Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Tue, Dec 13, 2005 at 09:54:40AM -0500, Todd Denniston wrote:
> >
> >Both nodes are always setup identical. I just tried two different setups:
> >
> >1.) the 'simple' setup with only one drbd as described in
> > http://linux-ha.org/DRBD_2fNFS, i.e. with a symlink from /var/lib/nfs
> > to the drbd-volume. Everything works perfectly, no errors on failover.
> >
> >2.) a setup without symlink but /var/lib/nfs as /dev/drbd0 and
> >/srv/nfs/mail
> > as /dev/drbd1. I get stale nfs errors during failover.
> >
>
> I find setup 2 to be interesting in its failure, because I would think it
> should work the same, but I have no idea why it fails.
Anyone else on the list?
> To me your haresources snipit looks reasonable for 0.7.x though I question
> two things:
>
> 1) Why do you run some kind of killnfsd before running `nfs-common start`
Because the 'DRBD Heartbeat and NFS on Debian HowTo' told me to...
You can find it on http://linux-ha.org/DRBD_2fNFS.
I left it out today and it makes no difference. My haresources for the
simple setup looks like this now:
b1 drbddisk::nfs \
Filesystem::/dev/drbd1::/srv/nfs::ext3::noatime \
nfs-common \
nfs-kernel-server \
sleep::3 \
IPaddr::194.95.249.20/24/eth0
Remember, I use a symlink /var/lib/nfs -> /srv/nfs/varlibnfs which helps
to avoid the Stale NFS error.
> and `nfs-kernel-server start`, if nfs for some reason was running when
> heartbeat got kicked off, what you really need to do is edit your rc config
> (on fedora I would use ntsysv ) to not start nfs services on boot.
I've done that. nfs is completely controlled by heartbeat!
> 2) why do you have a 3 second sleep between starting nfs and starting your
> Ethernet config?
Without the 'sleep 3' I get the Stale NFS error on the client. In this case
the nfs-server is shut down immediately after running 'IPaddr'. As it
seems the interface takes some time to really go away and as long as the
interface is up, the nfs-server should be as well..
Could anyone with more knowledge comment on this?
> I did just have a thought on your setup #2 (mounting /dev/drbd0 at
> /var/lib/nfs), try putting a 3 second sleep between the Filesystem call and
> the nfs startups. The thought being to make sure the /var/lib/nfs
> Filesystem is fully ready for use before trying to use it, i.e., see if it
> is a race condition.
I've set up my second setup:
b1 drbddisk::varlibnfs \
drbddisk::nfs \
Filesystem::/dev/drbd0::/var/lib/nfs::ext3::noatime \
Filesystem::/dev/drbd1::/srv/nfs::ext3::noatime \
nfs-common \
nfs-kernel-server \
sleep::3 \
IPaddr::194.95.249.20/24/eth0
and today I can switch back and forth between the two nodes without
error!
I can't say what has changed. Still investigating...
Regards
Raoul