Expandable RAID 5?

good to know about linux then, that could come in handy for a back up server i have at work, as we have a adaptec raid card in it but the performance is pure crap!

Linux software raid

Becareful of WHS. There are reports of data corruption, but it is not intended for enterprise environments.

There is a much better solution called ZFS that runs on open solaris (and linux through fuse). It works on a JBOD level like a very sophisticated WHS with raid, backup, imaging, data integrity. This is the BEST solution for a NAS. Check wikipedia for some basic info and some links to the project site.

I'm building a linux based NAS/mediacenter and am very interested in software raid. It has better performance than hardware raid (raid controller) in the raid 10 implementation I'm going to use. You can still partition your drives any way you want. For example; on each 1tb drive you do 1x 10 gb, 1x 989 gb, and 1x 1gb partition. Then use software raid 5/6 on the big partition, raid 1(+0) on the 10 gb for OS, and raid 0 for swap in the 1gb partition. The os figures it all out with only a small penalty in cpu and memory i/o. You won't find any controller cards that can do that!

The WHS server corruption issues have long been rectified. Nope it certainly is not intended for enterprise enviroments, that is why it is called windows home server.

I would be very careful calling any server software the best. Different users have different requirements. For a simple, reliable, easy to set-up package WHS is very nice. It ia meant for storage, not high I/O. I would put FreeNAS right there with it. I only went with WHS due to the easier expandability. WHS and FreeNAS could both be set-up by most average users. WHS is certainly not without its faults. It uses a goofy storage method that while, effective, is horribly energy inefficient during writes.

From a quick look ZFS could not. ZFS looks like it could be a very nice set-up but I would not call it the best. Different strokes for different folks.

for me server software would have more potential to mess up, since it has more to deal with, the OS, and all other OS tasks, a hardware raid card is coded for what it does and only that and is done with, no extra, bells and whistles, why they cost so much and are used through out the world in massive enterprise systems, and not so much "linux" OS on a normal system.

karkas said:

So these controllers are capable of expanding the RAID's size without moving all data & rebuilding that array? Honestly, if the array falls apart I'm not too worried, because I'll be backing up with carbonite.... and while that kind of data won't be fast to DL back, it is at least safe.

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noegruts said:

Nobody has yet answered your question. The feature you are looking for is called "Online Capacity Expansion" or OLCE. If you find a RAID card with this feature, it will allow you to dynamically expand the array.

No motherboard RAID currently supports this feature, as far as I am aware.

Click to expand...

I've just gone from an ICH8R RAID5 to ICH8R RAID5 - comes up straight away with no problems, then added an additional drive into the array (making 5 * 500gb) no problem - takes about 24 hours to perform the 'RAID migration' - the additional disk into the array under VISTAx64 then re-boot and the extra space is there.

Thanks