[ale] Software RAID1 rebuild after HDD failure (How to do?)

[Jim Popovitch]

Ryan Fish wrote:
> 
> OK, so...
> 
> 1) Physically replace drive
> 2) Create partitions (make sure type is "fd", probably don't need to specify
> "a" on mirror of /boot but might not hurt either)

I would only set "a" on the second drive to what ever "a" is set to on 
the first.  It should be the first partition, but I've seen it 
differently sometime in the past.

> 3) Use raidhotadd or mdadm to rebuild arrays (md0, 1 and 2)
> 
> A co-worker is donating a spare HDD he has so I can test this out at home on
> my CentOS box.  I figure it doesn't matter TOO much if I blow it up...

An alternative way to test is to d/l VMWare server (it's free, but still 
pre-release status) and install it on your desktop/laptop.  Then connect 
to it from the same system (or another one) and create a virtual 
machine.  Edit the virtual machine's settings to give it two drives, 
then install CentOS or whatever distro is at the remote site.  Set it up 
with full raid working, then shutdown the virtual machine and remove one 
of the drives from the config.  Then add a new (third) drive, and use it 
as instead of the removed one.  Assuming that you have the time to do 
this. ;-)

-Jim P.