[CentOS] vpopmail over NFS not seeing new messages.

Tue Feb 28 12:29:04 UTC 2006
Will McDonald <wmcdonald at gmail.com>

Hi all.

We've just migrated our back-end NFS mailstore from FC1 systems to
CentOS4 and are experiencing problems/delays with vpopmail and user
Maildirs. IMAP is fine, it's just POP access that causes us problems.

Now, NFS mounts successfully, the clients can see /home/vpopmail and
serve content as we would expect. IMAP works perfectly and sees new
messages as soon as they're delivered into the Maildir, but POP
doesn't seem to see new messages until about 90 minutes after it

Messages can be seen in users' Maildir/new on the filesystem. The
timestamps on new messages on the NFS filesystems don't appear to be
formatted correctly, I'm guessing this could cause the POP weirdness?

On an NFS client...
[root at mailserv2 new]# ls -ltr
total 4
-rw-------  1 vpopmail vchkpw 854 Feb 28  2006 1141126119.27119.mailserv1,S=773

Whereas on the NFS mailstore...
[root at tempmailstore1a new]# ls -ltr
total 4
-rw-------  1 vpopmail vchkpw 854 Feb 28 12:44 1141126119.27119.mailserv1,S=773

'touch'ing the files, either from the client or server doesn't appear
to fix the timestamps.

The old FC mailstores were running...
kernel 2.4.22-1.2188.nptl
DRBD 0.6.12

The new CentOS mailstores and all their clients are running...
kernel 2.6.9-22.0.1.ELsmp
DRBD 0.7.14
Qmailrocks 2.2.0

/etc/exports on the mailstores contains...
/mnt/drbd/      mailserv1(rw,sync,no_root_squash)
/mnt/drbd/      mailserv2(rw,sync,no_root_squash)
/mnt/drbd/      mailserv3(rw,sync,no_root_squash)
/mnt/drbd/      mailserv4(rw,sync,no_root_squash)

And the NFS mounts on the client mailservers look like...

mailstore1:/mnt/drbd/home /home nfs defaults 0 0

If anyone's seen this or can shed any light it'd be much appreciated.