3ware 8506-4LP degraded RAID array rebuild (R10)

Another recent technology victory.

I didn't want to try a hot-swap.  Too important.

# tw_cli

> info c0

Shows that disk in port 2 (/c0/p2) is DEGRADED.  I wrote down the serial number of the degraded disk, in case the hardware port to driver port mapping was criss-crossed.

Nope.  Port 2 (3rd one down: 0, 1, then 2) actually housed the "bad" disk.  Put in the new disk.  Used the power-screwdriver at the colo (Bravo, HE) to mount the new one in the housing, and put it back in the array.

:)

Rebooted.  Alt-3, and selected the new disk (not a part of any array), and the degraded array.  This put an asterisk next to both, then tabbed down to [Rebuild Array].  It marked the array for a rebuild--this part was confusing--and said it would start on [F8].  I assumed (luckily correctly) that it was wanting me to put F8 to start the rebuild.  When I did, it continued the boot.

This is the part that seems like it should require more explicit direction or description.  I mean, clearly, if you reboot here, that would seem bad, unless the controller wrote something to the firmware.  I guess that makes sense.  Still, it would be nice if it told you that no matter what you did, it would be safe.  Still...

:/

Ok...Linux boots.  fsck has its fun.  And, when I get the shell back, I run tw_cli again.  It says the array has status "REBUILDING".

:)

I remembered something about being able to reset priorities during a rebuild...

# tw_cli

> set rebuild c0 1

The range of the last argument is from 1 to 5, inclusive.  5 is the lowest, prioritizing I/O over the rebuild.  1 is the highest, prioritizing the rebuild over I/O.  3ware FTW.

:))