Use this task to identify and resolve locked messages,
which are messages that are currently unavailable to a message consumer
or browser accessing a message point.
About this task
Under
normal circumstances, a message is locked for a relatively short period
by another messaging application and is either then removed or made
available to the message point (that is, unlocked). However, there
are a number of ways in which a message can remain locked for long
periods and in this case you might need to take action to resolve
the locked message.
To find and resolve locked messages on a
message point, use the administrative console to complete the following
steps.
Procedure
- To find any locked messages, List the messages
on the message point. The State property
indicates whether or not a message is locked.
- To display extra information about a message, click its
name in the list. This displays the Messages [Settings] panel, which shows a range of properties of the
message, for example:
- Time stamp
- The time stamp of the message.
- Message wait time
- The time the message has been waiting to be consumed.
- If a message has remained locked for a long period, determine
whether you need to take action to resolve it:
- If a transaction ID is displayed with the message, this indicates
that the message is either being consumed or produced under the transaction
identified. If the message is being consumed, it is possible that
the consuming application has failed to commit the transaction which
will leave the message in this state until the transaction manager
times out the transaction and rolls back the consumption of the message.
It is also possible, although less likely, that the transaction has
become in-doubt, in which case you might need to take action to resolve
it. See Resolving indoubt transactions for
further information.
- If no transaction ID is displayed, the message is probably
currently assigned to a consuming application connected to another
messaging engine in the bus. In this situation, the message is listed
under one of this message point's known remote message points as a
current message request. If the remote messaging engine identified
in the known remote message point is currently unavailable, messages
stay locked to it until the messaging engine becomes available again.
Check the state of the remote messaging engine to ensure that it is
started and communicating with the message point's messaging engine.
What to do next
If appropriate, after resolving one or more locked messages,
you can delete these messages on the
Messages [Collection] panel.