Re: [Evms-devel] Possible to create a degraded RAID5 array with EVMS?

[Mike T. <mh...@us...>]

Mike Tran wrote:

>On Sat, 2005-11-26 at 14:42, James Lee wrote:
>  
>
>>Hi there,
>>
>>I'm having some more trouble with getting EVMS and mdadm to play nicely 
>>together (even after upgrading EVMS)...
>>
>>The steps I'm taking are:
>>
>>1. Starting with an empty drive (wiped it by zero-filling the start and end 
>>of drive to make sure there's no residual partition table information).  
>>Create two logical partitions (/dev/sdb5 and /dev/sdb6).
>>
>>2. Use mdadm to create a degraded "3-drive" RAID5 array called /dev/md0: 
>>"mdadm --create /dev/md0 --level=5 --raid-devices=3 /dev/sdb5 /dev/sdb6 
>>missing".
>>
>>3. Start EVMS.  It correctly detects the degraded RAID5 array on /dev/md0.
>>
>>4. In EVMS, create 4 partitions on /dev/sdb, each one just over half the 
>>size of the partitions in the RAID5 array.  Create two 2-drive RAID0 
>>stripes, from these partitions.
>>
>>5. Add one of these RAID0 arrays to the RAID5 array.  Wait for it to resync. 
>>  RAID5 array is now active and non-degraded.
>>
>>6. Create an EXT3 filesystem and bung some files on it.
>>
>>7. Everything working fine so far.  Now expand the RAID5 array with the 
>>other RAID0 array.  This seems to work fine.  No data lost on the partition 
>>and no errors.
>>
>>8. Reboot.  When next starting EVMS, I get the following errors:
>>
>>    
>>
>
>In theory, this should work!!! I will try your scenario to find out what
>went wrong.
>
>  
>
I could not reproduce this problem using evms 2.5.3.  Did you wait for 
the raid5 expand to complete before rebooting the machine?

--
Mike T.