Database Reference
In-Depth Information
Types of Server Pools
Server pools are classified into two types, both of which are explained in detail as follows:
•
System-defined server pools
•
User-defined server pools
System-Defined Server Pools
As the name implies, these server pools are created by default automatically with a new installation. Server pools of
this type house any/all non-policy-managed databases. System-defined server pools are further broken up into two
subcategories:
•
GENERIC server pool
In addition to RAC servers assigned to a system-defined server pool, all non-policy-managed (admin-managed)
databases are housed within the GENERIC server pool. The attributes of a GENERIC server pool are not modifiable.
•
FREE server pool
All unassigned RAC servers automatically get attached to the FREE server pool by default. Common attributes of
a server pool (MIN_SIZE, MAX_SIZE, SERVER_NAMES) are not modifiable within the FREE server pool. However, the
IMPORTANCE and ACL properties of the FREE server pool can be changed.
User-Defined Server Pools
The attributes of user-defined server pools are listed as follows. This methodology is termed “server categorization”
by Oracle.
•
NAME:
Define the name of the server pool with this attribute
•
IMPORTANCE:
Comparative importance of server pool. Values allowed in order of
importance: 0-1,000
•
MIN_SIZE:
Minimum no. of nodes within a server pool. Default value is 0
•
MAX_SIZE:
Maximum no. of nodes within a server pool. A value of -1 defines a cluster-wide
server pool
•
ACL:
Access Control List containing security/users/privileges information about the server
pool
•
SERVER_CATEGORY:
Defines server category; this is an attribute mutually exclusive
to the SERVER_NAMES attribute; only one can be set at a time (not both)
•
SERVER_NAMES:
A hard coupling of RAC servers to the server pool. This is an attribute
mutually exclusive to the SERVER_CATEGORY attribute; only one can be set at a time
(not both)
•
ACTIVE_SERVERS:
This is an auto-managed attribute and changes in real time
•
SERVERPOOL:
Name of the server pool
•
EXCLUSIVE_POOLS:
Defines whether the RAC servers are shareable among server pools
or not
•
PARENT_POOLS:
Specifies if a server pool is a child of another pool (nested pools)
