ALTER COMMINFO

Use the MQSC command ALTER COMMINFO to alter the parameters of a communication information object.


Use MQSC commands

For information on how we use MQSC commands, see Performing local administration tasks using MQSC commands.

Parameters not specified in the ALTER COMMINFO command result in the existing values for those parameters being left unchanged.

We can issue this command from sources 2CR. For an explanation of the source symbols, see Use commands on z/OS®.

Synonym: ALT COMMINFO

ALTER COMMINFO

ALTER COMMINFO ( comminfo name ) BRIDGE(DISABLED)BRIDGE(ENABLED)CCSID(ASPUB)CCSID(codepage)COMMEV(DISABLED)COMMEV(ENABLED)COMMEV(EXCEPTION)DESCR(' ')ENCODING(ASPUB)ENCODING(NORMAL)ENCODING(REVERSED)ENCODING(S390)ENCODING(TNS)ENCODING(encoding)GRPADDR(group address)MCHBINT(heartbeat interval)MCPROP(ALL)MCPROP(REPLY)MCPROP(USER)MCPROP(NONE)MCPROP(COMPAT)MONINT(monitor interval)MSGHIST(message history)NSUBHIST(NONE)NSUBHIST(ALL)PORT(port number)Notes:


Parameter descriptions for ALTER COMMINFO

    (comminfo name)
    Name of the communications information object. This parameter is required.

    The name must not be the same as any other communications information object name currently defined on this queue manager. See Rules for naming IBM MQ objects.

    BRIDGE
    Controls whether publications from applications not using Multicast are bridged to applications using Multicast. Bridging does not apply to topics that are marked as MCAST(ONLY). As these topics can only be Multicast traffic, it is not applicable to bridge to the queue's publish/subscribe domain.

      DISABLED
      Publications from applications not using Multicast are not bridged to applications that do use Multicast.
      ENABLED
      Publications from applications not using Multicast are bridged to applications that do use Multicast.

    CCSID(integer)
    The coded character set identifier that messages are transmitted on. Specify a value in the range 1 through 65535.

    The CCSID must specify a value that is defined for use on your platform, and use a character set that is appropriate to the queue manager's platform. If we use this parameter to change the CCSID, applications that are running when the change is applied continue to use the original CCSID therefore you must stop and restart all running applications before you continue. Running applications include the command server and channel programs. Stop and restart all running applications, stop and restart the queue manager after changing this parameter.

    The CCSID can also be set to ASPUB, which means that the coded character set is taken from that supplied in the published message.

    COMMEV
    Controls whether event messages are generated for Multicast handles that are created using this COMMINFO object. Events are only generated if they are enabled using the MONINT parameter.

      DISABLED
      Publications from applications not using Multicast are not bridged to applications that do use Multicast.
      ENABLED
      Publications from applications not using Multicast are bridged to applications that do use Multicast.
      EXCEPTION
      Event messages are written if the message reliability is below the reliability threshold. The reliability threshold is set to 90 by default.

    DESCR(string)
    Plain-text comment. It provides descriptive information about the communication information object when an operator issues the DISPLAY COMMINFO command (see DISPLAY COMMINFO on Multiplatforms).

    It must contain only displayable characters. The maximum length is 64 characters. In a DBCS installation, it can contain DBCS characters (subject to a maximum length of 64 bytes).

    Note: If characters are used that are not in the coded character set identifier (CCSID) for this queue manager, they might be translated incorrectly if the information is sent to another queue manager.

    ENCODING
    The encoding that the messages are transmitted in.

      ASPUB
      The encoding of the message is taken from that supplied in the published message.
      NORMAL
      REVERSED
      S390
      TNS
      encoding

    GRPADDR
    The group IP address or DNS name.

    It is the responsibility of the administrator to manage the group addresses. It is possible for all multicast clients to use the same group address for every topic; only the messages that match outstanding subscriptions on the client are delivered. Using the same group address can be inefficient because every client has to examine and process every multicast packet in the network. It is more efficient to allocate different IP group addresses to different topics or sets of topics, but this allocation requires careful management, especially if other non-MQ multicast applications are in use on the network.

    MCHBINT
    The heartbeat interval is measured in milliseconds, and specifies the frequency at which the transmitter notifies any receivers that there is no further data available.

    MCPROP
    The multicast properties control how many of the MQMD properties and user properties flow with the message.

      All
      All user properties and all the fields of the MQMD are transported.
      Reply
      Only user properties, and MQMD fields that deal with replying to the messages, are transmitted. These properties are:

      • MsgType
      • MessageId
      • CorrelId
      • ReplyToQ
      • ReplyToQmgr
      User
      Only the user properties are transmitted.
      NONE
      No user properties or MQMD fields are transmitted.
      COMPAT
      This value causes the transmission of the message to be done in a compatible mode to RMM allowing some inter-operation with the current XMS applications and Broker RMM applications.

    MONINT( integer )
    How frequently, in seconds, that monitoring information is updated. If events messages are enabled, this parameter also controls how frequently event messages are generated about the status of the Multicast handles created using this COMMINFO object.

    A value of 0 means that there is no monitoring.

    MSGHIST
    The maximum message history is the amount of message history that is kept by the system to handle retransmissions in the case of NACKs (negative acknowledgments).

    A value of 0 gives the least level of reliability.

    NSUBHIST
    The new subscriber history controls whether a subscriber joining a publication stream receives as much data as is currently available, or receives only publications made from the time of the subscription.

      NONE
      A value of NONE causes the transmitter to transmit only publication made from the time of the subscription.
      ALL
      A value of ALL causes the transmitter to retransmit as much history of the topic as is known. In some circumstances, this retransmission can give a similar behavior to retained publications. Note: Using the value of ALL might have a detrimental effect on performance if there is a large topic history because all the topic history is retransmitted.

    PORT(integer)
    The port number to transmit on.