The grid control 12.0.2 on Oracle Linux 5.9 shows that status of target /EMGC_GCDomain/GCDomain/EMGC_ADMINSERVER as down where as it is up and running and I can log into admin console.
Please note that repository, OMS, weblogic all components are on same server.
It is also showing that following are unreachable where as these are up on same server
EM Website System
Management Services and Repository