Question & Answer
Question
You have an IBM MQ multi-instance queue manager and now you want to apply a fix pack level to both hosts and you want to minimize the downtime.
Cause
One of the key benefits for using MQ multi-instance queue managers is that the "downtime" for MQ client applications is minimized when doing maintenance activities on the queue manager (or the host that has the queue manager). This is accomplished by:
- Ending the Active instance with:
endmqm -si QmgrName
The flags -si perform a switchover and allow the reconnectable clients to reconnect.
- Using connectionNameList (via CCDT, MQSERVER, hard coded, etc) with the MQ client application and specify the hostname/IPaddress and port, for both of the instances. This will exploit the automatic client reconnection feature and when the Active is terminated and the switchover takes place, then the MQ client can reconnect to the new Active (previously running as Standby).
- Ending the Active instance with:
endmqm -si QmgrName
The flags -si perform a switchover and allow the reconnectable clients to reconnect.
- Using connectionNameList (via CCDT, MQSERVER, hard coded, etc) with the MQ client application and specify the hostname/IPaddress and port, for both of the instances. This will exploit the automatic client reconnection feature and when the Active is terminated and the switchover takes place, then the MQ client can reconnect to the new Active (previously running as Standby).
Answer
The following is an example of a staged application of fix packs of multi-instance queue managers.
.
The baseline is for MQ 9.3.0.0 LTS installed in both Host-1 (Active) and Host-2 (Standby).
.
The main objective is to upgrade Host-1 as soon as possible to fix pack 9.3.0.4 LTS.
.
Relevant terms
- Active queue manager instance: A queue manager instance that has been started permitting standby instances, and is running.
- Standby queue manager instance: A queue manager instance that has been started permitting standby instances, and is in standby. It is ready to take over from the active instance automatically.
.
Note:
The application of a fix pack within the same version.release is REVERSIBLE, because the application of fix packs does not affect the data structure of the queue manager and you can remove the fix pack to revert back to a previous version.release.fixpack level.
.
a) Assuming that you have the following as a starting point for your migration:
Host-1: MQ 9.3.0.0 (active)
. /opt/mqm/bin/setmqenv -n Installation1
strmqm -x qmgr
.
Host-2: MQ 9.3.0.0 (standby)
. /opt/mqm/bin/setmqenv -n Installation1
strmqm -x qmgr
.
b) Stop the Active instance in Host-1 using the following to do a switchover and allow the reconnectable clients to reconnect:
Host-1: endmqm -si qmgr
.
The baseline is for MQ 9.3.0.0 LTS installed in both Host-1 (Active) and Host-2 (Standby).
.
The main objective is to upgrade Host-1 as soon as possible to fix pack 9.3.0.4 LTS.
.
Relevant terms
- Active queue manager instance: A queue manager instance that has been started permitting standby instances, and is running.
- Standby queue manager instance: A queue manager instance that has been started permitting standby instances, and is in standby. It is ready to take over from the active instance automatically.
.
Note:
The application of a fix pack within the same version.release is REVERSIBLE, because the application of fix packs does not affect the data structure of the queue manager and you can remove the fix pack to revert back to a previous version.release.fixpack level.
.
a) Assuming that you have the following as a starting point for your migration:
Host-1: MQ 9.3.0.0 (active)
. /opt/mqm/bin/setmqenv -n Installation1
strmqm -x qmgr
.
Host-2: MQ 9.3.0.0 (standby)
. /opt/mqm/bin/setmqenv -n Installation1
strmqm -x qmgr
.
b) Stop the Active instance in Host-1 using the following to do a switchover and allow the reconnectable clients to reconnect:
Host-1: endmqm -si qmgr
The Standby instance will become active. Clients that are able to reconnect, will detect the switchover and reconnect to the new Active instance in Host-2.
Host-1: MQ 9.3.0.0 (stopped)
Host-2: MQ 9.3.0.0 (active)
.
c) Apply the fix pack MQ 9.3.0.4 on Host-1.
Host-1: MQ 9.3.0.4 (no instance started yet)
Host-2: MQ 9.3.0.0 (active)
.
d) Start the standby instance in Host-1. Notice that the clients are still connected to the active instance running in Host-2.
Host-1: MQ 9.3.0.4 (standby)
strmqm -x qmgr
Host-2: MQ 9.3.0.0 (active)
.
e) Stop the Active instance in Host-2 to do a switchover and allow the reconnectable clients to reconnect from Host-2 to Host-1.
Host-2: endmqm -si qmgr
Host-1: MQ 9.3.0.0 (stopped)
Host-2: MQ 9.3.0.0 (active)
.
c) Apply the fix pack MQ 9.3.0.4 on Host-1.
Host-1: MQ 9.3.0.4 (no instance started yet)
Host-2: MQ 9.3.0.0 (active)
.
d) Start the standby instance in Host-1. Notice that the clients are still connected to the active instance running in Host-2.
Host-1: MQ 9.3.0.4 (standby)
strmqm -x qmgr
Host-2: MQ 9.3.0.0 (active)
.
e) Stop the Active instance in Host-2 to do a switchover and allow the reconnectable clients to reconnect from Host-2 to Host-1.
Host-2: endmqm -si qmgr
The Standby instance in Host-1 will become active. Clients that are able to reconnect, will detect the switchover and reconnect to the new Active instance in Host-1.
Host-1: MQ 9.3.0.4 (active)
Host-2: MQ 9.3.0.0 (stopped)
.
f) Apply the fix pack MQ 9.3.0.4 on Host-2
Host-1: MQ 9.3.0.4 (active)
Host-2: MQ 9.3.0.4 (no instance started yet)
.
g) Start the standby instance in Host-2. Notice that the clients are still connected to the active instance running in Host-1.
Host-1: MQ 9.3.0.4 (active)
Host-2: MQ 9.3.0.4 (standby)
strmqm -x qmgr
Host-1: MQ 9.3.0.4 (active)
Host-2: MQ 9.3.0.0 (stopped)
.
f) Apply the fix pack MQ 9.3.0.4 on Host-2
Host-1: MQ 9.3.0.4 (active)
Host-2: MQ 9.3.0.4 (no instance started yet)
.
g) Start the standby instance in Host-2. Notice that the clients are still connected to the active instance running in Host-1.
Host-1: MQ 9.3.0.4 (active)
Host-2: MQ 9.3.0.4 (standby)
strmqm -x qmgr
+++ Related technote
https://www.ibm.com/support/pages/node/1284952
Staged migration of MQ multi-instance queue managers
Staged migration of MQ multi-instance queue managers
+++ Related tutorial
https://www.ibm.com/support/pages/node/725975
Installing MQ 9.1.0.0 LTS, applying Fix Pack MQ 9.1.0.1 and uninstalling MQ in Linux RHEL
Installing MQ 9.1.0.0 LTS, applying Fix Pack MQ 9.1.0.1 and uninstalling MQ in Linux RHEL
+++ end +++
[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"ARM Category":[{"code":"a8m0z00000008NKAAY","label":"Components and Features-\u003EHigh Availability (HA)-\u003EMulti Instance Queue Managers"}],"ARM Case Number":"TS003796544","Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"All Version(s)","Line of Business":{"code":"LOB45","label":"Automation"}}]
Was this topic helpful?
Document Information
Modified date:
23 April 2023
UID
ibm16220974