Re: 4 partition raid 5 with 2 disks active and 2 spare, how to force?

[Luca Berra <bluca@comedia.it>]

On Sun, Mar 28, 2010 at 10:05:58PM +0530, Anshuman Aggarwal wrote:
>> Michael,
>> I am running mdadm 3.1.2 (latest stable I think) compiled from source (FYI on Ubuntu Karmic, 2.6.31-20-generic)
>> 
>> Here is what happened....the device /dev/sda1 has failed once, but I was wondering if it was a freak accident so I tried adding it back..and then it started resyncing ...somewhere in this process...the disk /dev/sda1 stalled and the server needed a reboot. After that boot, I got 2 spares (/dev/sda1, /dev/sdd5) and 2 active devices (/dev/sdb1, /dev/sdc1)
>> 
>> Maybe I need to do a build with a --assume-clean with the devices in the right order (which I'm positive I can remember) ...be nice if you could plz double check:
>> mdadm --build -n 4 -l 5 -e1.2 --assume-clean /dev/md127 /dev/sda1 /dev/sdb5 /dev/sdc5 /dev/sdd5
>> 
>> Again, thanks for your time...
>> 
>> John,
>> I did try what you said without any luck(--assemble --force but it refuses to accept the spare as a valid device and 2 active on a 4 member device isn't good enough)
>> 
>> 
>> 
>
>Some more info:
>
>I did try this command with the following result:
>
>mdadm --build -n 4 -l 5 -e1.2 --assume-clean /dev/md127 /dev/sda1 /dev/sdb5 /dev/sdc5 /dev/sdd5
>mdadm: Raid level 5 not permitted with --build.
>
>Should I try this?
>mdadm --create -n 4 -l 5 -e1.2 --assume-clean /dev/md127 /dev/sda1 /dev/sdb5 /dev/sdc5 /dev/sdd5
 From your description above /dev/sda was the failed one, so you should
not add it to the array. use the word "missing" in its place.

L.

-- 
Luca Berra -- bluca@comedia.it
         Communication Media & Services S.r.l.
  /"\
  \ /     ASCII RIBBON CAMPAIGN
   X        AGAINST HTML MAIL
  / \