IBM MQ V9.1 System Administrator key terms

The MQ server process that owns queues, channels, and logs, and provides messaging services to connected applications. It can be started, stopped, and configured independently of other queue managers on the same host.

A queue that physically resides on the queue manager where it is defined and holds messages until an application retrieves them. Its depth and attributes are managed by that queue manager.

A local object that names a destination queue on another queue manager plus the transmission queue and channel used to reach it. It contains no message data itself; it only supplies routing information.

A local queue that temporarily holds messages awaiting transmission over a message channel to a partner queue manager. Messages leave it when the sender channel moves them.

A queue designated to receive messages that cannot be routed or delivered, such as undeliverable messages or those exceeding retry limits. Administrators inspect it to diagnose failures.

A queue named on a local queue where a message is placed after a consuming application repeatedly fails to process it and rolls back. It prevents poison messages from blocking the main queue.

A queue attribute giving the number of times a message may be rolled back before being moved to the backout queue. Zero means no automatic backout handling occurs.

A message that repeatedly causes an application to fail and roll back its unit of work. Without backout configuration, it can cycle indefinitely and stall processing on that queue.

A message channel that initiates a connection to a partner and sends messages taken from a transmission queue. It pairs with a receiver channel on the remote queue manager.

A message channel that passively accepts an inbound connection and places received messages onto the target local queue. It does not initiate connections itself.

A channel type that lets client applications connect to a queue manager over a network using the MQI. It is typically protected by a channel authentication record and TLS settings.

A process that monitors a TCP/IP port and accepts inbound channel connections on behalf of the queue manager. Each port normally maps to one listener object.

The component that moves messages across a message channel, handling batch, sequence, and recovery logic. It runs on behalf of sender and receiver channels.

The current runtime state of a channel, such as running, stopped, retrying, or inactive. Administrators query it to confirm connectivity and diagnose channel failures.

A queue manager component that starts inbound channels on request from a partner queue manager. It must be enabled for channels to be triggered remotely.

A program that reads initiation queues and starts applications or channels when trigger messages arrive. It decouples message arrival from application startup.

A local queue where the queue manager places trigger messages for a trigger monitor to process. It is named in the trigger attributes of the triggering queue.

The queue manager component that processes commands submitted through the command queue, including those issued by runmqsc. It must be running for administrative commands to take effect.

The command-line tool used to administer a queue manager by submitting MQSC commands. It connects to the command server and can run interactively or process a script file.

The text command language used to define and alter queue manager objects such as queues, channels, and authentication records. Commands are submitted through runmqsc or equivalent tooling.

A rule that controls which remote partners may connect to a channel and which user identities they may assert. It blocks or allows connections based on address and user ID patterns.

A queue manager setting that determines whether channel authentication records are enforced. When enabled, connections failing the checks are rejected rather than warned about.

A channel attribute listing the cipher suites permitted for encrypted connections. Both ends must agree on a compatible suite for the TLS handshake to succeed.

The store holding the queue manager's digital certificates and private keys used for TLS. Its location and password are configured at queue manager level.

The name identifying which certificate in the key repository a channel should present. It must be set on channels that use TLS.

A rule granting or revoking object authority, such as connect, inquire, or put, to a principal or group. It forms the basis of queue manager access control.

A named set of authority records applied to a class of objects, such as queues or channels. Profiles simplify administration by grouping permissions.

A user or group identity recognized by the queue manager for authorization decisions. Authority records are granted to principals.

A message marked to survive queue manager restarts because it is written to the log and recovered. Nonpersistent messages may be lost on failure and are not logged.

The attribute controlling whether a message is logged for recovery. It is set by the producing application and influences durability and throughput.

The set of log files recording changes to persistent objects so the queue manager can recover after a failure. Log type and size are set when the queue manager is created.

A logging mode in which log files are preallocated and reused in sequence, requiring media recovery for some failures. It suits high-throughput environments with adequate disk.

A logging mode in which log files are reused in a ring, simplifying administration but limiting recovery options. It is common for smaller or test queue managers.

A named value attached to a message, such as a selector or identity field, that applications and channels can read. Properties extend message headers without changing the body.

The header structure carrying control information for a message, including persistence, priority, and format. Applications and channels read and set these fields.

A filter expression an application supplies when browsing or getting messages, matching against message properties. It lets consumers receive only messages of interest.

The number of messages currently held on a queue. Monitoring it helps detect backlogs and stalled consumers.

A queue manager event generated when a queue's depth exceeds a configured threshold. It supports proactive monitoring of growing backlogs.

A configured object that captures queue manager events, such as channel or queue threshold events, into an event queue for processing. It enables automated monitoring.