3.1.14 Set maximum connection limits - MAX_COORDAGENTS

Information

The max_connections parameter indicates the maximum number of client connections allowed per database partition. It is recommended that this parameter be set equal to the max_coordagents parameter. The max_coordagents parameter equals the maximum number of agents needed to perform connections to the database or attachments to the instance.
NOTE: Ensure that dependent parameters, such as maxappls, are set less than the max_coordagents parameter. This would ensure that the lock limit is not reached, which would result in lock escalation issues.

By default, DB2 allows an unlimited number of users to access the DB2 instance. In addition to giving access to the DB2 instance to authorized users only, it is recommended to set a limit to the number of users allowed to access a DB2 instance. This helps prevent denial of service conditions should an authorized process malfunction and attempt a large number of simultaneous connections.

Solution

The default value for max_coordagents is AUTOMATIC. Allowable range is 1 to 64,000, or -1 for unlimited. The recommended value is 100. The following command will set max_coordagents to 100, as well as set max_connections to AUTOMATIC which is also recommended.
1. Attach to the DB2 instance
db2 => attach to $DB2INSTANCE
2. Run the following command from the DB2 command window:
db2 => update database manager configuration using max_coordagents 100 AUTOMATIC

3. If maxappls is NOT less than max_coordagents, then adjust the value of maxappls accordingly:
db2 => update database configuration using maxappls <a number less then max_coordagents>
Default Value:
The default value for max_connections is AUTOMATIC. The default value for max_coordagents is AUTOMATIC. The default value for maxappls is AUTOMATIC.

See Also

https://workbench.cisecurity.org/files/1654

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-10

Plugin: IBM_DB2DB

Control ID: a960d999fbdfc222ab18327db27a1d9e17f57da1e00ad1d23ece481d043e1e37