Oracle Database Discussions

Hello all,

I've run into a problem where I've lost my tape drive...and have no sysadmins to help.

I don't want my RAC instances to run our of space and halt, so I'm planning to take them out of archive log mode, and just do exports daily till I can move them or get tape going again.

This is easy enough with a non-clustered instance, but I'm reading around and finding conflicting information for doing it on a RAC system.

In the Oracle® Real Application Clusters Administration and Deployment Guide
11g Release 2 (11.2)...it states in simple terms:

(http://download.oracle.com/docs/cd/E11882_01/rac.112/e16795/rman.htm#i474611)

"In order for redo log files to be archived, the Oracle RAC database must be in ARCHIVELOG mode. You can run the ALTER DATABASE SQL statement to change the archiving mode in Oracle RAC, because the database is mounted by the local instance but not open in any instances. You do not need to modify parameter settings to run this statement."

and thats about it.

I've been researching and found a couple of other non-oracle official guides to this, where they describe a much more involved process, that seems to follow this path:

1. sqlplus into one instance and change the cluster_database=false scope=spfile sid='specific_node_name';

2. Shut down all instances, srvctl stop database -d <instance_name>

3. Startup the instance you changed cluster_database on with sqlplus and startup mount;

4 On this instance you do ALTER DATABASE NOARCHIVELOG;

5. On same instance change the cluster parameter back: alter system set cluster_database=true scope=spfile sid='specific_node_name';

6. Shut down this single instance

7. Start all instances with srvctl start database -d <instance>


I've found references to this at:

http://oracle-dba-yi.blogspot.com/2010/12/enabledisable-archive-log-mode-in-11gr2.html

and

http://www.dba-oracle.com/bk_disable_archive_log_mode.htm

Among other sites. I'm curious why the Oracle documentation on this doesn't mention all these steps?

I'm guessing the longer version is the path I should take, but I wanted to ask here first if this is correct?

I'm on Oracle 11Gr2....hasn't been patched with latest patchset, running on RHEL5, and is a 5 node cluster.


Thank you in advance,

cayenne

Edited by: cayenne on Oct 21, 2011 11:51 AM