Managing message queues

You can manage your message queues in several ways.

The operations you can use to manage your message queues include:

Create message queues.
Change the attributes of message queues.
Change the message queue for a printer.
Print all messages in the message queue.

The following details show how these examples can be implemented using message queues.

A small-sized customer has one LAN line and few users: No changes need to be made. All messages remain in the QSYSOPR message queue or in the configured message queue.
A medium-sized customer has a couple of LAN lines: In this instance, you need to change QCFGMSGQ (the message queue for lines, controllers and devices) system value to the system-supplied message queue, QSYS/QCFGMSGQ. As a result, all communications messages for the object types that support the MSGQ configuration parameter go to this queue.
A large-sized customer has many LAN lines and many WAN lines, with many users on each line. You want to set up the message queues so that the messages are separated in the following ways:
- The messages for the Ethernet LAN go to the ETHMSGQ message queue: On this line, the system configures all the controllers automatically.
- The messages for the token-ring LAN go to the TRNMSGQ message queue: On this line, the system configures most controllers; however, some controllers must be configured manually.
- All messages for workstation users go to the WSMSGQ message queue: This includes local workstations, remote workstations, pass-through, and Telnet.
- All other communications messages go to the QCFGMSGQ message queue.

You are an experienced operator who has written a program that helps the operator know which message queues are important. Here is how to configure this example:
- Change the system value QCFGMSGQ to QSYS/QCFGMSGQ.
- Create the Ethernet line description with the MSGQ(ETHMSGQ) parameter value: The system creates all controllers (and thus devices) on this line. This means the system sends its messages to the message queue defined in the line ETHMSGQ.
- Create the token-ring line description with the MSGQ(TRNMSGQ) parameter value: Messages for the created controllers and devices on this line are sent to the TRNMSGQ message queue. Controllers that are manually created on this line are created with the MSGQ(TRNMSGQ) parameter value.
- Create the X.25 line description with the MSGQ(V25MSGQ) parameter value: All controllers that are created for this X.25 line description must be created using the MSGQ(X25MSGQ) parameter value on the CRTCTLxxx command.
- You can set up the workstation controller descriptions in the following ways:
  - Change the local workstation controller description, which the system automatically created, to the MSGQ(WSMSGQ) parameter value.
    Notes:
    1. Create all printer devices attached to the workstation controller with the MSGQ(*CTLD) parameter value. Messages for display devices always go to the message queue that is defined in the associated controller. Thus, changing the message queue of the controller causes the messages for the devices to go to the message queue that is defined in the controller description.
    2. It is possible for the user to use the Change Command Default (CHGCMDDFT) command and change the default value of the message queue. This means that the automatic creation of the local workstation controller uses a different message queue.
  - Create the virtual controllers for pass-through and Telnet with the MSGQ(WSMSGQ) parameter value.
    Like the local workstation controllers, the messages for devices attached to the virtual workstation controllers are sent to the queue defined in the virtual controller. The same logic works for the remote workstation controllers and their attached devices.
A large-sized customer that is now using TCP/IP only, and you want to have the line and workstation messages logged to the QTCP message queue: You can manage this configuration by changing the system value QCFGMSGQ to QSYS/QTCP.