Hi, I remember that this has been tought in every cluster-training I attended - AIX-HACMP, Sun-Cluster, Veritas-Cluster. I also remember an elderly white paper from sun where nfs was explained in full detail.
The basic - from what I remember - is the NFS-protocol and the resulting client-behaviour. I think the problem is the IP/RPC-protocol: Once you have a NFS-connection the client retries its connection with rpc-retries. If the server comes up with IP first there is no rpc-service that could answer the rpc-request, so the reconnect fails on IP-level, thus possibly terminating the client-nfs-session. I did a search but could not find a complete state transition diagram for nfs. But anyway - if the server-ip comes up last, the rpc-retry will be served and the nfs-reconnect will be successful (if the nfs-client-handle: IP, device major number and inode-number of the file has not changed during failover). Kind regards, Nils > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Ryan Thomson > Sent: Tuesday, May 20, 2008 6:30 PM > To: General Linux-HA mailing list > Subject: Re: [Linux-HA] NFS Configuration > > Hi, > > What is the technical explanation for starting the IP > resource LAST? I've experienced both successful and > unsuccessful NFS failovers and I haven't yet had a chance to > look much further than the well documented tweaks and > settings (if this is well documented, I must have missed it). > My IP resource does start FIRST and perhaps this may start to > explain the bad failovers I've seen. > > Any additional information regarding this would be very helpful. > > Thanks, > > -- > Ryan Thomson > > Hildebrand, Nils, 232 wrote: > > Hi, > > > > just a short remark: > > With NFS the IP-Resource should be the LAST resource to > start - else > > your NFS-Clients will run into trouble in case of failover. > > > > Kind regards, > > > > Nils > > > > > >> -----Original Message----- > >> From: [EMAIL PROTECTED] > >> [mailto:[EMAIL PROTECTED] On Behalf Of Beren > >> Gamble > >> Sent: Wednesday, May 07, 2008 4:53 PM > >> To: [EMAIL PROTECTED]; [email protected] > >> Subject: Re: [Linux-HA] NFS Configuration > >> > >> > >>> I guess then that it depends on the service. AFAIK, most > >> services read > >>> configuration files only at startup. On the other hand, most also > >>> cause things like flushing buffers at exit, so that may be > >> the reason > >>> for failed stops. Of course, the heartbeat configuration > >> itself has to > >>> be on a local node. Which services do you run? > >> Thanks for the reply... > >> > >> This is our haresources file > >> > >> web1n1 10.1.66.44 > >> Filesystem::hcfiler2:/vol/vol_Web::/Web::nfs::soft mysql-web > >> apache::/etc/apache2-web/apache2-web.conf mon tomcat5-web > >> web1n2 10.1.66.45 > >> Filesystem::hcfiler2:/vol/vol_Intranet::/Intranet::nfs::soft > >> mysql-intranet > >> apache::/etc/apache2-intranet/apache2-intranet.conf mon > >> tomcat5-intranet > >> > >> > >> Cheers! > >> > >> Beren > >> > >> [...] > > _______________________________________________ > > Linux-HA mailing list > > [email protected] > > http://lists.linux-ha.org/mailman/listinfo/linux-ha > > See also: http://linux-ha.org/ReportingProblems > _______________________________________________ > Linux-HA mailing list > [email protected] > http://lists.linux-ha.org/mailman/listinfo/linux-ha > See also: http://linux-ha.org/ReportingProblems > > _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
