[Linux-cluster] Ondisk and fsck bitmaps differ at block XXXXXX

[Bob Peterson]

----- "de Jong, Mark-Jan" <deJongm at teoco.com> wrote:
| Hello,
| 
| After running our two node cluster concurrently for a number of days,
| I wanted to take a look at the health of the underlying GFS2 file
| system.
| 
| 
| 
| And although we didn’t run into any problems during or testing, I was
| surprised to still see hundreds of thousands, if not millions, of the
| following message when running and gfs2_fsck on the file system:
| 
| 
| 
| Ondisk and fsck bitmaps differ at block 86432030 (0x526d91e)
| 
| Ondisk status is 1 (Data) but FSCK thinks it should be 0 (Free)
| 
| Metadata type is 0 (free)
| 
| Succeeded.
| 
| 
| 
| I assume this is not good, although processes reading and writing
| to/from the filesystem seem to be running smoothly. I ran the fsck
| days after the last write operation on the cluster.
| 
| 
| 
| I’m currently running the following on Centos 5.4:
| 
| 
| 
| kernel-2.6.18-164.15.1.el5
| 
| cman-2.0.115-1.el5_4.9
| 
| lvm2-cluster-2.02.46-8.el5_4.1
| 
| 
| 
| The GFS2 file system is running on top of a clustered LVM partition.
| 
| 
| 
| Any input would be greatly appreciated.
| 
| 
| 
| Thanks,
| 
| Mark de Jong

Hi Mark,

These messages might be due to (1) bugs in fsck.gfs2, (2) the gfs2 kernel
module, or (3) corruption leftover from older versions of gfs2.  I have
a few recommendations:

First, try running my latest and greatest "experimental" fsck.gfs2.
It can be found on my people page at this location:

http://people.redhat.com/rpeterso/Experimental/RHEL5.x/gfs2/fsck.gfs2

If you want to wait a day or two, I'll be posting another version there
then because I've got an even better version I'm testing now.

As for gfs2, we've fixed several bugs in 5.5 so you might want to
look into moving up to 5.5 as well.

Regards,

Bob Peterson
Red Hat File Systems