RAC Attack - Oracle Cluster Database at Home/11gR2 Bug Workaround


Several NFS appliances and big-iron cluster filesystems are very common in large cluster database deployments. We will use OCFS2 here to practice 11gR2 RAC with a filesystem.

Note: 11gR2 clusterware has a bug – it does allow cluster files on OCFS2 (even though this is a supported configuration). To work around this bug, we will present the OCFS2 directory to clusterware with a local "loopback" NFS mount.



  1. As the root user, Follow the steps below to setup the local NFS mount on node collabn1. [root@collabn1 ~]# mkdir /u61 [root@collabn1 ~]# vi /etc/fstab # create an NFS mount on u61 which points back to u51 localhost:/u51 /u61 nfs \ rw,bg,hard,nointr,rsize=32768,wsize=32768,tcp,vers=3,timeo=600,noac [root@collabn1 ~]# vi /etc/exports /u51 *(rw,no_root_squash,sync) [root@collabn1 ~]# chkconfig nfs on [root@collabn1 ~]# service nfs start [root@collabn1 ~]# mount /u61
  2. Repeat all of these steps on node collabn2. [root@collabn1 ~]# ssh collabn2 [root@collabn2 ~]# mkdir /u61 [root@collabn2 ~]# vi /etc/fstab # create an NFS mount on u61 which points back to u51 localhost:/u51 /u61 nfs \ rw,bg,hard,nointr,rsize=32768,wsize=32768,tcp,vers=3,timeo=600,noac [root@collabn2 ~]# vi /etc/exports /u51 *(rw,no_root_squash,sync) [root@collabn2 ~]# chkconfig nfs on [root@collabn2 ~]# service nfs start [root@collabn2 ~]# mount /u61