Solaris Cluster 3.x: Troubleshooting ORA-29740 in a Oracle RAC environment
(Doc ID 1018609.1)
Last updated on AUGUST 11, 2020
Applies to:Solaris Cluster - Version 3.1 to 3.3 [Release 3.1 to 3.3]
Oracle Solaris on SPARC (64-bit)
Oracle Solaris on SPARC (32-bit)
Oracle Solaris on x86-64 (64-bit)
Oracle Solaris on x86 (32-bit)
An ORA-29740 error occurs when a member (node) was evicted from the group by another member of the cluster database for one of several possible reasons which may include a communications error within the cluster, failure to issue a heartbeat to the control file, and/or other reasons.
This mechanism is in place to prevent problems from occurring that would affect the entire database. For example, instead of allowing a cluster-wide hang to occur, Oracle will evict the problematic instance(s) from the cluster. When an ORA-29740 error occurs, a surviving instance will remove the problem instance(s) from the cluster. When the problem is detected, the instances 'race' to get a lock on the control file (Results Record lock) for updating. The instance that obtains the lock tallies the votes of the instances to decide membership.
A member may be evicted if:
a) A communications link is down
b) There is a split-brain (more than 1 subgroup) and the member is not in the largest subgroup
c) The member is perceived to be inactive (ie. hung)
Sample message in Alert log of the evicted instance may show:
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