Re: mdadm RAID5 Grow

[mickg <mickg@mickg.net>]

Neil Brown wrote:
> On Thursday October 5, mickg@mickg.net wrote:
>> Neil Brown wrote:
>>> On Wednesday October 4, mickg@mickg.net wrote:
>>>> I have been trying to run: 
>>>> mdadm --grow /dev/md0 --raid-devices=6 --backup-file /backup_raid_grow
>>>> I get:
>>>> mdadm: Need to backup 1280K of critical section..
>>>> mdadm: /dev/md0: Cannot get array details from sysfs
>>> It shouldn't do that.... 
>>> Can you 
>>>   strace -o /tmp/trace -s 300 mdadm --grow .....
> ...
>> open("/sys/block/md0/md/component_size", O_RDONLY) = -1 ENOENT (No such file or directory)
> 
> So it couldn't open .../component_size.  That was added prior to the
> release of 2.6.16, and you are running 2.6.17.13 so the kernel
> certainly supports it.  
> Most likely explanation is that /sys isn't mounted.
> Do you have a "/sys"?
> Is it mounted?
> Can you "ls -l /sys/block/md0/md" ??
> 
> Maybe you need to
>   mkdir /sys
>   mount -t sysfs sysfs /sys
> 
> and try again.
> 
Worked like a charm!

Thank you!

There is a
   sysfs   /sys    sysfs   noauto 0 0
line in /etc/fstab
I am assuming noauto is the culprit?

Should it be made to automount ?

mickg
> NeilBrown
> -
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