physical size of the device inconsistent with superblock, after RAID problems

[NeilBrown]

On Thu, 17 Feb 2011 15:53:11 -0800 (PST) Gavin Flower <gavinflower at yahoo.com>
wrote:

> Hi Neil,
> 
> My attempted post to ext3-users at redhat.com, had not been published there (even though I had emailed it 4 days ago!), as at a minute ago.
> 
> I finally bit the bullet and went ahead.
> 
> I accepted the fixes put forward by fsck associated with bitmap differences, and rebooted.
> 
> Still problems.
> 
> Still had the discrepancy in the file size.  So I ran the command:
> 
> resize2fs -p /dev/md1 76799616
> 
> I used the smaller of the 2 block counts, as:
> (a) I needed to reduce the file system size, because I had already reduced the RAID size (I _SHOULD_ have done this first, before resizing the RAID), and
> (b) it is reported as the 'physical' size of the device, so it is likely to be the correct value IMHO
> 
> The system the came up successfully after a reboot, and I was able to log in as normal.
> 
> There appeared to be no apparent loss of data, not that I did an exhaustive systematic check. However, several users have logged on successfully, and it is playing its part as gateway to the Internet, and squid appears to be providing its normal functionality.
> 
> Neil, your help and encouragement was/is greatly appreciated!
> 

Excellent!  I'm glad you found a way through.
As you didn't really trim very much from your device it is certainly possible
that no critical data was there.  Quite possibly resize2fs would have told
you if there was (I certainly hope it would have done).

NeilBrown