Hello List, I have a problem with a CentOS 5 server running Oracle DBMS with the transaction logs going to an NFS share on our CentOS 6/Bacula backup server. The Oracle server has this in its /etc/fstab file: backup:/home/backup/Oracle /backup_nfs nfs hard,intr,noexec,rsize=32768,wsize=32768 The backup server, in its /etc/exports: /home/backup/Oracle -rw,async,all_squash,anonuid=133 cen5-db-01 This works quite well, except that when all the servers are rebooted together (such as after a power outage) the Oracle server fails to mount the NFS share, but goes ahead to start Oracle anyway. Oracle then either complains that it cannot find its logs or, worse, starts to write them to the local disk. The last time this happened, I found a message on the console: mount: can't get address for backup So it seems that the failure was caused by the nameserver not being available yet. Unfortunately that message isn't saved to any logfile, so I cannot say if it was the same the previous times. How can I make sure that the system startup does not proceed until the NFS share is available and mounted successfully? From R'ingTFM I got the impression that this should be the default behaviour, but apparently it isn't. I don't know if hardcoding the backup server's IP address into the Oracle server's /etc/hosts file would help, but I would really like to avoid that, anyway. Thanks in advance for any hints, Tilman
On 19.4.2012 20:12, Tilman Schmidt wrote:> Hello List, > > > backup:/home/backup/Oracle /backup_nfs nfs > > The last time this happened, I found a message on the console: > > mount: can't get address for backup > > So it seems that the failure was caused by the nameserver not being > available yet. Unfortunately that message isn't saved to any logfile, > so I cannot say if it was the same the previous times.You could set in fstab ipaddress instead of the server name, so there is no need for name lookup or you can put the ip and name in /etc/hosts> How can I make sure that the system startup does not proceed until > the NFS share is available and mounted successfully? From R'ingTFM > I got the impression that this should be the default behaviour, but > apparently it isn't. I don't know if hardcoding the backup server's > IP address into the Oracle server's /etc/hosts file would help, but > I would really like to avoid that, anyway.Where the nameserver is? On the backup server or on the oracle (or on completely separate machine?) - If on oracle server, you could make that one to start before oracle in init. - If on separate machine you could write your own init script which tests that the name resolution works and runs the oracle startup after that. I would put the ip in hosts if the backup server has fixed ip-address. If not then making special init-script could be the trick. -vpk
On Apr 19, 2012, at 9:12 PM, Tilman Schmidt wrote:> Hello List, > > I have a problem with a CentOS 5 server running Oracle DBMS with > the transaction logs going to an NFS share on our CentOS 6/Bacula > backup server. The Oracle server has this in its /etc/fstab file: > > backup:/home/backup/Oracle /backup_nfs nfs > hard,intr,noexec,rsize=32768,wsize=32768 >Just add _netdev to the mount options. From man: _netdev The filesystem resides on a device that requires network access (used to prevent the system from attempting to mount these filesystems until the network has been enabled on the system). HTH, Vahan