OID is Down For Ambiguous Reasons

Today one of the customer called complaining about accessing to the system and how its not working ? Since everything is configured as single sign on (SSO) first thing to check was OID or oracle internet Directory.

The logs indicate to the below error :-

[2015-05-01T07:00:18+03:00] [OID] [NOTIFICATION:16] [] [OIDMON] [host: MOAPRDOID1] [pid: 5244] [tid: 0] Guardian: [oidmon]: Unable to connect to database,
will retry again after 10 sec

[2015-05-01T07:00:28+03:00] [OID] [NOTIFICATION:16] [] [OIDMON] [host: MOAPRDOID1] [pid: 5244] [tid: 0] Guardian: Connecting to database, connect string is oiddb

[2015-05-01T07:00:28+03:00] [OID] [NOTIFICATION:16] [] [OIDMON] [host: MOAPRDOID1] [pid: 5244] [tid: 0] Guardian: [gsdsiConnect] ORA-12514, ORA-12514: TNS:listener does not currently know of service requested in connect descriptor.

from the above error the OID is unable to connect to database server i checked database and listener everything is up without any issue and all the other application working without any issues.

after investigation I checked the sqlnet.ora and add the following :-

SQLNET.AUTHENTICATION_SERVICES= (NONE)
NAMES.DIRECTORY_PATH= (TNSNAMES)

Restart the services and everything is working.

maybe this solution will not lead or help in so many cases i am working to know why this will effect on OID since it’s was working without any issues for 1 year

Thanks
Osama