Difference between MS's Drive Extender and JBOD in a NAS?

[Bizarroterl]

Originally Posted by panteragstk

I've been doing a lot of thinking on this exact subject. I like the idea of how unRAID does things. I was really looking into a RAID 5 or 6 setup, but after doing some research I've found that one issue people seem to have is not when the drive dies, but when the RAID card dies. Example: if I purchase a high end areca card with 24 ports and have a RAID 6 array and the card dies I have to find the exact same card or my array is useless. I could be wrong about that and I'd really like to know if that is the case.

There is no standard for how a manufacturer/raid card organizes the data on the drives. 2 Arrays may be the same type (RAID5/6/10) yet be totally incompatible. This can be the case even between different firmware levels on the exact same card.

The only way to know for sure is to contact the manufacturer. Even then you could be surprised. To be absolutely sure you could buy 2 identical cards, but that could be expensive when you're looking at cards that allow expansion.

[stanger89]

I know 3ware was always backward compatible. Newer cards supported arrays built on different or older models (of 3ware cards).

[Spectrum]

Originally Posted by panteragstk

I've been doing a lot of thinking on this exact subject. I like the idea of how unRAID does things. I was really looking into a RAID 5 or 6 setup, but after doing some research I've found that one issue people seem to have is not when the drive dies, but when the RAID card dies. Example: if I purchase a high end areca card with 24 ports and have a RAID 6 array and the card dies I have to find the exact same card or my array is useless. I could be wrong about that and I'd really like to know if that is the case.

That's pretty much it. Sometimes you can get by with a card that has the same chipset and many manufacturers make cards that are backwards compatible, but don't count on that being the case; do your homework and make sure you have a contingency plan before disaster strikes!

[panteragstk]

Originally Posted by Bizarroterl

There is no standard for how a manufacturer/raid card organizes the data on the drives. 2 Arrays may be the same type (RAID5/6/10) yet be totally incompatible. This can be the case even between different firmware levels on the exact same card.

The only way to know for sure is to contact the manufacturer. Even then you could be surprised. To be absolutely sure you could buy 2 identical cards, but that could be expensive when you're looking at cards that allow expansion.

Originally Posted by stanger89

I know 3ware was always backward compatible. Newer cards supported arrays built on different or older models (of 3ware cards).

Originally Posted by Spectrum

That's pretty much it. Sometimes you can get by with a card that has the same chipset and many manufacturers make cards that are backwards compatible, but don't count on that being the case; do your homework and make sure you have a contingency plan before disaster strikes!

Thanks for the clarification. That is the main thing keeping me from going the hardware raid route. I've had raid cards die on me more often than the actual drives. That would be why I won't be purchasing anything made by promise again. This isn't an easy decision is it?