Database Hung. Users were not able to connect
DB version:10gR2
OS: AIX 5.3
Yesterday one of our development databases got hung. Users were not able to connect. If you try to connect using sqlplus, it will just hang and then error out with some timeout message.
When i looked at the OS stats, the machine seemed to be relatively busy(topas command showed that CPU 70%, Disks 85% busy, Network stats are OK) . But it had always been like that.
All the mandatory processes were running. Nothing came up in alert log. I could log in as SYS locally (sqlplus / as sysdba) without any issues though.
Since it was urgent, i just did a restart and everything was working fine.
If you guys face a similair issue, what are all the places you guys will be looking to find the cause?