SUSPEND QMGR (suspend a cluster queue manager)

Using MQSC commands

For information on how you use MQSC commands, see Performing local administration tasks using MQSC commands.

Using SUSPEND QMGR on z/OS

SUSPEND QMGR can be used on z/OS. Depending on the parameters used on the command, it may be issued from various sources. For an explanation of the symbols in this table, see Sources from which you can issue MQSC commands on z/OS.

Usage notes

• If you define CLUSTER or CLUSNL, be aware of the following behavior:
  • The command fails if the channel initiator has not been started.
  • Any errors are reported to the system console where the channel initiator is running; they are not reported to the system that issued the command.
• The SUSPEND QMGR and RESUME QMGR commands are supported through the console only. However, all the other SUSPEND and RESUME commands are supported through the console and command server.

Parameter descriptions for SUSPEND QMGR

On z/OS, controls logging and update activity and how the command runs when the queue manager is a member of a queue sharing group.

You can use the SUSPEND QMGR FACILITY(Db2) command to terminate the queue manager connection to Db2®. This command might be useful if you want to apply service to Db2. Be aware, if you use this option then there is no access to Db2 resources, for example, large messages which might be offloaded to Db2 from a coupling facility.

You can use the SUSPEND QMGR FACILITY(IMSBRIDGE) command to stop sending messages from the IBM MQ IMS bridge to IMS OTMA. See Controlling the IMS bridge for more information about controlling message delivery to shared and non-shared queues.

CLUSTER (clustername)

The name of the cluster for which availability is to be suspended.

CLUSNL (nlname)

The name of the namelist that specifies a list of clusters for which availability is to be suspended.

FACILITY

Specifies the facility to which connection is to be terminated. The parameter must have one of the following values:

Db2

Causes the existing connection to Db2 to be terminated. The connection is re-established when the RESUME QMGR command is issued. When the Db2 connection is SUSPENDED, any API requests which must access Db2 to complete will be suspended until the RESUME QMGR FACILITY(Db2) command is issued. API requests include:

• The first MQOPEN of a shared queue since the queue manager started
• MQPUT, MQPUT1 and MQGET to or from a shared queue where the message payload has been offloaded to Db2

IMSBRIDGE

Stops the sending of messages from IMS bridge queues to OTMA. The IMS connection is not affected. When the tasks that transmit messages to IMS have been terminated, no further messages are sent to IMS until one of the following actions happens:

• OTMA or IMS is stopped and restarted
• IBM MQ is stopped and restarted
• A RESUME QMGR command is processed

Return messages from IMS OTMA to the queue manager are unaffected.

To monitor progress of the command, issue the following command and ensure that none of the queues are open:

DIS Q(*) CMDSCOPE(qmgr) STGCLASS(bridge_stgclass) IPPROCS

If any queue is open, use DISPLAY QSTATUS to verify that the MQ-IMS bridge does not have it open.

This parameter is valid only on z/OS.

LOG

Suspends logging and update activity for the queue manager until a subsequent RESUME request is issued. Any unwritten log buffers are externalized, a system checkpoint is taken (non-data sharing environment only), and the BSDS is updated with the high-written RBA before the update activity is suspended. A highlighted message (CSQJ372I) is issued and remains on the system console until update activity has been resumed. Valid on z/OS only. If LOG is specified, the command can be issued only from the z/OS system console.

This option is not permitted when a system quiesce is active by either the ARCHIVE LOG or STOP QMGR command.

Update activity remains suspended until a RESUME QMGR LOG or STOP QMGR command is issued.

This command must not be used during periods of high activity, or for long periods of time. Suspending update activity can cause timing-related events such as lock timeouts or IBM MQ diagnostic memory dumps when delays are detected.

CMDSCOPE

This parameter applies to z/OS only and specifies how the command runs when the queue manager is a member of a queue sharing group.

' '

The command runs on the queue manager on which it was entered. This is the default value.

qmgr-name

The command runs on the queue manager you specify, providing the queue manager is active within the queue sharing group.

You can specify a queue manager name, other than the queue manager on which the command was entered, only if you are using a queue sharing group environment and if the command server is enabled.

MODE

Specifies how the suspension of availability is to take effect:

QUIESCE

Other queue managers in the cluster are advised to avoid sending messages to the local queue manager if possible. It does not mean that the queue manager is disabled.

FORCE

All inbound cluster channels from other queue managers in the cluster are stopped forcibly. This occurs only if the queue manager has also been forcibly suspended from all other clusters to which the cluster receiver channel for this cluster belongs.

The MODE keyword is permitted only with CLUSTER or CLUSNL. It is not permitted with the LOG or FACILITY parameter.