Grid DBA

Ever received this error message in your alert log? I have on a couple of occasions. Perhaps an application server started spawning more database connections than it normally does in turn creating more processes on the database. The Oracle description of this error is: Error: ORA 20 Text: maximum number of processes exceeded   Cause: An operation requested a resource that was unavailable. The maximum number of processes is specified by the initialization parameter PROCESSES. When this maximum is reached, no more requests are processed. Action: Try the operation again in a few minutes. If this message occurs often, shut down Oracle, increase the PROCESSES parameter in the initialization parameter file, and restart Oracle. But what if you cannot connect to your database to shut it down and increase the parameter? oradba01t[labdb01]-/home/oracle/>sqlplus  /as sysdba SQL*Plus: Release 11.1.0.7.0 - Production on Mon Jun 6 11:25:05 2011 Copyright (c) 1982, 2008, Ora...

Having worked on Oracle RAC since 9i, there hasn't been a time when I haven't faced something new or realized something was not what I thought it was. I think this is one of the reasons why I enjoy working on these systems - always a challenge. I stopped my RAC database to put it into noarchivelog mode using the srvctl command [oracle@oradba10t oracle]$ srvctl stop database -d labrac Next I proceeded to connect to the first instance to startup in mount mode [oracle@oradba10t oracle]$ sqlplus /nolog SQL*Plus: Release 10.2.0.4.0 - Production on Thu May 5 09:47:15 2011 Copyright (c) 1982, 2007, Oracle.  All Rights Reserved. SQL> conn / as sysdba Connected to an idle instance. SQL> startup mount ORA-29760: instance_number parameter not specified Wait, what's this? I've never encountered this error message before. Googled a bit and realized that most of the responses were a bit far fetched since the database had been in perfect working order before I stopped...