[crussader]

I know people are going to call me crazy, but I don't see the rationale for spending the extra money to implement RAID on a NAS that is used simply for content streaming. Even with RAID, you still need a backup of the files anyway. If once every two years or so you lose a drive, just reload it from the backup. Huge cost savings. That means more money for more storage. Spend the money on storage space, not on redundancy.

Can someone explain the benefit?

 

[John Sully]

If you want availability, RAID 1 is the solution -- even if you lose a drive content is still available. If you need an extremely large amount of storage, RAID 5 or even better RAID 6 is about the only way to get a unified filesystem with more than about 8Tb of storage. The problem with large arrays is, as always, backup, and this is even true if you are only using 8Tb drives in a RAID 0 configuration. You can also use one of the hybrid RAID solutions which combine mirroring with RAID 5 or 6.

 

[crussader]

I understand about availability, but look at how much you are spending for that availability, and just how critical is it?

In my case, I have a pair of NAS units. Each is a two bay unit. The four bays are loaded with 4tb drives. The drives are not pooled. Each drive is an independent volume. NAS 1 contains my dvd collection (about 6.5tb). NAS 2 contains my blu rays (currently 5tb and growing).

If I lose a drive, I will not have access to a portion of my media, but I will still have plenty to watch. I certainly won't be starved for entertainment. I can't see it being so critical that I see a particular movie that I would want to spend hundreds or thousands of extra dollars to do a combined mirroring RAID set up.

If I felt it was critical, I would keep a spare drive on hand. In the event of a failure I could swap the drive, reload the movie file I just had to see, and be up and running in 30 minutes.

 

[crussader]

...about the only way to get a unified filesystem with more than about 8Tb of storage...

Is there a particular reason the filesystem needs to be unified?

 

[robnix]

It's very simple. My time is more valuable to me than the couple of hundred dollars that it costs to go RAID6 vs no RAID at all. I'd rather be doing something else besides re-ripping blurays because of a drive failure.

 

[crussader]

...My time is more valuable to me than the couple of hundred dollars that it costs to go RAID6 vs no RAID at all.

We are talking about way more than a couple hundred dollars. I have 16tb of NAS storage that I put together for right at $1000. And, I didn't go for the cheap route. My drives are WD Reds and one NAS is a QNAP and the other is the latest WD box. Tell me how I get 16tb of storage protected by RAID 6 for $1200.

I'd rather be doing something else besides re-ripping blurays because of a drive failure.

RAID is not a protection against having to re-rip. RAID is no substitution for a back-up. What if the NAS box itself fails. I don't have RAID but I won't have to re-rip. If a drive fails, I replace it and copy the files from my back up. I start the copy before I go to bed, and by the time I get home from work the next day, the files are restored. Doesn't cost me any time at all.

 

[tdallen]

Just curious, what is your backup solution? For a lot of people backup of their media collection is the original Blu-Ray/DVD disks and re-ripping is a tedious restoration method.

 

[John Sully]

Is there a particular reason the filesystem needs to be unified?

Mostly for convenience and ease of use.

 

[ajkrishock]

I understand about availability, but look at how much you are spending for that availability, and just how critical is it?

In my case, I have a pair of NAS units. Each is a two bay unit. The four bays are loaded with 4tb drives. The drives are not pooled. Each drive is an independent volume. NAS 1 contains my dvd collection (about 6.5tb). NAS 2 contains my blu rays (currently 5tb and growing).

If I lose a drive, I will not have access to a portion of my media, but I will still have plenty to watch. I certainly won't be starved for entertainment. I can't see it being so critical that I see a particular movie that I would want to spend hundreds or thousands of extra dollars to do a combined mirroring RAID set up.

If I felt it was critical, I would keep a spare drive on hand. In the event of a failure I could swap the drive, reload the movie file I just had to see, and be up and running in 30 minutes.

I just bought four 2 Tb Western Digital drives for my RAID 5 array. I spent ~$250 total. Hard drive space is cheap. Ultimately, What kind of solution you decide on depends on how much you're willing to spend, what your content is worth to you and your family, and how much pain you're willing to bear in terms of possibly losing content, downtime, and the amount of time you are personally willing to spend backing up/restoring content.

For me, my movie collection contains a lot of older, hard to find movies that I keep for nostalgia. I've been doing a lot of that since my father passed away. I also have a lot of the sci-fi movies that I grew up with as a kid so my son can watch them (and maybe understand my jokes a little better). The amount of pain I'd have to bear to restore all that content far exceeds the money & time I spend to protect against loss.

I just had a 1 Tb drive drop out of my RAID 5 array (prior to the rebuild using the 2 TB drives). I ran degraded for a week while I waited for the 2Tb drives to arrive. After that, it took maybe a couple of days to rebuild the array and restore my content. I lost nothing.

 

[robnix]

We are talking about way more than a couple hundred dollars. I have 16tb of NAS storage that I put together for right at $1000. And, I didn't go for the cheap route. My drives are WD Reds and one NAS is a QNAP and the other is the latest WD box. Tell me how I get 16tb of storage protected by RAID 6 for $1200.

1 Unraid License = $70.00 (sure, not officially RAID 6 but you can setup 2 parity disks and 4 Data disks)
6x4TB WD Green Drives = $798.000 (no need for Reds, unraid works fine with Green drives)
1 NXZT Source 220 = $63.00
1 Asus H871-Plus/Intel G3220/Crucial Ballistix RAM= $210.00
EVGA 500w PS. = $40.00

$1250 for 16TB with 2 parity drives. Wait...$1260, you'll need a USB stick for UNRaid. These are all current prices at Amazon. Sorry I didn't hit $1200, but I splurged on a few items.

RAID is not a protection against having to re-rip. RAID is no substitution for a back-up. What if the NAS box itself fails. I don't have RAID but I won't have to re-rip. If a drive fails, I replace it and copy the files from my back up. I start the copy before I go to bed, and by the time I get home from work the next day, the files are restored. Doesn't cost me any time at all.

Of course it's protection against having to rerip. It's certainly not perfect but it provides protection against downtime which is what RAID is intended for. I'm willing to take the chance that I can recover a failed drive before I have three failures. Regardless, I thought you said earlier that you would just rerip the disks instead of restoring, but now you're saying you restore from backup. So you're backing up your NAS to another NAS with the same amount of storage? If so then that's certainly some interesting logic. Instead of paying for disk redundancy you'd rather put the same money into enough to disk to backup one NAS to another.

Just curious, what is your backup solution? For a lot of people backup of their media collection is the original Blu-Ray/DVD disks and re-ripping is a tedious restoration method.

For my blurays that's certainly my backup solution. My personal data gets backed up to an online service, but all my media gets ripped and stored in a box under the stairs.

 

[Kelson]

I know people are going to call me crazy, but I don't see the rationale for spending the extra money to implement RAID on a NAS that is used simply for content streaming.

I won't call you crazy -- I agree to an extent.
IMHO a hardware RAID solution is overkill and restrictive for a media server application. Hardware RAID is most effective for live data streams that are frequently read and written like in a business environment. I find no need for that type of protection or that kind of hardware in a media server that Writes content to the array very infrequently and spends >95% of its time in Read operations, serving the files on its disks. I prefer a small PC with USB-3 ports and PCIe slots for eSATA port multiplier cards to run a soft-RAID disk farm.

As a single example: A small PC running Win-7 and FlexRaid with a Mediasonic 8-drive eSATA card and a Mediasonic Probox 8-bay drive expansion tower. Start with 2x4TB drives, assign one as parity and fill the first drive with content. I fill my drives completely leaving only 8-10GB of free space -- afterwards that drive is only read from. The soft RAID will update the parity disk at night (or on demand) and not interfere with system performance during active use. Add 4TB drives as needed, one by one, to the array until the tower is full to give you 28TB of storage protected against single disk failure. Each disk is independent with the content you put on it and readable by any PC should you decide to remove it from the array. Need more storage? Add a second eSATA card and 8-bay tower and start a new 8-drive array for an additional 28TB of storage.

There are many permutations on this including UnRaid but they all share the same theme -- you don't need the real-time performance or higher cost of a hardware RAID system for a media server.

The cost of a single 4TB drive is all it takes to provide some protection so that you don't have to re-rip a bunch of disks should a drive fail. That is a convenience cost since all the drives are independent so a failed drive would lose only what is on the drive and not the whole array. If you don't mind re-ripping the content of a 4TB drive then forget the soft RAID and keep all 32TB for content storage.

 

[Haywood Jablomi]

Backups become impractical when your storage exceeds a certain size.

 

[crussader]

1 Unraid License = $70.00 (sure, not officially RAID 6 but you can setup 2 parity disks and 4 Data disks)
6x4TB WD Green Drives = $798.000 (no need for Reds, unraid works fine with Green drives)
1 NXZT Source 220 = $63.00
1 Asus H871-Plus/Intel G3220/Crucial Ballistix RAM= $210.00
EVGA 500w PS. = $40.00

So I could do it if I went with cheaper drives and added a half built computer to the mix of things that have to be kept running and maintained.

I'm willing to take the chance that I can recover a failed drive before I have three failures.

What happens when the raid box itself fails?

Regardless, I thought you said earlier that you would just rerip the disks instead of restoring

I never said that.

So you're backing up your NAS to another NAS with the same amount of storage?

I never said that either. I have some 2tb and 3tb usb green drives with the data mirrored that are sitting in a drawer in case they are ever needed.

Instead of paying for disk redundancy you'd rather put the same money into enough to disk to backup one NAS to another.

A backup is needed. I would hate to rely on re-ripping as my backup.

 

[crussader]

IMHO a hardware RAID solution is overkill and restrictive for a media server application. Hardware RAID is most effective for live data streams that are frequently read and written like in a business environment. I find no need for that type of protection or that kind of hardware in a media server that Writes content to the array very infrequently and spends >95% of its time in Read operations, serving the files on its disks.

This was the main point I was trying to make by starting this thread. Thanks for the eloquent and concise summary.

When I started to consider storage solutions, as a newbie I was a bit discouraged by the seemingly universal insistence that a full blown RAID setup was a necessity. It turned me off of the NAS concept for a long time. I'm glad I discovered there are alternatives.

 

[Kelson]

A commercial RAID 5 NAS has the strong appeal of being an easy to set-up network appliance. Many people are willing to pay for that convenience, etc. and I fully support their decision if it is the right thing for them. For me, a RAID 5 NAS didn't fit with the storage direction I wanted to go in and my usage as a media server did not require the real-time data protection they provide. That freed me to pursue alternatives that fit with my goals.

 

[robnix]

So I could do it if I went with cheaper drives and added a half built computer to the mix of things that have to be kept running and maintained.


What happens when the raid box itself fails?

The features that you get in the RED/NAS drives that differentiate them from the Green/Desktop drives simply aren't needed unless you're running hardware RAID. Software RAID solutions like Synology/Qnap and drive pooling solutions like Unraid and Flexraid don't use these features. All the consumer gets by paying extra for RED drives is a longer warranty.

If the RAID box fails, you're fine. Unraid isn't RAID, v5 uses ext3,v6 uses xfs. The drives can be read individually on any system that can boot Linux. Flexraid uses NTFS, the drives can be read individually by any system that can boot Windows. Synology and QNAP both use ext4 and Linux software raid, so as long as the drives are OK you can mount them with any Linux system as a group and read the data.

Even with a true hardware raid solution the drives can always be attached to a same brand controller and remounted.

I never said that.

Post #3 - maybe I misunderstood.

If I felt it was critical, I would keep a spare drive on hand. In the event of a failure I could swap the drive, reload the movie file I just had to see, and be up and running in 30 minutes.

I never said that either. I have some 2tb and 3tb usb green drives with the data mirrored that are sitting in a drawer in case they are ever needed.

So you're still paying to have idle drives laying around instead of using any sort of redundancy.

A backup is needed. I would hate to rely on re-ripping as my backup.

I agree, that's why my truly important data goes offsite, photos, documents, household inventory etc... USB drives in a drawer are lost backups just waiting to happen. For my BR's..as @Haywood Jablomi stated earlier, "at a certain point backups become impractical". I have 29TB of movies, it's simply not practical nor is it cost efficient to back it up, 2 parity disks give me enough peace of mind to live with the risk.

 

[smitbret]

We are talking about way more than a couple hundred dollars. I have 16tb of NAS storage that I put together for right at $1000. And, I didn't go for the cheap route. My drives are WD Reds and one NAS is a QNAP and the other is the latest WD box. Tell me how I get 16tb of storage protected by RAID 6 for $1200.

Build a cheap Linux box running SnapRAID and fill it with 7 x 3TB Toshiba consumer HDDs @ $90/per. If you have an old PC lying around then all you need is the HDDs and an SATA adapter card for $20.

But I agree, how to protect the data is a huge factor to consider when building a server or NAS.

Quite frankly, RAID in any fashion is probably overkill for home use. Most people would be served just as well by just pooling drives JBOD style. But they still need backup in some fashion. A 2nd NAS, of the same size, on the other end of the house or in the garage would be ideal, but hardly practical for most people. Certainly it wouldn't be the most cost effective solution for all but a tiny handful.

That's why I went FlexRAID and their version of RAID 6 (unRAID and SnapRAID would be just as effective); One server that can handle 2 simultaneous HDD failures. I went this route over a hardware raid or ZFS solution with this in mind:

#1 - I know that I have had only 1 HDD failure in the last 12 years that wasn't due to being dropped. So my odds of having an unrecoverable crash is small enough with RAID 5, let alone RAID 6.

#2 - I can expand the array by simply adding more drives. No need to break up the array or worry about pooling multiple arrays.

#3 - If, somehow, I get 3 simultaneous drive failures I only lose the data on the drives that actually failed. With FlexRAID, unRAID and SnapRAID, I can simply break up the array and import the drives into window and use the drive as a standalone. For this reason I don't swap smaller drives up to bigger HDDs, I just add more and spread the data out across more drives. If I end up re-ripping I don't have to re-rip everything.

#4 - My backup is a 2TB external HDD. I can fit all of my photos, Home Videos, Documents and Music on it. Movies can be re ripped but knowing about factor #3 this isn't as big a task as it would seem.

robnix nailed it on the head. At some point a full backup just becomes impractical, especially for something that would not alterably change my life if I lost it permanently.

 

[tdallen]

I never said that either. I have some 2tb and 3tb usb green drives with the data mirrored that are sitting in a drawer in case they are ever needed.

A backup is needed. I would hate to rely on re-ripping as my backup.

With all due respect, if you've mirrored all your disks you basically have implemented a form of RAID. You have an offline/near-line RAID 1 setup - disk mirroring using disks which are offline but can be quickly migrated to online. RAID 1 is one of the most conservative forms of RAID in that it duplicates storage. Compared to other forms of RAID there are advantages to your strategy (essentially two backups - disk and original optical) and disadvantages (more costly due to increased storage needs, real time redundancy and recovery).

Re-ripping is a perfectly viable backup strategy, if you are willing to tolerate the slow recovery time of offline backups. Since you have implemented both near-line and offline backups you've got some additional recovery options, at the expense of duplicate magnetic storage. If I were you, I'd move one of my backups offsite - then you really have robust recovery options. That's a piece I don't have with my software RAID-5/re-rip strategy.