Hi, On 13.04.2010 12:48, Dejan Muhamedagic wrote: > >> 2. It seems that /var/lib/nfs/rmtab is not used in NFSv4 so I just deleted >> the backup/restore >> procedures. May be it could be a configuration option or runtime check for >> version 4 that >> disables these procedures. >> > Are you sure it's not used? Isn't that implementation dependent? > > I could not be sure. My tests are on Debian/lenny with kernel 2.6.31. As I understand, nfs4 does not need rpc.mountd in nfs4, because mounts are just TCP session. On my setup even with mountd started the rmtab is not populated when there are only v4 clients
>> On itself exportfs RA worked as expected, though there was some unexpected >> interaction between >> NFSv4 server and the underlying FS. If some NFSv4 clients keep an open >> file of an exported >> directory, even if I completely stop the nfsd, there is some timeout >> before I could umount the >> underlying FS on the server (XFS here). Meantime I keep getting "device >> busy error". >> > Open files are likely to happen, perhaps there is some nfs > parameter to reduce the timeout. > >> What I have done: In the Filesystem RA I have increased the sleep interval >> in the "stop" op. Also I >> have configured 4 minutes timeout for the stop op. May be this sleep value >> could be configurable: >> I could imagine other scenarios where tweaking it could be useful. >> > Four minutes is quite long. Why would you want to increase the > sleep interval? To reduce the number of logged messages? > > Filesystem "stop" action tries to umount the filesystem. If it does not succeed it kills all processes that use the filesystem (nothing in my case because this are not processes but the kernel that keeps open filehandles). Then sleeps some interval (1s in the distribution) and tries again. After the 6th itetation (TERM TERM TERM KILL KILL KILL) the RA gives up and fails the op. I have increased the sleep interval in order to make the RA successfully stop the resource (umount the FS). The default of 6 seconds in total (6 interations with 1s sleep) would be quite short on every nfs4 setup. On my test setup the filesystem is released for 60-80 sec. I added the default Filesystem RA stop timeout of 60 sec. And I doubled the interval to be on the safe side. Other possible scenario where tunable "sleep" could be useful: imagine you have some unmanaged service using the filesystem that needs some time for proper shutdown (flushing files etc.). In the default setup it will be killed with SIGKILL (9) on the 3rd second. If the sleep is a RA parameter you could give it some more time for proper shutdown. Best regards Luben _______________________________________________________ Linux-HA-Dev: [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha-dev Home Page: http://linux-ha.org/
