[Ocfs2-users] MySQL fails with tablespace on OCFS2

[Peter P GMX]

I have set up an cluster with ocfs2 on top of drbd in primary/primary mode.
As long as the datadir is in /var/lib/mysql, everything works fine.
But as soon as I put the datadir on the ocfs2 filesystem
  /mnt/data/mysql
mysql fails with:
  [Ubuntu] root at fs2:/etc# mysqld --safe-mode
  090930 18:08:14 [Warning] Can't create test file
/mnt/data/mysql/fs2.lower-test
  090930 18:08:14 [Warning] Can't create test file
/mnt/data/mysql/fs2.lower-test
  090930 18:08:14 InnoDB: Operating system error number 13 in a file
operation.
  InnoDB: The error means mysqld does not have the access rights to
  InnoDB: the directory.
  InnoDB: File name ./ibdata1
  InnoDB: File operation call: 'open'.
  InnoDB: Cannot continue operation.

When I temporarily login as user mysql and create the same file it can
create the file:
  $ whoami
  mysql
  $ echo a >/mnt/data/mysql/fs2.lower-test
  $ ls -al
  -rw-r--r-- 1 mysql mysql 2 2009-09-30 19:15 fs2.lower-test

I've also tried with an ext3 filesystem on the drbd device in
primary/secondary configuration, this worked fine.
So this only happens when the datadir is on a ocfs2 file system.

Some more facts:
- still the same error if filesystem is unmounted on the other machine
of the cluster
- O2CB_HEARTBEAT_THRESHOLD=31
- Ubuntu 8.043
- MySQL server is mysql-server 5.0.51a
- ocfs2-tools 1.3.9
- drbd8-utils 2:8.0.11-0

Has anybody experienced a similar problem? May it have to do with
locking or extended attributes?
I've also asked on the Mysql users side as I do not know whether this is
an OCFS or a MySQL problem.

Best regards
Peter