It turns out (not mentioned there) that 7 disks is the best number for a RAID 5, as you loose exactly one (hmm perhaps two, I can't remember) disk(s) to the error correction info.
Thanks for the link... it'll take me a few to grok the whole concept... but I'm getting there. Either way, there "could" be a way for me to use this RAID for my needs... correct...?
Stupid question #12: How would it connect to my Mac... FireWire...?
There's a thing I missed somehow: swappable power supplies. Do they appear in Xserve RAID only or also in Xserve we've seen? It's certainly good to have redundant power supplies to protect your RAID, but in some critical applications it's critical to have your server on and running 24/7. Without rebooting.
Has anyone noticed pluggable power supplies in the Xserve?
<strong>The big question for me is... would I be able to use that product with my G4 to serve-up video & audio if it were striped...?
My "understanding" (which may be wrong) of the configuration is that there are 14 drives... 2 banks of 7, each bank of 7 gets striped together and they mirror each-other, so it's essentially a RAID of 7 drives with another 7 to be a back-up.
If one drive goes... am I hosed with ALL of my data within that bank of 7...? (ignoring the back-up mirror)
- Scott</strong><hr></blockquote>
raid 0 (stripe): it's fast but if one drive goes, your data is gone.
raid 1 (mirror): as fast as the single disk but redundant. means also that you have half the capacity: 2x60 GB disks in raid1 config = 60GB free space)
raid 1+0 (or 10): (stripe + mirror): fast & redundant! great thing. you need at least 4 disks for this config. so it's not cheap
raid 5 (stripe with parity disk): at least three disks. one will be parity for reconstruction of the broken one. IMHO performance is better with raid 1+0. raid 5 needs computing time for the parity data. once i changed a very busy mail system from raid5 to 1+0: the performance improvement was incredible...
MAN! Do I need to do some homework, or WHAT...!!!??? All I got from that was "Blah blah blah blah RAID blah blah DV blah Audio blah blah blah performance blah blah..."
Thanx anyhow.</strong><hr></blockquote>
Dude sorry. I read my post and it was as clear as mud. Posted that at 6am so brain had not fully warmed up and engaged LOL
<strong>If I remember correctly from my networking classes desn't hard drive life decrease when the drives are stored and run vertically? I LOVE the design of the RAID but every time I have had a vertical HD it has died like 5 times faster than my horizontal ones.
Mac Guru</strong><hr></blockquote>
Shouldn't be a problem. Sun Hardware Raids (StoreEdge) and NetApp Filers have their drives stored vertically and they ARE mission critical systems. Okay, they get class A drives from manufacturers, not the class B or C drive out in the stores. That maybe makes the difference.
I believe that vertically mounted drives make for much better cooling too. It you stack drives on top of each other, you need a lot of air blowing through to keep the heat from one drive from smoking the drive(s) above it. Therefore the air must move between all the drives With vertically mounted drives, you are mostly concerned with air flowing along the top of the case and out, collecting the hot air and driving it out before it builds up. When you look at the xServe RAID, the drives are all packed together, and the only air vents on the front are at the top. With horizontal drives, I think you'd need vents between every drive, cluttering up the look and reducing the density you pack them in.
The simple answer is do not run RAID 0, for DV and Audio your performance would be fine running RAID 5 or a Combo of Levels(ie 0 +1)</strong><hr></blockquote>
I had heard that RAID 5 was not recommended for video. I was told that the calculation was too expensive for that application and to simply stick to striping (or 1+0). I personally love RAID 5, but use it for fileserving/database serving. Very cool technology!
I had heard that RAID 5 was not recommended for video. I was told that the calculation was too expensive for that application and to simply stick to striping (or 1+0). I personally love RAID 5, but use it for fileserving/database serving. Very cool technology!</strong><hr></blockquote>
We have a 400 GB RAID 5 FiberChannel storage system that is shared between 3 video editing suites, and it works really well.
Does anyone know if disk utility can do raid 1+0? I know it can do mirroring and striping individually but can it do both at once? It?s cool that apple made it so the Xserve could boot off of its software raid. Hopefully this trickles down to OS X client.
<strong>Does anyone know if disk utility can do raid 1+0? I know it can do mirroring and striping individually but can it do both at once? It’s cool that apple made it so the Xserve could boot off of its software raid. Hopefully this trickles down to OS X client.</strong><hr></blockquote>
I don't know if disk utility can do this, but software raid under unix usually works like this:
First you configure the two stripes. For each stripe you get a new device name. Then you mirror both stripe devices.
Maybe it's similar, but I admit: I never used raid on macs ;-( .... once I will)
Comments
<strong>A primer on <a href="http://www.megahaus.com/tech/RAIDbasics.shtml"; target="_blank">RAID</a>.
It turns out (not mentioned there) that 7 disks is the best number for a RAID 5, as you loose exactly one (hmm perhaps two, I can't remember) disk(s) to the error correction info.
[ 05-15-2002: Message edited by: *l++ ]</strong><hr></blockquote>
Thanks for the link... it'll take me a few to grok the whole concept... but I'm getting there. Either way, there "could" be a way for me to use this RAID for my needs... correct...?
Stupid question #12: How would it connect to my Mac... FireWire...?
Has anyone noticed pluggable power supplies in the Xserve?
<strong>The big question for me is... would I be able to use that product with my G4 to serve-up video & audio if it were striped...?
My "understanding" (which may be wrong) of the configuration is that there are 14 drives... 2 banks of 7, each bank of 7 gets striped together and they mirror each-other, so it's essentially a RAID of 7 drives with another 7 to be a back-up.
If one drive goes... am I hosed with ALL of my data within that bank of 7...? (ignoring the back-up mirror)
- Scott</strong><hr></blockquote>
raid 0 (stripe): it's fast but if one drive goes, your data is gone.
raid 1 (mirror): as fast as the single disk but redundant. means also that you have half the capacity: 2x60 GB disks in raid1 config = 60GB free space)
raid 1+0 (or 10): (stripe + mirror): fast & redundant! great thing. you need at least 4 disks for this config. so it's not cheap
raid 5 (stripe with parity disk): at least three disks. one will be parity for reconstruction of the broken one. IMHO performance is better with raid 1+0. raid 5 needs computing time for the parity data. once i changed a very busy mail system from raid5 to 1+0: the performance improvement was incredible...
cheers
zero
<strong>
MAN! Do I need to do some homework, or WHAT...!!!??? All I got from that was "Blah blah blah blah RAID blah blah DV blah Audio blah blah blah performance blah blah..."
Thanx anyhow.</strong><hr></blockquote>
Dude sorry. I read my post and it was as clear as mud. Posted that at 6am so brain had not fully warmed up and engaged LOL
<strong>If I remember correctly from my networking classes desn't hard drive life decrease when the drives are stored and run vertically? I LOVE the design of the RAID but every time I have had a vertical HD it has died like 5 times faster than my horizontal ones.
Mac Guru</strong><hr></blockquote>
Shouldn't be a problem. Sun Hardware Raids (StoreEdge) and NetApp Filers have their drives stored vertically and they ARE mission critical systems. Okay, they get class A drives from manufacturers, not the class B or C drive out in the stores. That maybe makes the difference.
zero
Are the RAID drives the SAME drives as in the Xserve unit...? (Interchangeable...?)
---
The Apple Drive Units in Xserve and Xserve RAID are the same.
<strong>Xserve RAID has redundant PSes, but not Xserve.
---
The Apple Drive Units in Xserve and Xserve RAID are the same.</strong><hr></blockquote>
How could they be? The Drives in the Xserve are IDE and the ones in the Raid box are SCSI right? Or am I missing something here?
<strong>
The simple answer is do not run RAID 0, for DV and Audio your performance would be fine running RAID 5 or a Combo of Levels(ie 0 +1)</strong><hr></blockquote>
I had heard that RAID 5 was not recommended for video. I was told that the calculation was too expensive for that application and to simply stick to striping (or 1+0). I personally love RAID 5, but use it for fileserving/database serving. Very cool technology!
I don't think this is much of an issue with spindle synchronized drives and hardware parity computations.
<strong>
I had heard that RAID 5 was not recommended for video. I was told that the calculation was too expensive for that application and to simply stick to striping (or 1+0). I personally love RAID 5, but use it for fileserving/database serving. Very cool technology!</strong><hr></blockquote>
We have a 400 GB RAID 5 FiberChannel storage system that is shared between 3 video editing suites, and it works really well.
<strong>Xserve and Xserve RAID both use IDE HDDs.</strong><hr></blockquote>
Really? Well that should keep the cost way down.
14 x $500 = ouch
Apple may find itself selling a lot of sled "replacements" instead of complete modules.
<strong>Does anyone know if disk utility can do raid 1+0? I know it can do mirroring and striping individually but can it do both at once? It’s cool that apple made it so the Xserve could boot off of its software raid. Hopefully this trickles down to OS X client.</strong><hr></blockquote>
I don't know if disk utility can do this, but software raid under unix usually works like this:
First you configure the two stripes. For each stripe you get a new device name. Then you mirror both stripe devices.
Maybe it's similar, but I admit: I never used raid on macs ;-( .... once I will)
<strong>I don't know. Apple sells 120 GB modules for $500...
14 x $500 = ouch
Apple may find itself selling a lot of sled "replacements" instead of complete modules.</strong><hr></blockquote>
If the Xraid will cost $7,000 it will be cheap. I haven't seen any other RAID systems at that price (yes I have, but that uses 5400rpm drives).
A Snap Server 12000 with 960 GB storage costs $15,000.
<strong>
If the Xraid will cost $7,000 it will be cheap. I haven't seen any other RAID systems at that price (yes I have, but that uses 5400rpm drives).
A Snap Server 12000 with 960 GB storage costs $15,000.</strong><hr></blockquote>
I am guessing fully decked out, 9,000 to 10,000 dollars
[ 05-16-2002: Message edited by: unknown_source ]</p>
<strong>
I am guessing fully decked out, 9,000 to 10,000 dollars
[ 05-16-2002: Message edited by: unknown_source ]</strong><hr></blockquote>
Who needs to guess...? I just went and configured one at the Apple Store as such:
Xserve Dual 1GHz
120GB Ultra ATA - 7200rpm - Bay 1 \t065-3315
Gigabit Fiber Ethernet Card \t065-3561
ATI Graphics Card \t065-3625
120GB Ultra ATA - 7200rpm - Bay 4 \t065-3551
120GB Ultra ATA - 7200rpm - Bay 3 \t065-3550
120GB Ultra ATA - 7200rpm - Bay 2 \t065-3545
Gigabit Ethernet Card \t065-3416
Accessory kit \t065-3300
CD-ROM drive \t065-3316
Dual 1GHz PowerPC G4 \t065-3319
Mac OS X Server, Unlimited License \t065-3301
2GB DDR SDRAM - 4 DIMMs \t065-3544
Grand Total: $7,449.00 (no service plan)