$CRS_HOME/bin/onsctl pingONS config information could also be seen in the ocrdump as well. This mismatch is noted in metalink notes 744849.1,754619.1 and 759895.1. It is important that hostname in the ons config and hostname given by the linux hostname command match. It is vital for Fast Connection Failover (FCF metalink note 566573.1) used in java applications with jdbc.
Number of onsconfiguration retrieved, numcfg = 2
onscfg[0]
{node = db01, port = 6251}
Adding remote host db01:6251
onscfg[1]
{node = db02, port = 6251}
Adding remote host db02:6251
ons is running ...
$ hostname
db02.edsa.local
If the hostname is a mismatch the FCF will not work.
To fix it simply remove the invalid hostname entry and add the full hostname
# racgons remove_config short_hostname
# racgons add_config full_hostname:6251