Database Reference
In-Depth Information
Above all, you can also configure a mixed environment: both shared and non-shared Oracle Homes in a single
environment. When you have such mixed environment, on selected nodes you can implement shared Oracle Homes
to take advantage of storage and other benefits talked about a little earlier. The following configuration is possible in a
single environment:
•
A non-shared Grid home among all the nodes
•
A shared ORACLE RDBMS HOME among all the nodes
•
A shared ORACLE RDBMS HOME for a group of nodes and a non-shared ORACLE RDBMS
HOME for the rest of the nodes
Figure
7-1
depicts non-shared, shared, and mixed OH env settings.
Non-shared OH env
Mixed OH env
Node_1
Node_2
Node_3
Node_1
Node_2
Node_3
Node_4
/u00
/u00
/u00
/u00/GI
/u00/RDBMS
/u00/GI
/u00/GI
/u00/GI
/u00/RDBMS
Shared OH env
/opt/RDBMS
Node_1
Node_2
Node_3
/u00
Figure 7-1.
Shared/non-shared/mixed OH environment
Server Pools
A new feature introduced with 11gR2, server pools, is a dynamic grouping of Oracle RAC instances into abstracted
RAC pools, by virtue of which a RAC cluster can be efficiently and effectively partitioned, managed, and optimized.
Simply put, they are a logical grouping of server resources in a RAC cluster and enable the automatic on-demand
startup and shutdown of RAC instances on various nodes of a RAC cluster.
Server pools generally translate into a hard decoupling of resources within a RAC cluster. Databases must be
policy managed, as opposed to admin managed (the older way of RAC server partitioning: pre-11gR2) for them to be
organized as/within server pools.
Each cluster-managed database service has a one-to-one relationship with server pools; a DB service cannot be a
constituent of multiple server pools at the same time.
server pools and policy management of RAC database instances come in real handy when you have large RAC
clusters with a lot of nodes present. However, this technology can be used for policy-based management of smaller
clusters as well.
