diff options
author | NeilBrown <neilb@suse.de> | 2006-03-27 09:18:10 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-27 16:45:01 (GMT) |
commit | 292695531ae4019bb15deedc121b218d1908b648 (patch) | |
tree | fb205eae13c3f3410f6ea44557b1c96b075a4d44 /drivers/md/Kconfig | |
parent | ccfcc3c10b2a5cb8fd3c918199a4ff904fc6fb3e (diff) | |
download | linux-292695531ae4019bb15deedc121b218d1908b648.tar.xz |
[PATCH] md: Final stages of raid5 expand code
This patch adds raid5_reshape and end_reshape which will start and finish the
reshape processes.
raid5_reshape is only enabled in CONFIG_MD_RAID5_RESHAPE is set, to discourage
accidental use.
Read the 'help' for the CONFIG_MD_RAID5_RESHAPE entry.
and Make sure that you have backups, just in case.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/md/Kconfig')
-rw-r--r-- | drivers/md/Kconfig | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index ac43f98..fd2aae1 100644 --- a/drivers/md/Kconfig +++ b/drivers/md/Kconfig @@ -127,6 +127,32 @@ config MD_RAID5 If unsure, say Y. +config MD_RAID5_RESHAPE + bool "Support adding drives to a raid-5 array (experimental)" + depends on MD_RAID5 && EXPERIMENTAL + ---help--- + A RAID-5 set can be expanded by adding extra drives. This + requires "restriping" the array which means (almost) every + block must be written to a different place. + + This option allows such restriping to be done while the array + is online. However it is still EXPERIMENTAL code. It should + work, but please be sure that you have backups. + + You will need a version of mdadm newer than 2.3.1. During the + early stage of reshape there is a critical section where live data + is being over-written. A crash during this time needs extra care + for recovery. The newer mdadm takes a copy of the data in the + critical section and will restore it, if necessary, after a crash. + + The mdadm usage is e.g. + mdadm --grow /dev/md1 --raid-disks=6 + to grow '/dev/md1' to having 6 disks. + + Note: The array can only be expanded, not contracted. + There should be enough spares already present to make the new + array workable. + config MD_RAID6 tristate "RAID-6 mode" depends on BLK_DEV_MD |