Message channel agents for queue sharing groups

A channel can only be started on a channel initiator if it has access to a channel definition for a channel with that name.

A message channel agent is an IBM MQ program that controls the sending and receiving of messages. Message channel agents move messages from one queue manager to another; there is one message channel agent at each end of a channel.

A channel definition can be defined to be private to a queue manager or stored on the shared repository and available anywhere (a group definition). This means that a group defined channel is available on any channel initiator in the queue sharing group.

DEFINE CHL(QSG.TO.QM2) CHLTYPE(SDR) +
TRPTYPE(TCP) CONNAME(QM2.MACH.IBM.COM) +
XMITQ(QM2) QSGDISP(GROUP)

DEFINE CHL(QM2.TO.QSG) CHLTYPE(RCVR) TRPTYPE(TCP) +
QSGDISP(GROUP)

There are two perspectives from which to look at the message channel agents used for distributed queuing with queue sharing groups:

Inbound

An inbound channel is a shared channel if it is connected to the queue manager through the group listener. It is connected either through the generic interface to the queue sharing group, then directed to a queue manager within the group, or targeted at the group port of a specific queue manager or the luname used by the group listener.

Outbound

An outbound channel is a shared channel if it moves messages from a shared transmission queue. In the example commands, sender channel QSG.TO.QM2 is a shared channel because its transmission queue, QM2 is defined with QSGDISP(SHARED).