Creating the Native HA group if creating your own containers

You must create, configure, and start three queue managers to create the Native HA group.

1. On each of the three nodes, create a queue manager, specifying a log type of log replica, and supplying a unique name for each log instance. Each queue manager has the same name:

   crtmqm -lr instance_name qmname

   For example:

   node 1> crtmqm -lr qm1_inst1 qm1
   
   node 2> crtmqm -lr qm1_inst2 qm1
   
   node 3> crtmqm -lr qm1_inst3 qm1

2. On successful creation of each queue manager, an additional stanza named NativeHALocalInstance is added to the queue manager configuration file, qm.ini. A Name attribute is added to the stanza specifying the supplied instance name.

   You can add optionally add the following attributes to the NativeHALocalInstance stanza in the qm.ini file:

   KeyRepository

   The location of the key repository that holds the digital certificate to use for protection of log replication traffic. The location is given in stem format, that is, it includes the full path and file name without an extension. If the KeyRepository stanza attribute is omitted, log replication data is exchanged between instances in plain text.

   CertificateLabel

   The certificate label identifying the digital certificate to use for protection of log replication traffic. If KeyRepository is provided but CertificateLabel is omitted, a default value of ibmwebspheremqqueue_manager is used.

   CipherSpec

   The MQ CipherSpec to use to protect log replication traffic. If this stanza attribute is provided, KeyRepository must also be provided. If KeyRepository is provided but CipherSpec is omitted, a default value of ANY is used.

   LocalAddress

   The local network interface address that accepts log replication traffic. If this stanza attribute is provided it identifies the local network interface and/or port using the format “[addr][(port)]”. The network address can be specified as a hostname, IPv4 dotted decimal, or IPv6 hexadecimal format. If this attribute is omitted, the queue manager attempts to bind to all network interfaces, it uses the port specified in the ReplicationAddress in the NativeHAInstances stanza matching the local instance name.

   HeartbeatInterval

   The heartbeat interval defines how often in milliseconds an active instance of a Native HA queue manager sends a network heartbeat. The valid range of the heartbeat interval value is 500 (0.5 seconds) to 60000 (1 minute), a value outside of this range causes the queue manager to fail to start. If this attribute is omitted, a default value of 5000 (5 seconds) is used. Each instance must use the same heartbeat interval.

   HeartbeatTimeout

   The heartbeat timeout defines how long a replica instance of a Native HA queue manager waits before it decides that the active instance is unresponsive. The valid range of the heartbeat interval timeout value is 500 (0.5 seconds) to 120000 (2 minutes). The value of the heartbeat timeout must be greater than or equal to the heartbeat interval.

   An invalid value causes the queue manager to fail to start. If this attribute is omitted a replica waits for 2 x HeartbeatInterval before starting the process to elect a new active instance. Each instance must use the same heartbeat timeout.

   RetryInterval

   The retry interval defines how often in milliseconds a Native HA queue manager should retry a failed replication link. The valid range of the retry interval is 500 (0.5 seconds) to 120000 (2 minutes). If this attribute is omitted a replica waits for 2 x HeartbeatInterval before retrying a failed replication link.

3. Edit the qm.ini file for each queue manager and add connection details. You add three NativeHAInstance stanzas, one for each queue manager instance in the Native HA group (including the local instance). Add the following attributes:

   Name

   Specify the instance name that you used when you created the queue manager instance.

   ReplicationAddress

   Specify the hostname, IPv4 dotted decimal or IPv6 hexadecimal format address of the instance. You can specify the address as a hostname, IPv4 dotted decimal, or IPv6 hexadecimal format address. The replication address must be resolvable and routable from each instance in the group. The port number to use for the log replication must be specified in brackets, for example:

   ReplicationAddress=host1.example.com(4444)

   Note: The NativeHAInstance stanzas are identical on every instance and could be provided by using automatic configuration (crtmqm -ii).
4. Start each of the three instances:

   strmqm QMgrName

   When the instances are started they communicate to check that all three instances are running, then decide which of the three is the active instance, while the other two instances continue to run as replicas.

NativeHALocalInstance:
  LocalName=node-1

NativeHAInstance:
  Name=node-1
  ReplicationAddress=host1.example.com(4444)
NativeHAInstance:
  Name=node-2
  ReplicationAddress=host2.example.com(4444)
NativeHAInstance:
  Name=node-3
  ReplicationAddress=host3.example.com(4444)