|
| Oracle Clusterware !!!!!!! |
| Saturday, August 30, 2008 |
1) It was originally known as Oracle Parallel Server (OPS) and introduced in Oracle 6.0.35 (subsequently known as Oracle 6.2).
2) The OPS code matured through Oracle?, Oracle8, and Oracle 8L In Oracle 9.0.1, OPS was relaunched as the RAC option. It has continued to mature in Oracle 9.2 and Oracle 10.
3) Prior to Oracle 10.1, Clusterware was platform-dependent. On most platforms, Clusterware was provided by the hardware vendor. On Linux and Windows, however, the Clusterware was provided by Oracle.
4) In Oracle 9.0.1 and 9.2 on Linux this was known as the Oracle Cluster Manager (oracm).
5) In Oracle 10.1, Oracle supplies a complete, integrated Clusterware facility called Cluster Ready Services (CRS) on all platforms.
6) In Oracle 10.2, CRS has been renamed to Oracle Clusterware and is mandatory in Linux RAC environments, since third-party Clusterware is not supported by Oracle on the Linux platform.
7) Oracle Clusterware is installed as part of the RAC installation process.
8) In a RAC environment it is necessary to install and configure Oracle Clusterware before installing the Oracle database software.
- A separate ORACLE_HOME directory must be created for Oracle Clusterware.
- This directory continues to be referred to as CRSHOME in the Oracle 10.1 CRS terminology.
- Oracle Clusterware consists of the following components:
- Cluster Synchronization Services (CSS): manages cluster node membership
- Cluster Ready Services (CRS): performs management operations and high availability recovery
- Event Manager (EVM): manages event notifications and callouts
When Oracle Clusterware is installed, entries are added to the /etc/inittab file, and the in it process spawns the EVMD, OCSSD, and CRSD processes when the node is rebooted.
In Oracle 10.2 and above, Oracle
Clusterware can be started and stopped using the CRSCTL (Cluster Ready Services Control) command.
Oracle Clusterware uses two additional files that must be accessible to all nodes. These are the Oracle Cluster Registry (OCR) and the voting disk. |
posted by Jaswinder Singh @ 1:08 AM   |
|
|
|
|
|
