Agent-based Management method
Starting with the concept of multiuser in Oracle 11.2, Oracle began using a set of multi-threaded daemon to support the use and management of resources for multiple users at the same time, daemon called agents. These agents are memory-resident processes.
Classification of agents
- Oracle Grid 11.2 has multiple agents, of which two are the most important of the Oracle Agnet and Oracle root agent.
- Oracle Agnet is run as an Oracle user (this Oracle user is a generic, may be grid or Oracle depending on the occasion)
- The Oracle root agent is the name of the process that runs the operating system of this two agent as the root user: Oraagent and Orarootagent
- The Ohas stack will start a set of Oracle Agnet and Oracle root agents. Oracle Agnet initiated by Ohas is run as a grid installation user.
- The CRS stack also initiates a set of Oracle Agnet and Oracle root agents. If the user who installs the grid is not Oracle, it is a grid. The two Oracle agnet will be started.
Diagram of Agent and resource
corresponding log structure (by hierarchy of tree graph)
First floor
- OHASD logs are located at: $Grid _home/log/
The second layer: (OHASD agent)
- Cssdagent logs are located at: $Grid _home/log/
- Cssdmonitor logs are located at: $Grid _home/log/
- Orarootagent logs are located at: $Grid _home/log/
- Oraagent logs are located at: $Grid _home/log/
Third tier (resources)
- CSSD logs are located at: $Grid _home/log/
- CRSD logs are located at: $Grid _home/log/
- CTSSD logs are located at: $Grid _home/log/
- DiskMon logs are located at: $Grid _home/log/
OHASD the corresponding log of the resources managed by Oraagent:
- ORA.EVMD logs are located at: $Grid _home/log/
- ORA.MDNSD logs are located at: $Grid _home/log/
- ORA.GPNPD logs are located at: $Grid _home/log/
- ORA.GIPCD logs are located at: $Grid _home/log/
Fourth floor (agent of CRSD)
- Orarootagent logs are located at: $Grid _home/log/
- Oraagent (GRID) logs are located at: $Grid _home/log/
- Oraagent (Oracle) logs are located at: $Grid _home/log/
11g RAC R2 Architecture---Grid
