The right raid array for NAS
 

I currently have two NAS servers which contain a single 3TB drive and I have run out of space so I am looking to replace them with something like this http://www.amazon.co.uk/gp/product/B...pf_rd_i=468294

My question is this:

I defo want to use raid 5 because I'll cry if a hdd fails and I lose everything but I would like to know if there is a way that I can still merge 3 drives together to create one volume like in raid 0 so I just see one big 12TB drive? I will be using the drive as a media server so I am assuming that the devices which view the media will just list the folders regardless of which drive they are on. From my perspective in terms of managing the data I don't want to have to worry about running out of space on a particular drive and then have to start putting the same type of content onto another drive. I would rather have one big 12TB volume and use as much space as I want to. As an example, say I have catergory a, b and c on there and had a drive for each because there are 3 categories, I might only have 500gb of category a but 6TB of category b and I don't want to have to have one drive full of category b and then have it spill onto another drive as well. If I had one big 12TB volume I could just have a folder for each and they would take up as much space as they needed to without me having to worry about how I organise the data.

Re: The right raid array for NAS
 

Mon General, you might care to await a contribution from Horseman who seems to know this stuff. I no longer recall my past on logical vs physical media.

Re: The right raid array for NAS
 

tYep - that's what RAID 5 looks like, RAID 0 except losing some capacity to the parity data. Both stripe data across disks so you see a single logical drive regardless of the number of physical drives.

You should be aware that you're going to lose 1/3rd of the entire space to parity data though, and that RAID 5 isn't exactly incredible as far as recovery of data goes. You may find that you'd rather simply back it all up for performance, or if you really want to be secure and don't mind losing the space use RAID 1+0.

Incidentally your storage requirements are insane. I can't even fill a single 3TB drive let alone 2 of them! Then again maybe your storage requirements are normal and I just don't have much content locally, I'm very 'cloudy'. :)

Re: The right raid array for NAS
 

that's good knews, I was under the impression that with raid 5 I would lose one of the 4tb drives to parity and the other 3 would remain seperate logical drives. If it stipes the data and it displays it as one logical drive like in raid 0 I'll be delighted because that is exactly what I wanted.

I know raid 1+0 is the ideal solution but I won't really gain capacity wise from that. As I mentioned above, I have already got 6TBs which are full and I wanted to double to 12TB. The only reason why I am going for a 16TB nas is because I thought I would lose 4tb to parity which still leaves me with the desired 12TB. If I did raid 1+0 I wouldn't really gain much because I would be back down to 8TB. I wanted to get the disk station and get rid of my two 3TB drives so it isn't as if it would be 8TB + 6TB (old drives) although I might consider keeping one of them.

Re: The right raid array for NAS
 

Synology products do allow you to expand volumes so multiple disks look like one drive. Not something I have done myself but I know it's possible.

Keep in mind that you won't be able to put your existing disks in to a Synology/Qnap/etc without the NAS wanting to wipe and prepare those disks for use in the array. Either putting in fresh disks and copying over or backing up somewhere else first would be an option in this type of scenario.

Finding my two bay 4GB NAS isn't enough so looking to upgrade too. The Synology DS 412+ is a better option than the 413J looking at the specs. 413J is a Marvel Kirkwood 1.6Ghz ARM based chip with 512MB memory and USB2 whereas the 412+ is an Intel Atom 2.13Ghz dual core with 1GB memory and USB 3. The speed difference in using it should be a lot better, worth spending that little extra imo.

The way I look at things is I don't need the extra speed raid gives and a lot of the stuff on my disks can be got again. So I have no raid and only backup/mirror a few crucial directories from one disk to another. If one disk goes down I still have another copy of my data. Gives me peace of mind as well as more space overall. I share certain folders on each disk which makes it more simple for me to index folders with XBMC and such like although I am at mercy of the problem you explained above in relation to some things taking more space.

All Synology products have the same DSM software, so looking at mine, I think it's Disk groups which is the part that lets you expand volumes

https://www.cableforum.co.uk/images/local/2014/05/5.png

Re: The right raid array for NAS
 

The 413 sounds good and I like the idea that you can create a group of disks. Formatting etc isn't an issue because I was going to buy a 16TB NAS so it would already be populated with new drives. The only niggle I have got with all of this is the capacity vs redundancy arguement. I have got 3.5TB of various hdds attached to my pc locally so when I first started out I was able to backup stuff. I have already got too much to be able to go that now and I defo can't afford to backup 12TBs of stuff. I know I can download all of it again but it would be the time it takes to do it. I could keep my current two NAS' for backup purposes but I was going to get the synology and sell my buffalo and seagate.

I really do like the look of the 413+, the only bummer is that it doesn't mention a print server as one of the features and the 412 and 414 do.

Re: The right raid array for NAS
 

With broadband getting faster and faster, as well as my sources being reliable and fast, it made the decision of not backing up the majority of my files using RAID an easy choice. It's not for everyone though :)

The Synology software (DSM) is pretty much identical between all of their products, so if one product has print server capabilities, the others will. Could be they just missed it out in the description you saw. DSM 5 was recently released which gave all the new features to all their products which could take the update. Some of their older products, say 4 years and older for example, would be stuck on 4.3 or something like that but even then, they should all have pretty much the same capabilities but different specs and speed.

Re: The right raid array for NAS
 

me too everything of import to me are encrypted on online in various places.Even bunged my mp3 collection on a site where before I would have not bothered and just got what I wanted again if I lost them.

Re: The right raid array for NAS
 

Something to consider is perhaps buying a Microserver. I have this rather cheeky number in my living room.

Re: The right raid array for NAS
 

I was eyeing up the N54L a few years ago for a NAS but decided for once I didn't want the hassle of building and configuring everything from scratch. It was a hard choice as you would get much better specs for your money with a microserver. The fact they tend to be noisy too was another factor. Wanted it in the front room connected to a switch near the tv so glad I went with the DS213J at the time It has a fan but it's so quiet I can't actually hear it even with the tv turned off :)

Might reconsider a microserver once the whole property is properly network wired so I can stick one in a utility room or another room.

Re: The right raid array for NAS
 

That's a good deal.

Long term (don't really have the money to do it at the moment), I've been looking at a large NAS. Actually primarily so I can ensure the family computers are backed up (even though it's on site, it's better than nothing) but I'd like to store some media, and stream it. Yes, I know that most NAS drives can do DNLA, but I have a variety of devices and I'd like a device with enough power to convert the media to whatever form is needed on the fly..

I use a package called Mezzmo to stream and convert the media. Be interesting to see if that microserver is up to the task of on the fly conversion.

Re: The right raid array for NAS
 

In the long term I would think transcoding of streaming media will be needed much less. Media players, tv's and even phones are already at a point where they can play pretty much every raw format. Even the TV in my bedroom has DTS support so I can stream the same mkv's as I use in the front room without any transcoding at all. Same with the mobile phone/tablet with the correct player although for mobile network speed a low powered NAS seems sufficient to transcode to that bitrate.

Serviio is similar to Mezzmo (used both in the past) and the Synology NAS have a Serviio package anyone can install, althoug hmileage will vary depending in the power of the particular model.

Re: The right raid array for NAS
 

HP keep doing cash back deals on their micro servers so keep your eyes peeled on HUKD

Re: The right raid array for NAS
 

The HP microservers are indeed an exceedingly good deal. If my array didn't require 36 drive bays, I would probably be using one as well.

It also gives you the advantages of flexibility, allowing you to use more advanced filesystems like ZFS or BTRFS or UnRAID.

Nonetheless I see the original question has already been answered...

---------- Post added at 00:16 ---------- Previous post was at 00:07 ----------

What he said. Also something that a lot of people overlook... RAID is not a substitute for a backup.

I cannot emphasize this enough.

Also I would suggest RAID 6 over RAID 1+0 if you wanted more security - RAID6 is guaranteed to survive any combination of any 2 drive failures, RAID1+0 will lose data in 33% of possible 2-drive failure combinations (and not to be confused with RAID 0+1 which will lose data in 66% of 2-drive failures).

If you call a 4-bay NAS filled with 4TB drives is insane, I'd love to know how you'd describe my NAS setup in my utility room :p:

https://www.cableforum.co.uk/images/local/2014/05/6.jpg

---------- Post added at 00:19 ---------- Previous post was at 00:16 ----------

The HP is notoriously quiet thanks to its large diameter fans and passively cooled mainboard.

As far as the hassle of building and configuring - there's quite a few NAS-dedicated *nix distributions out there that install as an appliance and present the same sort of administrative web interface as the Synology NAS units.

---------- Post added at 00:28 ---------- Previous post was at 00:19 ----------

It depends more on the source content to be honest. Streaming encoders are really fast these days and use far less resources than archival encoders. I have a 2Ghz dual-core AMD Athlon64 system which is actually perfectly sufficient for encoding 1080p streaming content to various devices, as long as the source bitrate doesn't exceed ~20Mbps or so. Above that bitrate, it has too little CPU power to decode the source content quickly enough!

The N54L is a much newer architecture and faster so should have no problems.

Re: The right raid array for NAS
 

Read a number of reviews on the N54L that said it was too noisy to sit in a front room. So might be quieter than comparable size units but sounded noisy enough to annoy.

FreeNAS seems to be pretty popular as an alternative software and there is even a modified version of the synology DSM software called XPEnology that works in a virtual machine, although not made by them. Still a bit more configuring and mucking about than I wanted to do at the moment in time I brought mine :)

Re: The right raid array for NAS
 

Hmm, maybe I just have really poor standards for "quiet". All my machines use at least 150w while idle so anything with less than six fans or 100w power consumption under load is automatically "quiet" in comparison to what I have :P

Re: The right raid array for NAS
 

Some are more sensitive than sound than others but looking at your setup, you are accustomed to much more sound anyway :D

It's funny how an office can sound pretty quiet until there is a power cut and then you realise how much noise the computer fans and air conditioning make all day every day!

Re: The right raid array for NAS
 

Heh. While rack servers do tend to be pretty noisy out of the box in that particular one I've built some custom fan control relays to keep the noise down, it's a lot quieter than you'd expect. Nothing like the server rooms they are normally used in, where providing hearing protection for employees is a mandatory health and safety requirement...

That said my desktop has one of the noisiest graphics cards on the market today and boy does that thing make a racket... I'm sure my portable vacuum is quieter (and probably has less airflow too!)

Re: The right raid array for NAS
 

what do you use your array for and what is the cumulative capacity. I am genuinely curious because when I get my new NAS I'll have about 31TB of storage altogether which I thought was a bit OTT.

Re: The right raid array for NAS
 

My N54 is very quiet. It is no louder than a PVR, no-one notices it. I don't work in a noisy environment so would notice a loud bit of kit and do when I fire Big Daddy Dell up.

No idea what would require that amount of storage. I use less than 3TB across all devices including 1TB devoted to lab/VMs. I guess video content, that's the usual suspect. Odd as it may sound given it is me nearly all of my video content is on its original Blu Rays or is streamed. I am not a big TV watcher.

Re: The right raid array for NAS
 

Interesting to hear different opinions on the fan noise of the N54. Need to listen to one myself maybe.

Some people rip their blu-rays to a NAS so they can do away with using the disks and easily browse their media from any location on their network, or even when out and about on mobile devices. Others download similar material but the premise is the same, a central media library. If you do a full bluray you are looking around 56GB per film although you can remux quality down slightly and keep only DTS-MA 5.1 for around 25GB per film. If you look at downloads they are around 7GB per film for a 720 with DTS sound at 1.5Kbps or around 11Gb for it at 1080. So times that by x amount of movies in your library.

Streaming movies from a service is good enough quality for most people and would save the need for the storage but some prefer a higher bitrate for the video on their large tv and better sound quality for their surround sound setup.

I tend to download TV shows even though I can watch them live or through a catch up service, simply because I can automate it completely with the NAS and use the same easy to use interface (xbmc) for watching everything, rather than flicking between inputs to different devices for different things and multiple inferior front ends. They get deleted after being watched but sometimes it takes a while to catch up on them, so the GB of them do stack up, especially with some of them being 1080p.

Add on top music, then all the windows and linux iso's, VM backups, home video backups, lossless music samples for creating music etc and space can easily get taken.

Re: The right raid array for NAS
 

I use it for... well... Storage. The main array is a 76TB array in triple-parity mode giving 64TB usable. Backup storage is a 25TB array.

Aside from the usual suspects (movies, porn, other downloaded warez) it also stores backups of most of my machines, and my own photo/video collection. And several dozen virtual machines I can't be bothered going through before deleting.

I also used to do a lot of freelance data recovery work and imaging four or five 500GB-1TB drives at a time, plus extra space to store the data recovered off them...

---------- Post added at 12:14 ---------- Previous post was at 12:09 ----------

The storage I "need" these days is probably closer to about 10TB. 2-3TBs are my own photo/video collection, as a photographer I'm pretty lazy and shoot everything in maximum quality RAW+JPEG so a single image (which my camera takes 5 per second of) is 30MB. I sometimes shoot as many as 2000 a day and over a decade it adds up...

Also my camera's hacked to record HD video at 200Mbps which probably doesn't help.

Do I "require" any of it? Probably not, given the number of times I've had a drive/memory card fail and lose hundreds of gigabtyes of hugely important data, yet I'm still alive...

---------- Post added at 12:18 ---------- Previous post was at 12:14 ----------

Music is probably the one thing that really needs to be on storage, since I play my whole music collection on shuffle all day every day. Changing CDs every 3 minutes would be a PITA.

Movies/Blu-Rays etc. I tend to find I only ever watch once, if I ever watch it again it's several years later, it could probably be better off/cheaper in a WORM tape archive. Or just on disk, in which case I'd have to to stop being lazy and actually insert a disk once every few weeks...

Re: The right raid array for NAS
 

This is a great example of how Technology has advanced in quality and price in the last ten or so years.

In 2001, I undertook a trip to the USA (on behalf of BT Cellnet, when I was the IT Programme Manager on the Data Warehousing programme) - we visited a number of sites (Pittsburg, Little Rock, St Louis, and Montreal) to look at what was (at the time) leading edge in DW, focusing on Telecoms and CRM companies. The site in Little Rock had one of the biggest (not including NSA) Data Warehouses for CRM, and it was 25TB useable space (they used RAID1 at the time).

How things have changed......:D

Re: The right raid array for NAS
 

Well it sure has advanced in capability though I'm not so sure about price, I did spend a whole 2-3 months' salary on it :P

Miniaturization has been incredible though. An 80GB MP3 player from 10 years ago:
http://img52.imageshack.us/img52/50/p1010855w.jpg
And a 128GB one today:
http://2.imimg.com/data2/KC/SM/MY-25...le-250x250.jpg

I think the 2000's were probably the heyday of hard drive technology though, since about 2010 or so we've seen far less progress :(

Re: The right raid array for NAS
 

Maxing out on bit density per platter. SSDs are where it's at now.

Re: The right raid array for NAS
 

Everything we have now is better quality. Cameras and video cameras (including mobile phones) have more megapixels which = more space and we love to have the best possible quality if we can. Movies are better quality after going from DVD to bluray. People want to store lossless music such as FLAC instead of the lower quality MP3. People are also becoming more aware of backups and raid.

Luckily hard drives have got bigger and in general cost less per GB as time goes by :)

I'm also guilty of not cleaning up old computers or backups, so have a number of messy home directories backup up from as long as 15 years ago, as well as some very old virtual machines I should actually delete. There may be a time I can't find something and want to fire them up to see if it's on them though :p

Re: The right raid array for NAS
 

Well there's still HAMR and shingled recording to come, the latter being a pretty desperate and backwards move IMO.

SSDs on the other hand, I've had too many fail disastrously to put any trust in them anymore, it seems they're yet to figure out how to design them with any sort of sensible failure mode.

Plus, aren't we already nearing the limits of process shrinking and write endurance on stupidly tiny 12nm or so NANDs as well?

Re: The right raid array for NAS
 

3D NAND is your friend.

Prices on SSDs have dropped a ton. I purchased a 240GB SSD a couple of years back at 2 quid per GB, got a 240GB a month ago with better read and write performance for 33p per GB.

I always install monitoring on the SSD to keep an eye on the individual segments as they fail.

Re: The right raid array for NAS
 

Yeah prices have dropped like mad, though again the rate of decrease seems to have slowed. My 256GB SSD (mid-range, so not the cheapest) bought in late 2012 was £120, or 47p per gigabyte.

Monitoring is all good and all, if wear is the actual problem. Unfortunately often they show no signs of wear before one day the controller just catastrophically fails. Not only catastrophically failing itself, but then going on to explicitly overwrite known-good data while the device is inaccessible! Go figure.

Plus you can't always monitor SD cards properly, especially when used in phones or cameras.