[wplug] Linux software RAID

[Drew from Zhrodague]

> I have a friend with a RAID 1 (mirroring) and a drive that's dying.
>
> I went to yank the drive and tried to add another, but the system
> wouldn't boot.  I then added the extra drive as a third disk in the
> SCSI chain and booted.  Then I tried to remove the second drive
> using some instructions with mdadm, but the system refused to
> remove the drive.  Something about resources inaccessible or
> something.
>
> I have a set of other instructions discussing raidhotadd, but
> that utility isn't in the system.  A guess of
> "yum install raidtools" didn't help either.  So before I spend
> an hour looking around ftp sites and blogs, can anyone tell
> me what package I need for this utility?

 	Raidtools might be old, I forget.

 	I have this problem in my host where one of the disks dies (under 
extremely heavy use). I have to --fail, --remove, and then --add the 
device. That fixes it until it dies again.

 	As far as replacing one of the drives, I'd recommend to put an 
identical partition table on it, as well as the bootloader, and then see 
if you can use mdadm to sync the disks (--add /dev/sdx1). You can cat 
/proc/mdstat to give you more information, and it will even tell you how 
long it will take to rebuild.

 		Good luck!


-- 

Drew from Zhrodague		http://www.WiFiMaps.com
drew at zhrodague.net		http://www.zhrodague.net