Problem with RHEL 5.4 and Oracle RAC


I Ran into an issue while working with Oracle Corporation on 11gR2 RAC and RHEL 5.4 using OS layer files and OCFS2 for storage.  Now Oracle is currently saying that no known problem exists, but I thought I would drop a note here, just in case anyone comes across the same situation.   It appears that when you upgrade your RHEL kernel from version 2.6.18-194.26.1.el5 to 2.6.18-238.1.1.el5 and of course upgrade your OCFS2 drivers to the same version.   Access to the shared files of RAC becomes an issue for Oracle upon installation and execution of  

We struggled with this for two weeks, and from the start said the only thing we did was upgrade the kernel.  However, Oracle repeatedly said all Kernels above 2.16.18 have no issues.    Finally, we downgraded the system back to the original kernel 2.6.18-194.26.1.el5 and re-applied the OCFS2 RPMs for that kernel and everything began to work. 

So if you are have problems with Oracle 11g RAC install on RHEL 5.4 with kernel 2.6.18-238.1.1.el5 and can find no reasonable solution.  You may want to downgrade your kernel and try again.   It actually only took 45 minutes to downgrade, update the Oracle RPMs and provided a solution to a two week old problem. 


Larry J. Catt, OCP 9i, 10g

SSH, PING, and RSH – Permissions causing failure on Oracle RAC Installation

Oracle RAC requires permissions to networking components which are typically restricted on most systems. Most notable are permissions to utilities SSH, PING, and RSH. If you are attempting to install Oracle RAC software and you are receiving failures in communications; check the permissions of these utilities for a possible cause.

1. Logon to your Linux server as root.

2. Change the permissions on the following files to u+s.

chmod u+s /bin/ping
chmod u+s /usr/bin/ssh
chmod u+s /usr/bin/rsh

This completes allowing Oracle permissions to SSH, PING, and RSH for RAC configurations.
Larry J. Catt, OCP 9i, 10g