In oracle RAC (10.2.0.4) environment; some time ons process will fail duo to localhost IP not fount in the /etc/hosts. It turned out to be local IP address not in the hosts file.
Error:
Check the log file for ons process.
# cat /home/oracle/product/crs/log/dbnode-001/racg/ora.dbnode-001.ons.log
2010-04-09 10:08:08.608: [ RACG][2540801280] [32516][2540801280][ora.dbnode-001.ons]: onsctl: shutting down ons daemon …
Failed to get IP for localhost (1)
onsctl: shutdown of ons failed!
Solution:
To solve this issue just insert the following line in your /etc/hosts file and started the crs
127.0.0.1 localhost.localdomain localhost
# cat /home/oracle/product/crs/log/dbnode-001/racg/ora.dbnode-001.ons.log
2010-04-09 10:26:36.647: [ RACG][2540809472] [6819][2540809472][ora.dbnode-001.ons]: Adding remote host dbnode-001.abcd.com:6200
onscfg[1]
{node = dbnode-001.abcd.com, port = 6200}
Adding remote host dbnode-001.abcd.com:6200
onsctl: ons started
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