The broker stops accepting new client connections on the paused service. If a Message Queue client attempts to open a new connection, it will get an exception.
All existing connections on the paused service are kept alive, but the broker suspends all message processing on such connections until the service is resumed. (For example, if a client attempts to send a message, the send method will block until the service is resumed.)
The message delivery state of any messages already received by the broker is maintained. (For example, transactions are not disrupted and message delivery will resume when the service is resumed.)
The admin connection service can never be paused; to pause and resume any other service, use the subcommands imqcmd pause svc and imqcmd resume svc. The syntax of the imqcmd pause svc subcommand is as follows:
imqcmd pause svc -n serviceName [-b hostName:portNumber]
For example, the following command pauses the httpjms service running on the default broker (host localhost at port 7676):
imqcmd pause svc -n httpjms -u admin
imqcmd resume svc -n serviceName [-b hostName:portNumber]