Monitoring AIX 6.1 fails with the following errors found in the agent logs:
ECHO ERROR [Quartz-1] com.quest.remoteos.collectors.aix.AIXCollector - Could not process metric query command: . Error: Process /usr/bin/env LC_ALL=C /db2/foglight/fglam/agents/HostAgents/5.6.5-565-20121121-0406-b116/bin/aix/quest_perfstat exited with code 126
The Foglight Agent Manager (FglAM) was installed using user 'foglight' on the same monitored host while the DB2 agent was created to use a dedicated 'db2user'. When the Host Agent runs, it picks the credential of the 'db2user' and tried to execute the native collector quest_perfstat file then fails.
Since both 'foglight' and 'db2user' belongs to the same Unix group, the following steps helped fix the issue.