Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
[I haven't seen Paul's message come through drbd-user yet but he did send it there in addition to direct to me.] On Thu, Mar 03, 2005 at 03:53:45PM -0500, Paul Nowoczynski wrote: > Hi, > > > > > I need some clarification on this. I have tried it both ways and have > > had a little better luck with having /var/lib/nfs be separate on the two > > servers than having it be a symlink to the shared filesystem. I have not > > seen EPERM errors after failover, but I do sometimes have NFS filesystems > > show up in 'df' on some clients as having some huge number of free blocks > > (which I assumed was a misinterpretation of -1) until I do "exportfs -r" > > on the new active server. Is that an EPERM error? It usually is not on > > all clients, just some of the ones in the netgroup that the filesystem is > > exported-to (and I've even seen it when explicitly listing all the hosts > > in /etc/exports). I'm quite sure I saw these problems with /var/lib/nfs > > as a symlink to the shared fileserver or not. If I make /var/lib/nfs > > a symlink to the shared filesystem, then it disappears on the standby > > server and 'df' hangs there when it gets up to the shared filesystem > > which I have mounted from the activer server by NFS. > > After some trip-ups, I've got a similar config working very well. > I've been sharing varlibnfs the entire time and have not seen any > problems - even after 20 or 30 failovers (hard and soft). One thing > I have learned is that running an nfs server on your standby machine > is a bad idea. I chkconfig nfs off on both of the machines and let > heartbeat start nfsd after it has mounted drbd. If the machine is > on standby, nfsd is not started at all. One time, after a machine was > rebuilt, nfsd was on be default and failovers ceased to work at all. I'm not running nfsd on the standby server either. I was only talking about acting as an NFS client. > I have not been mounting the ha share on the failover cluster nodes, > but I don't think that would be a bad thing - unless the nfs client > translates the vip to the loopback. Are you explicitly mounting the > vip via the nfs client or the real ip? I'd recommend that you don't allow > any non-vital processes on your failover cluster. I'm mounting the filesystem via the virtual IP address so it can continue to work before & after a failover. > paul - Dave > > > > Is it in general a Very Bad Thing to NFS-mount the shared filesystem on > > the HA-NFS servers? I have never seen anybody explicitly state that, > > although I'm beginning to come to that conclusion. I've had problems with > > fuser hanging on failover, and even after avoiding that I still sometimes > > see hangs on shutdown that I'm quite sure are related to operations > > attempting to access the non-responding NFS mountpoint. In my case the > > shared filesystem holds almost everybody's home directories so it's rather > > a pain to not be able to access them on the standby shared file server. > > I need to allow people to log in to the active server so I'd have to > > have their home directories be set up there to be symlinks directly to > > the mounted filesystem (because that's how we do CVS accesses to avoid > > problems with CVS over NFS), but that means that when a failover happens > > every process that is directly accessing the filesystem will get killed > > which isn't very friendly. > > > > - Dave Dykstra > > _______________________________________________ > > drbd-user mailing list > > drbd-user at lists.linbit.com > > http://lists.linbit.com/mailman/listinfo/drbd-user > >