[krassyg]

I need to organize 16-20 drives into a software RAID 5. I am getting these enclosures:

http://www.triumphtech.com/@PRDCT/TT735.htm


Is it worth it getting the 1394b over the 1394a version? It would cost me more than double. The RAID would be used only for DVD storage.

 

[krassyg]

bump

 

[adamf]

Krassyg,

I'm not sure how much the b over a gets you (besides the listed bump in speeds). Much of the limitation may be in the ATA controller to the firewire handoff, no? I'm running a Raid 0 over my network and can play things just fine across a 100 MBps connection ethernet cable. If it was for storage only, I might save the costs (ie stay with a) and get bigger drives in my mind, unless someone really says the one time you write the drive (ie copy) m akes up the cost difference. Let me know how it turns out as I'm thinking of moving to a RAID 5 as my RAID 0 is making me nervous after a windows xp driver crashed and took down the whole array while I repaired it.


Adam

 

[greenkiwi]

Are there any issues with running a RAID with external disks that can be disconnected at any point? I have 4 FW drives that I've been thinking about using RAID for, but haven't because I didn't know whether it would work. And whether there would be any problems as drives could potentially get disconnected.


kiwi

 

[jehrico76]

Instead of one monster array with all of those drives, how about one array with 2-5 drives with the faster drives, and another (or 2 or 3) with the slower drives. If you need the faster throughput, use the fast one, and when you're done, move the data to the slow one to open it back up. Then it would only cost you a little bit more, if you really had a need for the extra bandwidth.

 

[krassyg]

Quote:

Originally posted by adamf Krassyg, I'm not sure how much the b over a gets you (besides the listed bump in speeds). Much of the limitation may be in the ATA controller to the firewire handoff, no? I'm running a Raid 0 over my network and can play things just fine across a 100 MBps connection ethernet cable. If it was for storage only, I might save the costs (ie stay with a) and get bigger drives in my mind, unless someone really says the one time you write the drive (ie copy) m akes up the cost difference. Let me know how it turns out as I'm thinking of moving to a RAID 5 as my RAID 0 is making me nervous after a windows xp driver crashed and took down the whole array while I repaired it. Adam

Adam,


Where you running software RAID 0 or hardware RAID 0?

 

[krassyg]

I also found these enclosures that have a version for 1394B only, hopefully they will be about $30-40:

http://www.welland.com.tw/html/case/x40.html

 

[AV_Spyder]

are you going to be accessing the DVDs over a 100Mb network? If so, firewire speed is fairly irrelevant as your bottleneck will be the network.

What size drives are you planning on using?

 

[Mr.Poindexter]

External drive enclosure that can disconnect are not a problem for RAID arrays. The upper end RAID hardware controllers allow hot swapping, which is basically what you get with USB and Firewire.


I cannot see how you would need 1394b, as the 1394a is already fast enough to handle over a dozen HD streams.

 

[krassyg]

Since I am buying these for the long run, I would rather get the 1394b, just in case. I might even buy 30 plus, in case I run out of space in a few years.

 

[adamf]

Kiwi,

I may not understand the question but I don't think you can disconnect 1 drive (of 2 for example) in a software RAID 0 configuration (I think you would need a stripped array or other data redundancy to allow a hot swap but defer to others with more experience). You can disconnect all the drives on "an array" as suggested above but if both drives aren't accessible at the same time, the array will fail since only half the data is available. RAID 1 I'm not sure what would happen as it is mirroring the other drive and I am not familiar enough with an external software based solution as opposed to a typical Hot swapping hardware-based solution which might allow this.


PS: In the FWIW" department, LaCie has announced "the big one." 1 terrabyte of HD storage in a single external unit for about $1200. Actually not a bad price for this much storage compared with the time and effort of buying 4, 250Gb drives, cards, time to set up, etc. details at:
http://www.lacie.com/products/product.htm?id=10118

 

[loftus]

Doesn't the speed advantage of raid 5 come from accessing multiple blocks of data off different drives simultaneously? Unless you have 1 firewire channel per drive you are going to be daisy chaining the drives - so can firewire cope with transfers from multiple devices simultaneously? I don't know, but even if it does, it will limit your throughput as the number of drives scales upward.


If you only want Raid5 for data reduncency then the speed issue may not be important, as long as it meets some minimum spec. I'd recommend 1394b to be safe


I would be interested to hear how it works for you

 

[greenkiwi]

Adam,


My question was just one of reliability, as I've had some issues with external firewire drives. Right now, I have drives in a 4 bay unit, with two firewire controllers (2 drives per controller). This works most of the time, but at times, drives get reordered or every so often they have issues and don't connect. (I'm running WinXP Pro SP1.) I am interested in this, as it seems like a reasonable way to put together a raid, allowing for hot swapping of bad devices, etc. (though, I would want to connect each drive up to a FW hub or card individually so that I didn't have daisy chaining issues, with one drive taking down the rest.


My concern would be with one or more drives having issues and the RAID array becoming corrupted. Similarly, with how the device structure works, and whether you can be assured that the drives will be ordered in the same manner (or if that even matters.)


Of note, here's a FW 800 RAID device:
http://www.firewiredirect.com/firewi.../RAIDHSB.shtml


It only does RAID 0 or 1, but it's a start.


kiwi

 

[greenkiwi]

One other qustion with the LaCie drive is that it seems to have only a 1 year warranty. It would be a real shame for it to die 1.5 years out and be unusable. Does anyone know whether there are extended warranties that can be purchased for it? Like CompUSA's TAP? And/or whether it can be reused with new harddrives?

 

[skriefal]

The 1TB Lacie drive is interesting, but I've been unable to find any information about the noise levels produced by the drive. Are they packing 4 drives into that case? If so, any ideas of which drives they're using? If they're Western Digital drives, then I'd expect the idle whine from 4 WD drives to be unbearable... at least to me. If they're Maxtor or Hitachi drives with fluid bearings, then the noise might at least be tolerable.

 

[greenkiwi]

I have a couple emails into their sales/support people. If they respond, I'll add those questions on.


kiwi

 

[greenkiwi]

The other interesting system that they had was their "Ethernet Drive" It's basically a NAS, but it has the very nice feature of being able to connect a USB or FW drive onto it and increasing its available storage.

http://www.lacie.com/products/product.htm?id=10073


It doesn't look like it provides RAID or anything, but it does look like it has some nice features.


kiwi

 

[apnar]

Quote:

Originally posted by greenkiwi My question was just one of reliability, as I've had some issues with external firewire drives. Right now, I have drives in a 4 bay unit, with two firewire controllers (2 drives per controller). This works most of the time, but at times, drives get reordered or every so often they have issues and don't connect. (I'm running WinXP Pro SP1.) I am interested in this, as it seems like a reasonable way to put together a raid, allowing for hot swapping of bad devices, etc. (though, I would want to connect each drive up to a FW hub or card individually so that I didn't have daisy chaining issues, with one drive taking down the rest.

kiwi,


You may want to try upgrading your disks from basic to dynamic (which you can do in disk manager). I don't know for sure but I think that dynamic disks remember where they are mounted or which raid they are a part of even if they are reordered.


-apnar

 

[apnar]

sorry just did some reading and it seems that dynamic disks may not be available for firewire drives, as referenced here:

http://support.microsoft.com/?kbid=254105

 

[astro11]

What about:

http://support.microsoft.com/default...b;en-us;299598


Krassyg, what solution did you end up using?