Btrfs merged for 2.6.29 [LWN.net]

Btrfs merged for 2.6.29

Posted Jan 12, 2009 9:23 UTC (Mon) by hensema (guest, #980)
In reply to: Btrfs merged for 2.6.29 by Duncan
Parent article: Btrfs merged for 2.6.29

The Linux md code probably isn't going to be use by any raid vendor anytime soon. It just lacks features needed in serious raid systems, such as online raid level migration and (good?) support for hot swappable disks.

Also, support for battery backed write-through cache may or may not be needed at the md/raid level, I don't know.

Anyway, the linux md disk format may or may not be suitable to raid vendors to use on disks. The linux md code may or may not be suitable to be used in hardware raid implementations.

I think it's highly unlikely linux md code will find its way into hardware raid implementations.

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Btrfs merged for 2.6.29

Posted Jan 12, 2009 10:08 UTC (Mon) by dlang (✭ supporter ✭, #313) [Link]

the fact that the linux raid code isn't suitable for most raid hardware is true, but I disagree with the rest of your points.

most 'hardware' raid cards don't support raid level migration, in fact most don't even support raid resizing (wihc MD does support)

MD does support swapping disks (it doesn't do it automagicly, but you can remove and replace drives in a MD array just fine)

I would be surprised to see linux running on a raid card.

but I would not be surprised to see linux running on a external raid box. the type of thing that allows you to connect a bunch of SATA drives to it and exports the results as a single drive via SCSI or FC.

for this to work well the target mode will need to get into the kernel and get well tested first.