocols (SAN) from the same system. Considering I’m writing for home-users, a NAS makes more sense.

With the amount of data many photographers (and users) are generating, it’s become obvious that storage is a problem. For casual users, it probably may not be a problem in the beginning but it soon will be. I know of friends who after a few years, a kid or two and the amount of photos, videos, music, documents, scanned PDFs, etc start to add up to gigabytes. Burning to DVD (gosh, who burns CDs today?!) can alleviate some of the problem but with 4.5Gb (dual layer disks aren’t common as they’re not so cost effective), it’ll take a few DVDs for the average persons’ backup. Worse still, those DVDs may not be readable after a few years. A friend of mine burns two discs for each copy — and 3 years later found out that some are not readable. Good thing he had two copies as he’s managed to combine them to even out things so no loss occurred. So, he consolidated the storage. Where? Good old spinning platters. With the falling prices of hard drives, it’s a no brainer that disks are still the most reliable, cheap and effective storage for backup for most users today (most users here I mean home and small business perhaps). Reliable? Yes, if you have two disks and you replace them religiously every 36-months. That’s what I do. The benefit is that you’ll end up having larger disks too. My backup server has 1TB disks now. It started out with 160Gb and 250Gb disks (two pairs) for a capacity of 450Gb. My data very important to me so I change disks every two years. I then went to 320Gb and 500Gb (still two pairs) and now, I’ve got four 1Tb disks plus a pair 500Gb disks (these store my music, video and misc files). They’re going to 1.5TB disks soon (best price per Mb).

The problem is usually, you won’t want your backup server running non-stop. Mine’s on a UPS along with my network, and more but most casual users also don’t need access to their backups every single instant. They also normally don’t have another spare machine lying around. In many organizations today, they use the term near-line storage for things that can be retrieved faster that tape but slower than current online storage. Of course big organizations use fast disks arrays for online and slower and usually SATA disks for near-line storage. In my case, I’ll call my storage server near-line because it may not have been started up. Where’s my online storage? Well, it sits on a NAS, a QNAP TS-439 Pro. This is a bit too much for most home-users (they can go with a TS-210 or TS-219) instead. I’ve a RAID 5 set of 500Gb disks in there, giving me just under one Terabyte of available storage. It makes a good always on file-server, repository and immediate backup (Downloader Pro immediately makes a copy of my photos there). When time comes, it gets rysncd to my near-line storage server. The reason I got the 439 Pro was because it was on promotion. It’s been replaced by the Pro II (better CPU) and was the same price as the 419P. To me, the benefits were the faster (compared to 419P) CPU, and larger RAM (1Gb 439 Pro compared to 512Mb on the 419P) which translates to faster transfer speeds. The 439 Pro also has the memory on a SODIMM which means I can bump it up easily to 2Gb. QNAP’s disty over here still has a few units of 439 Pro if anyone is interested.

So what’s for the average home user? Well, if you have more than one computer in the house, would like to share some storage, do some backup, stream iTunes around the house, etc, then any one of these NAS units over here, here and here would serve you well. You’ll also notice that I’ve avoided any form of single drive device. That’s because most home users “think” that once it’s backed up, it’s going to be safe. Two drives are always better than one. If you’re on a tighter budget, get a pair of USB drives. Seagate or WD are good options. Just buy two and make sure your data is identical on each one. And, yes, please store them in separate places — at least a different room. My storage server and NAS are three walls and fifty-feet apart. Note: RAID does not prevent idiotic errors like deleting your only copy of the most important file or photo you ever have — the array isn’t going to care and will promptly erase all for you. In my case, well, I can still go back to either my storage server (100% read-only) or desktop.

My choice of 4-bay, well it’s more for RAID 5 as I’m using older disks for it (i.e. the ones retired from my storage server) so it’s good to have RAID5+1. RAID 5 capacity is (n-1) resulting in the available space of two disks, i.e. in a RAID 5 set of 3x500Gb, I get 2x500Gb usable. The +1? That’s the hot-spare in case something dies which is for the paranoid like myself. If you go with plain RAID5 on my setup, you’ll have 3×500 resulting in a usable 1.5TB.

I’ll post again why I chose the QNAP NAS plus a mini-review… I’ll stop here… more to come while I leave you with a pretty picture of my network appliances 🙂