Choosing RAW for Stability and Reliability Oracle Database Tips by Donald Burleson

With an understanding of the administrative limitations of raw partitions, it may come as a surprise that for the CRS configuration and voting files, this book will use raw partitions instead of OCFS. 

There are two very good reasons for doing so. The first is stability. Even after a successful install of CRS, with the configuration files on OCFS numerous instabilities have been seen. Rebooting tends to produce the error ?INIT: Id hx respawning too fast? which indicates that one or more of the CRS services has failed. 

The second reason is reliability of the install. Too frequently, when installing the CRS configuration files on OCFS, the error ?PRIF-12: failed to initialize cluster support services? appears at the very end of the install.

Because of ?interoperability problems with CRS and OCFS?, the MOSC note 264699.1 recommends using raw partitions. The OCFS release notes list a bug #3467544 that states, ?CSS fails to flush writes to voting file on OCFS.?

Using a 9i srvconfig file stored on OCFS for the OCR file will consistently produces an error on a 10g upgrade install (Oracle bug #3940214). These problems may have been addressed with the release of OCFS version 1.0.11, but my experience would indicate otherwise.

Moving the srvctl Repository to Raw

In an upgrade install from 9i to 10g, the repository for srvctl is reused so that the configuration stored in it is not lost. At this moment, that file is stored on OCFS.

The following list provides walk-through steps for moving the current file to a raw partition and preparing a second raw partition for the 10g voting file:   

1.      As oracle, stop gsdon both nodes.

2.      As root, bind the raw devices to the partitions as shown. Change ownership and permissions as shown. Repeat this step on each node. Raw3 will be used for the srvctl repository. Raw4 will be used for the 10g CRS voting file. The permissions on these files are critical to the success of the install!

3.      As root, open the file /etc/sysconfig/rawdevices with a text editor and add the new raw partitions so they will be bound on reboot. Repeat this step on each node.

4.      As root, open the file /var/opt/oracle/srvConfig.loc with a text editor and change the path to the raw partition as shown. Complete this step on each node.

5.      As oracle, start gsdon both nodes. This will ensure the file on the raw partition can be accessed properly.

As oracle, use the dd command as shown to overwrite any stray data on the raw partition that will be used for the 10g voting file. This will help ensure a trouble free install. This step can be done from either one of the nodes.

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