Is raid needed for a media (sage) server?

[Konig]

I'm getting ready to build a server with 2-3 tuners and 500 to 750GB of storage. It will record sage and stream recorded shows, DVDs, MP3s, and photos to three clients over a 100mbps wired network. It will not used as a workstation-just as a server.

Would it be necessary for me to build a Raid Array in to this system? If so, then what kind of array? Raid 5?

Now that SageV3 is out and Hi-Def recording is a viable option how would the system requirements change?

Thanks, Konig

[ke6guj]

It's not necessary to go RAID, only if you want to. The deciding factor is, are you willing to deal with the loss of some recorded shows or other data if a drive failed?

If not, then go RAID. IMO, RAID 5 would be the best, since you only lose 1 drive for RAID purposes. For example, in a 4-drive array would use 3 drives for storage, and the 4th would be used to maintain the RAID parity. RAID 0 has no redunancy, RAID 1 is not cost effective since you loose half your drives for RAID parity.

[stanger89]

For me, RAID seems to be a logical choice once you get beyond 2-3 drives. Beyond that it can be quite beneficial, that or less, and the benefits are hard to balance against the increased cost.

[teedublu]

RAID does not protect against "soft" or human failures.
I think daily sync-backup during the early morning is a better backup approach. Drives will fail, and RAID is ideal for a "clean" hard drive failure. But, sometimes that failing drive will start to go lame and mess up data, which the RAID dutifully replicates.
Don't forget to do at least daily backups with at least a 1 week rotation of your wiz.bak and sage.properties.autobackup (you can backup the "live" files too wiz.bin and sage.properties, but, IMHO, that's not necessary and not good to be making a copy of a file that's open/being written to). You restore those files while sage isn't running by overwriting the wiz.bin with wiz.bak etc.

SyncBack is an excellent and free file-sync backup program that works well for sync-backing the video dir to your backup drive.
You can use windows backup program to schedule backups of wiz.bak etc. There are some posts on that subject on the forum. There is also a batch file posted, which you can have the scheduler run. The nice thing about the batch approach is it's simple to implement and it's easy to restore a file.

TW

[Blue]

I agree about SyncBack - it's a great little free program.

However, I'm questioning now whether RAID 5 is worthwhile, because recently an expansion of my array failed, resulting in a loss of all data. This was due to a software failure during the expansion.

RAID 5 is not a substitute for backups. I would probably only recommend RAID 5 if you're concerned about being 100% up and running if/when a drive fails. If that doesn't matter to you, then maybe RAID 5 isn't the best fit.

Regardless of the solution, when a drive fails it will need replacement. And you should always have backups of your media.

[Konig]

My main concern isn't data backup. I'll back up the critical data on other systems or onto DVDs.

My main concern with the with the server is whether it will be able to keep up with the data load of recording upto 3 shows to the hard drives while streaming 3 archived shows at the same time.

Will this system, with 3-4 hard drives, be any faster and will the data load I plan for the system require the speed gained by raid?

Thanks, Konig

[stanger89]

Originally Posted by teedublu

RAID does not protect against "soft" or human failures.
I think daily sync-backup during the early morning is a better backup approach. Drives will fail, and RAID is ideal for a "clean" hard drive failure. But, sometimes that failing drive will start to go lame and mess up data, which the RAID dutifully replicates.

But we aren't talking about RAID for the OS, SageTV install, datafiles type stuff (that is small and easilly backed up onto a single DVD).

What we are talking about RAID for is the huge media server stuff. 1TB of media is basically impractical to backup. Anything beyond 2 or so HDDs is that way.

Konig, 1 HDD can keep up with many recordings, we're talking a max 1.5MB/sec recording and HDDs that routinely do 40-60MB/sec. You don't go RAID for speed in a media server. You use RAID for simplicity/efficiency of storage (one, single "drive") and redundancy.

[Konig]

Stanger, raid doesn't perform faster? Ok. Hey, by the way, I'm originally from Cedar Falls, IA. Small world, eh?

I've heard of disk spanning. That would make all the drives appear like one. I wouldn't be able to rebuild if one craps out, but it would be simple and I wouldn't need any more hardware, right?

[stanger89]

Originally Posted by Konig

Stanger, raid doesn't perform faster? Ok. Hey, by the way, I'm originally from Cedar Falls, IA. Small world, eh?

Well it can (I'm not going to categorically state it does, but usually it will be faster), but my point was that you don't need the speed. Even HD is only 2MB/sec.

I've heard of disk spanning. That would make all the drives appear like one. I wouldn't be able to rebuild if one craps out, but it would be simple and I wouldn't need any more hardware, right?

I've also heard that with a spanned "array" if one drive dies, it takes out the whole array. If you're going to build any sort of array, I'd go RAID-5 and get a good controller. Otherwise I would just go JBOD. Sage abstracts the "complexities" of multiple drive letters so the benefit of a single array there is less.

Honestly with the capacities you're talking about I'd just go with 2 400-500GB HDDs and do nothing special with them.

[Blue]

On my RAID 5 array I noticed playback problems while I'm ripping a DVD to the array. Specifically, ripping with DVD Decrypter (on the server) while playing back an xvid (located on the server) with TheaterTek on the HTPC. There are some minor hesitations during playback, but it's tolerable.

I'd question whether recording 3 shows while playing back 3 shows would be doable, but then again, I've never tried it.

[Konig]

I guess I'll start with 2 tuners and 2 drives and increase them one at a time to see how the performance is. If I see too much load on one drive that causes performance issues, then I'll try a raid array to split the load more evenly. But it sounds like there shouldn't be any issues at 2MB/sec.

Would a server like this see much benefit from a dual core processor or a dual CPU system? what about 64bit vs. 32bit CPUs?

[stanger89]

Originally Posted by Konig

I guess I'll start with 2 tuners and 2 drives and increase them one at a time to see how the performance is. If I see too much load on one drive that causes performance issues, then I'll try a raid array to split the load more evenly. But it sounds like there shouldn't be any issues at 2MB/sec.

Just decide now if you want to go RAID or not. If you start without a RAID card, or without one with OCE, then later you can't create (or add drives to) an array without destroying the data on the current drives.

Would a server like this see much benefit from a dual core processor or a dual CPU system? what about 64bit vs. 32bit CPUs?

No, the CPU load for a SageTV server is minimal.

[stanger89]

Originally Posted by Blue

On my RAID 5 array I noticed playback problems while I'm ripping a DVD to the array. Specifically, ripping with DVD Decrypter (on the server) while playing back an xvid (located on the server) with TheaterTek on the HTPC. There are some minor hesitations during playback, but it's tolerable.

What's your hardware config? RAID controller?

[Blue]

Well, this isn't really Sage related, but...

The server is a P4 3.0, 1 GB PC3200, Adaptec 2810SA, DiamondMax10 300 GB drives on the array (64K stripe), WD Raptor for the OS, 9800 Pro. The HTPC is connected via CAT5e (100 Mbps) through a NetGear router, and has a P4 2.8, 512 MB PC3200, WD Raptor for the OS, 6600GT.

[dagar]

Wow, I can't believe some storage noob (RAID fanboy?) didn't suggest using RAID 0

The other thing to consider, for simplicity, is that Sage has a very graceful mechanism for using/displaying your many drives in a seamless manner. You could just throw drives in as seperate partitions and be done. Unless you want some redundancy