You use partitioned database environment variables to control
the default behavior of a partitioned database environment, including
authorization, failover, and network behavior.
- DB2CHGPWD_EEE
-
- Operating system: DB2® ESE
on AIX®, Linux, and Windows
- Default=NULL, Values: YES or NO
- This variable specifies whether you allow other users to change
passwords on AIX or Windows ESE systems. You must ensure that
the passwords for all database partitions or nodes are maintained
centrally using either a Windows domain
controller on Windows, or
LDAP on AIX. If not maintained
centrally, passwords may not be consistent across all database partitions
or nodes. This could result in a password being changed only at the
database partition to which the user connects to make the change.
- DB2_FCM_SETTINGS
-
- Operating system: Linux
- Default=YES, Values:
- FCM_MAXIMIZE_SET_SIZE:[YES|TRUE|NO|FALSE].
The default value for FCM_MAXIMIZE_SET_SIZE is YES.
- FCM_CFG_BASE_AS_FLOOR: [YES|TRUE|NO|FALSE].
The default value for FCM_CFG_BASE_AS_FLOOR is NO.
- You can set the DB2_FCM_SETTINGS registry
variable with the FCM_MAXIMIZE_SET_SIZE token to
preallocate a default 4 GB of space for the fast communication manager
(FCM) buffer. The token must have a value of either YES or TRUE to
enable this feature.
You can use the DB2_FCM_SETTINGS registry
variable with the FCM_CFG_BASE_AS_FLOOR option to
set the base value as the floor for the fcm_num_buffers and fcm_num_channels database
manager configuration parameters. When the FCM_CFG_BASE_AS_FLOOR option
is set to YES or TRUE, and these
parameters are set to AUTOMATIC and have an initial
or starting value, DB2 will
not tune them below this value.
- DB2_FORCE_OFFLINE_ADD_PARTITION
- Operating system: All
- Default=FALSE, Values: FALSE or TRUE
- This variable allows you to specify that add database partition
server operations are to be performed offline. The default setting
of FALSE indicates that DB2 database
partition servers can be added without taking the database offline.
However, if you want the operation to be performed offline or if some
limitation prevents you from adding database partition servers when
the database is online, set DB2_FORCE_OFFLINE_ADD_PARTITION to TRUE.
When this variable is set to TRUE, new DB2 database partition servers are added according
to the Version 9.5 and earlier versions' behavior; that is, new database
partition servers are not visible to the instance until it has been
shut down and restarted.
- DB2_NUM_FAILOVER_NODES
-
- Operating system: All
- Default=2, Values: 0 to the required number of database partitions
- Set DB2_NUM_FAILOVER_NODES to specify the
number of additional database partitions that might need to be started
on a machine in the event of failover.
In a DB2 database high availability solution, if a
database server fails, the database partitions on the failed machine
can be restarted on another machine. The fast communication manager
(FCM) uses DB2_NUM_FAILOVER_NODES to calculate
how much memory to reserve on each machine to facilitate this failover.
For
example, consider the following configuration:
- Machine A has two database partitions: 1 and 2.
- Machine B has two database partitions: 3 and 4.
- DB2_NUM_FAILOVER_NODES is set to 2 on both
A and B.
At START DBM, FCM will reserve enough memory on both A and B
to manage up to four database partitions so that if one machine fails,
the two database partitions on the failed machine can be restarted
on the other machine. If machine A fails, database partitions 1 and
2 can be restarted on machine B. If machine B fails, database partitions
3 and 4 can be restarted on machine A.
- DB2_PARTITIONEDLOAD_DEFAULT
-
- Operating system: All supported ESE platforms
- Default=YES, Values: YES or NO
- The DB2_PARTITIONEDLOAD_DEFAULT registry
variable lets users change the default behavior of the load utility
in an ESE environment when no ESE-specific load options are specified.
The default value is YES, which specifies that in
an ESE environment if you do not specify ESE-specific load options,
loading is attempted on all database partitions on which the target
table is defined. When the value is NO, loading is
attempted only on the database partition to which the load utility
is currently connected.
Note: This variable is deprecated and may be
removed in a later release. The LOAD command has various options that
can be used to achieve the same behavior. You can achieve the same
results as the NO setting for this variable by specifying
the following with the LOAD command: PARTITIONED
DB CONFIG MODE LOAD_ONLY OUTPUT_DBPARTNUMS x, where x is
the partition number of the partition into which you want to load
data.
- DB2PORTRANGE
-
- Operating system: Windows
- Values: nnnn:nnnn
- This value is set to the TCP/IP port range used by FCM so that
any additional database partitions created on another machine will
also have the same port range.