Computer Audiophile Pocket Server C.A.P.S. v4 Cortes

If one drive goes down, you may lose data on both drives because the mirrored pair automatically changes data on both drives.

Drive failure in the modern RAID context is a number of media I/O errors exceeding firmware retry limit. Those errors are per disk sector or block of allocation. I/O errors are caught by the RAID manager and used as a criteria to take the failed disk offline.

RAID1 does not mirror data from one disk to another. Here is how it works (simplified):

1. When a write request is received from a process an attempt is made to write the data from buffer to both disks, in most cases simultaneously. If the data in the write request is garbage, then that garbage will be written to both disks. Not a fault of RAID1.

1.a. if one write fails, then that disk is taken offline and the RAID pair declared as degraded, with whatever notification follow-up happening. It is up to the user to replace the failed drive. The still good drive continues to operate and is not aware of the other drive's failure. No bad data is written on a functional drive because of another drive's failure.

1.b. If both writes fail, then the whole RAID is announced as failed and taken offline. No further IO is allowed to either of the disks without user's intervention.

2. When a read request is received from a process, an attempt is made to read data from one or both disks. Read policy is determined by the RAID programmer, and certainly depends on the current failure state of disks, striping configuration, etc. Again, there are no drive writes happening at this point.

2.ab. Read failures handling is close enough to write failures handling, so see the 1.a and 1.b items.

3. After user believes they got a good drive installed instead of the failed one, then they can issue a command to the RAID manager to restore the data from the old functional drive to the newly-installed drive. It is the user's responsibility to enter the command correctly and the new disk will receive exactly the data contained on the old functional disk. It is a bit more complicated, as simultaneously the whole RAID will accommodate read/write requests from the system.

If operated properly, RAID1 will protect from a single drive failure. A double drive failure, which is when the second drive fails before the first failed one replaced and restored, is not protected against - exactly because the last copy available to RAID manager gets corrupted and the RAID manager has no source for data restore. This is where the backup comes handy.

If it is the controller that is fubared then you may really be up the creek.

If it is the controller firmware which is buggy, then yes, the RAID1 may be doomed. However, those firmware issues are rarely last for long - and no vendor reputation is a replacement for reading early adopters' reviews. You are also likely to discover this early in the RAID lifecycle. Similarly, firmware may be (and often is) buggy on SATA controllers or MB chipsets so there is no added risk - but rather a replaced risk. If one uses a software RAID manager it is the same thing - those are well tested because of a very large user base. And one still should be wary of new software releases.

Again, at the end of the day RAID is not a backup and will not save from every imaginable failure. But it will speed up recovery from some of reasonably frequent failures.

I said "may" result in data lass - never said "will". There are still scenarios where this "may" happen. It still remains that if you delete or a virus or malware writes to the disk this gets propagated across both drives.

If you are raiding music files for a home server, there are easier and for most of us better ways of mirroring data across two discs.

I encourage the readers to google raid1 and decide for themselves if this is worth it.

But it will speed up recovery from some of reasonably frequent failures.

I'm not disputing this. I'm saying raid1 is a poor choice for most people for a home music server, why open yourself to additional points of failure when there are other ways to achieve data duplication when the benefits are for those really in the corporate realm where uptime is important?

I could not see how RAID would be good for any audio server. More things constantly running in the background.

Wow Chris, You really let the dogs out with this one. I am amazed at the controversy over a highly capable server build. I guess it just shows how fractured and diverse the hobby is becoming. Granted, it is massive overkill for most and probably way beyond the build and operate capabilities of most, your article showed what is possible for those who wish to put forth the effort and money. And, by the money, I mean the amount of music software one would need to own to justify a server like this. If some has $40,000 or more tied up in software and could really use this kind of horsepower, the $2,000 build cost is trivial. I suspect that going forward more and more of us are going to leave the server end of things to Edgecast or Amazon or Google and let Tidal, Qobuz and the future streaming services lease that stuff from them and send us the music over a longer wire that unfortunately won't be an AQ product. We will use a dedicated music client (like the Aries) controlled by a multi-purpose device (like the iPad) to send music to our systems. We may keep a limited amount of music local but it would not require this kind of capability. This one will sizzle for quite a while.

Bob

Unless you need massive amounts of storage, your best bang for the buck these days is a ThinkServer TS140. Amazon and Newegg have been running regular sales for various configurations, and I recently purchased an E3-1225v3 based model, 4G ECC RAM, no HDD and no OS for ~350. No hotswap bays, but 4 internal bays with a 4x4TB RAID10 configuration is plenty of storage for my needs. Mobo is based on the Intel C226 chipset (Haswell) and has IPMI as well as RSTe -- I'm running Windows 2012 R2 Storage Spaces and software RAID. Best part is that the thing is absolutely dead silent (no fan noise) and comes with 1 year of support.

 

For those who need more storage, the larger TS440 includes 8 hotswap SATA/SAS bays matched to an LSI RAID controller. This is also on sale w/ E3-1225v3 for around 400 bucks. This machine is larger and heavier, and is definitely not silent as it includes a redundant capable PSU with high RPM fan, but is quieter than most front office servers. Plan on spending around 17 bucks each for HDD trays which aren't include, but I still consider this to be a bargain since the LSI RAID card itself retails for around 200 bucks and you get 1 year of Lenovo support as well.

The TS140 servers are fantastic value. I have just bought a couple for use as a media server, 4gb RAM, 2x500GB enterprise disks, Windows Server 2012 r2 Essentials, 3 year on-site (four hour response) warranty for under £500 ($800), inlcuding VAT (UK sales tax) @ 20%. I intend to put a couple of 6tb drives inside and use as a server for movies and music and use the second server as a full backup.

Just checked in and wow it didn't take long for someone to bash Chris's idea's.

Well maybe the bashers just need to put together their own device, post their ideas on the forum and let the folks have at it.

Quite frankly I am missing your point about why RAID1 is a bad idea. The issues you bring up are not the ones RAID1 addresses by design, so they are not applicable. The issues you mention normally addressed by backup arrangements, and RAID is not backup. More so, Chris writes about backup separately and how it may interact administratively with RAID1, but nowhere I see he conflates the two. Hyping "potential for disaster with RAID1" is akin saying that if RAID1 can be used poorly (i.e. it is not fool-proof), then it should not be used at all.

 

In this case, I think that the use of RAID1 is quite appropriate for the stated purpose of simpler recovery from a single disk failure.

Well, RAID1 is looked at as backup by many folks. It isn't but it is looked at that way.

RAID5 or RAID10 are my preferences, as you get more performance boost from them. But they reauire more drives of course.

Chris did mention there was plenty of room in the case to install drives for backup and that the RAID1 configuration was for high availability - not backup.

Backup is, if anything, even more important on a server than on a standalone device, woukd you not agree?

Backups are copies of your important data/music that you keep offsite or in a fireproof container. In a volatile (i.e lots of new data added/changed regularly) environment they should be copied to regularly. Backups have absolutely NOTHING to do with RAID discussions, which are simply about failsafe disc usage. I find it bizarre that they are discussed together and confused. If your house burns down or all your electronics are stolen your RAID choices are completely irrelevant.

Backup is, if anything, even more important on a server than on a standalone device, would you not agree?

A decision on a best fit storage solution is so much context dependent that I do not see a utility to generally discuss it. It may make sense to mention what may be considered when designing it. For me personally backup goes first before any other concerns. I usually have at least two backup mechanisms in place, both out of the system, one of them off-site, resource permitting.

For both backup and availability solutions one should consider use cases, available expertise, available time to create and manage the solution, costs, existing infrastructure. I personally run on a combination of 2x2TB RAID1 and 5x3TB RAID6, which as of yesterday moved from Synology to a Xubuntu system (with a failed HDD fun in the process). That RAID6 hosts backups for everything as far as media goes - about 15GB FLACs, 30k+ raw photos and negligible number of home videos. I have not had a problem of co-hosting many things on the same file server - may be because my Media Center is set to play files from memory instead of disk and I only listen via the DAC/headphones. I also seem not to be a music quality gourmet in the scope of this forum, meaning that I am OK to expect a music interrupt when spinning up 10-15 Vagrant VMs on the laptop.

So when talking about storage, backup is not an interesting point for me personally but rather an obvious prerequisite. I assumed that Chis treated it similarly - focusing on how the storage can be improved beyond a backup strategy, which is too context-dependant to discuss in that article.

The TS140 servers are fantastic value. I have just bought a couple for use as a media server, 4gb RAM, 2x500GB enterprise disks, Windows Server 2012 r2 Essentials, 3 year on-site (four hour response) warranty for under £500 ($800), inlcuding VAT (UK sales tax) @ 20%. I intend to put a couple of 6tb drives inside and use as a server for movies and music and use the second server as a full backup.

Is the Win Server 2012 r2 license limited to "per machine" as usual, meaning if the particular TS140 breaks, the Win Server cannot be resintalled on another machine?

Well, RAID1 is looked at as backup by many folks. It isn't but it is looked at that way.

 

RAID5 or RAID10 are my preferences, as you get more performance boost from them. But they reauire more drives of course.

 

Chris did mention there was plenty of room in the case to install drives for backup and that the RAID1 configuration was for high availability - not backup.

 

Backup is, if anything, even more important on a server than on a standalone device, woukd you not agree?

Straight from Adaptec's site:

Adaptec - Which RAID Level is Right for Me?

You do not get more performance boost from RAID 5 (RAID 10 perhaps) compared to RAID 0 or RAID 1. There is more computing overhead to stripe data across drives in a 3+ drive RAID array. You take a hit on writing data.

And as Ted B mentions, RAID should never be considered a method of backup.

In case anyone is interested in TS140. Newegg is selling the Xeon version for 320 + tax (if applicable) via eBay

Mods if the message is not appropriate for the discussion please delete.

Is the Win Server 2012 r2 license limited to "per machine" as usual, meaning if the particular TS140 breaks, the Win Server cannot be resintalled on another machine?

The license can be moved to another machine simply by calling MS support. If you have access to an MSDN subscription (check your company or school if they get a discount) the 2012 R2 option is pretty cost effective. You get up to 5 R2 Standard license keys per subscription, and 5 more for R2 Essentials as well as all the other OS licenses. Otherwise, the OEM pricing for R2 Essentials is about $360, which is about 1/2 the price of R2 Standard.

Backups are copies of your important data/music that you keep offsite or in a fireproof container. In a volatile (i.e lots of new data added/changed regularly) environment they should be copied to regularly. Backups have absolutely NOTHING to do with RAID discussions, which are simply about failsafe disc usage. I find it bizarre that they are discussed together and confused. If your house burns down or all your electronics are stolen your RAID choices are completely irrelevant.

Dropbox Pro is a nice offsite backup option if your data is not too large. It's less than $100 a year for 1TB, and lan sync is nice for maintaining copies on multiple local machines.

Chris,

Thank you for putting this all together and pointing out limitations of traditional NAS drives.

I believe the disappointment expressed by some members is mostly due to the unfortunate timing - everyone was eagier to read about the CAPS V3 replacement, not the NAS replacement. If the NAS replacement article appeared last, instead of first, people would probably be quite enthusiastic about it.

As is, everyine has to wait a couple of more days

Straight from Adaptec's site:

 

Adaptec - Which RAID Level is Right for Me?

 

You do not get more performance boost from RAID 5 (RAID 10 perhaps) compared to RAID 0 or RAID 1. There is more computing overhead to stripe data across drives in a 3+ drive RAID array. You take a hit on writing data.

 

And as Ted B mentions, RAID should never be considered a method of backup.

(Amusement) RAID5 and RAID10 is no faster than RAID0 or RAID1? Perhaps in some limited cases, but that is not the case in most real world applications. RAID5 or better can, of course, simultaneously read or write to multiple drives, and that can vastly increase performance.

The part that alludes to the higher RAID levels needing extra processing is true, but only becomes a significant factor when the RAID processor is weak and/or not dedicated to the device.

Certainly, the more spinning platters and heads you have, the more potential for performance. You are welcome to dispute that, but I think that most of the cases where you can dispute are in cases like this, where RAID1 has been designed into the product for high availability. And because it has to write the data twice, it is going to be quite a bit slower at writing data than at reading.

All in all, I think Chris found a very good balance point in his design between performance and cost.

-Paul

(Amusement) RAID5 and RAID10 is no faster than RAID0 or RAID1? Perhaps in some limited cases, but that is not the case in most real world applications. RAID5 or better can, of course, simultaneously read or write to multiple drives, and that can vastly increase performance.

 

The part that alludes to the higher RAID levels needing extra processing is true, but only becomes a significant factor when the RAID processor is weak and/or not dedicated to the device.

 

Certainly, the more spinning platters and heads you have, the more potential for performance. You are welcome to dispute that, but I think that most of the cases where you can dispute are in cases like this, where RAID1 has been designed into the product for high availability. And because it has to write the data twice, it is going to be quite a bit slower at writing data than at reading.

 

All in all, I think Chris found a very good balance point in his design between performance and cost.

 

-Paul

Everything I am reading about RAID 5 says it's slower than RAID 0. I did err in including RAID 1 in my first comment.

TV

Dropbox Pro is a nice offsite backup option if your data is not too large. It's less than $100 a year for 1TB, and lan sync is nice for maintaining copies on multiple local machines.

And a 1TB USB hard drive is only $65, backup options are too cheap to not do it.

Everything I am reading about RAID 5 says it's slower than RAID 0. I did err in including RAID 1 in my first comment.

 

TV

RAID0 can be fast, no fooling. But striping across disks can be good or bad, deprding uon the application. In it's most basic formst, RAID0 stripes can iterally be an entire disk, not a lot of advantage.

And it is a matter of scale. The larger the scale, the less practical RAID0 becomes. The smaller the scale, the better. But RAID0 maes your data more susceptable to loss, while higher RAID levels support high availability and usually, better perforance. With really good SANs costing about the same as a good DAC these days, well, Who knows what might come up?

Again, I think the choice of RAID1 for Chris' CAPS Serve is a good idea. High Availability.

Is the Win Server 2012 r2 license limited to "per machine" as usual, meaning if the particular TS140 breaks, the Win Server cannot be resintalled on another machine?

Hi Jon

To be honest I am not sure - it is a ROK license so I suspect that there are significant restrictions.

Thanks

Paul

Chris - nice write up and info. The application for this setup is pretty specific and obvious and I'm not sure why the merits of this build would be questioned. This is one of many possible solutions designed to meet a specific need.

Its funny - when I purchased my NAS I was using many of the built in functions (apps). Now, I ave pretty much disabled all of them as I have no use for "media server, iTunes server, movie streaming" etc... I only use it as a network drive (file server) for music and data storage.

I have a similar PC Server build, soon to be upgraded to a Xeon processor. It contains about 8tb of music. I use Windows Server 2012 R2 for the operating system. I already use Windows 2012 r2 on my single audio PC. Also installed is jPlay and AudiophileOptimizer. That combo sounds great on my Audio PC. Next I decided to install AO on the the Server PC to see if it would make a difference. It took just a few minutes of listening to find that using AudiophileOptimizer on the server made just as large a difference there as on the audio PC. The effect of two installations of AudiophileOptimizer is better than one. It does give one many more options to play with though.

As as a result I believe a linear pus added to the server build would seem to be a no brainier. Can't wait to try it.

Come on SANTA find me some money!

Next on the horizon the jPlay two PC concept.

What fun!

For the record, slickdeals has newegg running a deal on the TS140 Xeon for 275 bucks after rebate w/ free shipping. Hard to pass up on this one if you need a server box.

Hi Chris,

Have you ever found a difference in noise floor or fatiguing between using this Cortes build as a DLNA server, or DLNA server/ controller with JRiver and MinimServer on a NAS?

Chris- When is the next CAPS 4 model going to be revealed?