What is Queue?Ans: A queue is a data structure used to store messages. A queue manager owns each queue. The queue manager is responsible for maintaining the queues it owns, and for storing all the messages it receives onto the appropriate queues

What is the Default max Queue depth?Ans 5000

Types of Queues?Local Queue Remote Queues Alias QueuesModel Queue Dynamic Queues Cluster Queues.

Queue: A safe place to store messages for Prior-To-Delivery, it belongs to the Qmgr to which the application is connected.

Model Queue: Model queue is a template of a queue definition that uses when creating a dynamic queue.

Alias Queue: Queue definition, which is Alias to an actual Local or Remote Q. Used for security and easy maintenance.

Remote Queue: Object that defines a Queue belongs to another Q Manager (Logical Def).

Initiation Queue: An initiation queue is a local queue to which the queue manager writes a trigger message when certain conditions are met on another local queue

Dynamic Queue: Such a queue is defined “on the fly” when the application needs it. Dynamic queues may be retained by the queue manager or automatically deleted when the application program ends. Use- To store intermediate results.

Cluster Queue: Custer queue is a local queue that is known throughout a cluster of queue managers.

Reply-To-Queue: A request message must contain the name of the queue into which the responding program must put the Reply Message.

Queue Manager: Provides Messaging services and manages the Queues, Channels, and Processes that belongs to it.

Alias Q Manager: Queue-manager aliases, are created using a remote-queue definition with a blank RNAME.

What are the attributes required for the Remote Queue Definition?Ans: 1.Name of the Queue 2. Transmission Queue Name.3. Remote QueueManager name 4. Remote Local Queue Name

How can U define Queues in MQ?Ans: Queues are defined to Web Sphere MQ using:1. The MQSC command DEFINE2. The PCF Create Queue command

What is Transmission Queue?Ans: Transmission queues are queues that temporarily store messages that are destined for a remote queue manager. You must define at least one transmission queue for each remote queue manager to which the local queue manager is to send messages directly.

What is Initiation Queues?Ans: Initiation queues are queues that are used in triggering. A queue manager puts a trigger message on an initiation queue when a trigger event occurs. A trigger event is a logical combination of conditions that is detected by a queue manager.

What is Dead Letter Queue?Ans: A dead-letter (undelivered-message) queue is a queue that stores messages that cannot be routed to their correct destinations. This occurs when, for example, the destination queue is full. The supplied dead-letter queue is called SYSTEM.DEAD.LETTER.QUEUE. For distributed queuing, define a dead-letter queue on each queue manager involved.

What is the Max size that Queues support in MQ v5.3?Ans.They support around 2GB of Size

How can u create a Transmission Queue from a local Queue?Ans. Change the usage attribute from normal to Transmission

Define a Local Queue LQ using the MQSC Commands in the QM QM1Ans: runmqsc QM1Define qlocal (LQ)

What are the Difference B/W Predefined & Dynamic Queues?Ans: Queues can be characterized by the way they are created:1. Predefined queues are created by an administrator using the appropriate MQSC or PCF commands. Predefined queues are permanent; they exist independently of the applications that use them and survive Web Sphere MQ restarts.2 Dynamic queues are created when an application issues an MQOPEN request specifying the name of a model queue. The queue created is based on a template queue definition, which is called a model queue.

What is the Algorithm followed in retrieving the Messages from the Queue?Ans: 1.First-in-first-out (FIFO).2.Message priority, as defined in the message descriptor. Messages that have the same priority are retrieved on a FIFO basis.3. A program request for a specific message.

What is Process Definition and what are the attributes does it contain?Ans: A process definition object defines an application that starts in response to a trigger event on a WebSphere MQ queue manager. The process definition attributes include the application ID, the application type, and data specific to the application.

What is intercommunication and its components to send message ?What is Intercommunication?Ans: In Web Sphere MQ, intercommunication means sending messages from one Queue manager to another. The receiving queue manager could be on the same machine or another; nearby or on the other side of the world. It could be running on the same platform as the local queue manager, or could be on any of the platforms supported by Web Sphere MQ. This is called a distributed environment.

Message channels Message channel agents

Transmission queues Channel initiators and listeners

Channel-exit programs

What is Distributed Queue Management (DQM).Web Sphere MQ handles communication in a distributed environment such as this using DQM.The local queue manager is sometimes called the source queue manager and the remote queue manager is sometimes called the target queue manager or the partner queue manager.

What is the Objects required for the DQM?Ans: On source QueueManager:1. Transmission Queue 2. Remote queue definition.3. Dead Letter Queue(recommended) 4. Sender ChannelOn Target Queue Manager1. Local Queue 2. Dead Letter Queue 3. Receiver Channel 4.Listenr***.The sender and receiver channels names should be same.

What is channel and mention different types of channels in MQ?Ans: Channels are objects that provide a communication path from one queue manager to another. Channels are used in distributed queuing to move messages from one queue manager to another. They shield applications from the underlying communications protocols. The queue managers might exist on the same, or different, platforms. Different types of Channels:1. Sender-Receiver Channels2. Requester-Server Channels

3. Client Connection channels4. Server Connection Channels.5. Cluster Sender.6. Cluster Receiver Channels

What are MQI channels and there types?MQI channels are the channels that carry messages from MQ Client application to the MQ server and vice versa.They are Bi-directional Channels1. Server-connection 2. Client-connection

How many Channel Combinations?1.Sender-receiver Channel 4.Requester-server Channel2.Requester-sender Channel 5. Server-receiver Channel3.Cluster-Sender- Receiver Channel 6.Client-Server Channel

What are the attributes required for the Sender Channel?Ans: 1. The Name of the Channel 4.Transport Type2. The Connection name 5.Scyexit

What are different Channel status?Ans: Channel Status:1. Inactive 3.Retrying2. Running 4.Stopped

What about Initializing & Binding states?Ans: Before running state first the channel will initializes the listener & Binds with the Receiver Channel then it goes into running mode.

Tell me Some Channel Attributes?Batch Heartbeat Interval (BATCHHB): This heartbeat interval allows a sending channel to verify that the receiving channel is still active just before committing a batch of messages. If the receiving channel is not active, the batch can be backed out rather than becoming in-doubt, Batch interval (BATCHINT), Batch size (BATCHSZ), Channel type (CHLTYPE), Cluster (CLUSTER), Cluster namelist (CLUSNL), Connection name (CONNAME), Convert message (CONVERT), Disconnect interval (DISCINT), Heartbeat interval (HBINT), KeepAlive Interval (KAINT), Long retry count (LONGRTY), Long retry interval (LONGTMR), Maximum message length (MAXMSGL)

Why is Channel RETRYINT attribute used?If a message is places in DLQ because of put inhibited or queue full condition, the DLQ handler attempts to put the message back to the destination queue. This interval is called as RETRYINT by default the retry interval is 60 seconds.Receiver Cluster Receiver Requester

What is channel disconnect interval?This is a time-out attribute, specified in seconds, for the server, cluster-sender, and cluster-receiver channels. The interval is measured from the point at which a batch ends, that is when the batch size is reached or when the batch interval expires and the transmission queue becomes empty. If no messages arrive on the transmission queue during the specified time interval, the channel closes down

Explain the channel attribute BATCHSIZE?BATCHSIZE denotes the maximum number of messages that can be sent through a channel before taking a checkpoint. This parameter is valid only for channels with a channel type (CHLTYPE) of SDR, SVR, RCVR, RQSTR, CLUSSDR, or CLUSRCVR. The value must be in the range 1 through 9999.

What is BATCH HEARTBEAT INTERVAL?Ans: The batch heartbeat interval allows a sending channel to verify that the receiving channel is still active just before committing a batch of messages, so that if the receiving channel is not active, the batch can be backed out rather than becoming in-doubt, as would otherwise be the case. By backing out the batch, the messages remain available for processing so they could, for example, be redirected to another channel.

What is Keep Alive Interval?Ans: The Keep Alive Interval parameter is used to specify a time-out value for a channel. The Keep Alive Interval parameter is a value passed to the communications stack specifying the Keep Alive timing for the channel. It allows you to specify a different keep alive value for each channel. The value indicates a time, in seconds, and must be in the range 0 to 99999.

What is LONG Retry count?Ans: Specify the maximum number of times that the channel is to try allocating a session to its partner. If the initial allocation attempt fails, the short retry count number is decremented and the channel retries the remaining number of times.

What are the ways to start a channel?Use the MQSC command START CHANNELUse the control command runmqchl to start the channel as a processUse the channel initiator to trigger the channelType of channel states:Inactive and Current- Stopped, Starting, Retrying and Active

What are the three options for stopping channels?QUIESCE FORCE TERMINATE

What are the components of message channel?A queue manager to communicate with another queue manager uses message channel. The components of a message channel are1. Sender Message channel agent: Sender MCA is a program that transfers messages from a transmission queue to a communication link2. Receiver MCA: It transfers messages from the communication link into the target queue

3. Communication protocol: Responsible for transferring messages A message channel is unidirectional.

What is Message Channel agent (MCA)?Ans: A message channel agent (MCA) is a program that controls the sending and receiving of messages. There is one message channel agent at each end of a channel. One MCA takes messages from the transmission queue and puts them on the communication link. The other MCA receives messages and delivers them onto a queue on the remote queue manager.A message channel agent is called a caller MCA if it initiated the communication; otherwise it is called a responder MCA.

What is Channel initiator and Listeners?Ans: A channel initiator acts as a trigger monitor for sender channels, because a transmission queue may be defined as a triggered queue. When a message arrives on a transmission queue that satisfies the triggering criteria for that queue, a message is sent to the initiation queue, triggering the channel initiator to start the appropriate sender channel. You can also start server channels in this way if you specified the connection name of the partner in the channel definition. This means that channels can be started automatically, based upon messages arriving on the appropriate transmission queue.You need a listener program to start receiving (responder) MCAs. Responder MCAs are started in response to a startup request from the caller MCA; the channel listener detects incoming network requests and starts the associated channel.

Channel Errors?Due to: 1. Xmitq is set to get disabled 2. Network Issues3.QueueManager Stopped 4. Listener is not running 5.TriggerTurned Off

Explain Channel-Exit programs and what are the types?Channel-exit programs are called at defined places in the processing carried out by MCA programsSecurity Exit: You can use security exit programs to verify that the partner at the other end of a channel is genuineMessage Exit: Message Exit can be used for Encryption on the link, message data conversion, validation of user ID,Message-retry Exit: Message-retry exit is called when an attempt to open the target queue is unsuccessfulSender and receiver Exit: You can use the send and receive exits to perform tasks such as data compression and decompressionChannel auto-definition Exit Transport-retry Exit

What is the Different Logging Methods available?Ans: There are two different types available1. Circular: The circular logging is used for restart recovery. It is the default logging method. Circular isused in Development and Testing Queues. Circular logging keeps all restart Data in a ring of log files. Logging fills the first file in the ring, then moves on to the and so on, until all the files are full. It then goes back to the first file in the ring and starts This continues as long as the product is in use, and has the advantage that you never run out of log files.

2. Linear: Linear logging gives you both restart recovery and media recovery. It is used in Production. Linear logging keeps the log data in a continuous Sequence of files. Space is not reused, so you can always retrieve any record logged from the time that the queue manager was created. As disk space is finite, you might have to think about some form of archiving. It is an administrative task to manage your disk space for the log, reusing Or extending the existing space as necessary.

What is the Default location where the logs are stored and mention the default sizes?Ans: Default location:Windows: C:\Program Files\IBM\WebSphere MQ\log\qmgrUNIX: /var/mqm/log

What is the log file size?Ans: In Web Sphere MQ for Windows NT and Win 2000, the minimum value is 32, and the maximum is 16 384. The default value is 256, giving a default log size of 1 MB.In Web Sphere MQ for UNIX systems, the minimum value is 64, and the maximum is 16 384. The default value is 1024, giving a default log size of 4 MB.

How will you change the log file size?Ans ; You cannot change the log file size. For this you need to drop and re-create the queue manager. The number of log files primary & secondary can be changed but you need to restart the Q manager for the changes to take effect.

what is the number for log primary and secondary file allocated?Ans: Primary log files: The number of primary log files to be allocated is 3 by default the minimum is 2 and MAX in Win 253 / Unix 510

Secondary log files: The number of secondary log files to be allocated is 2 by default the minimum is 1 and MAX in Win 252 / Unix 509

What is the command used for creating the listener?Ans: crtmqlsr -t tcp -m QMNAME -p portno

What is the commands used for running listener in 5.3 Version?Ans: runmqlsr -t tcp -m QMNAME -p portno

What is command used to perform task on the MQ services?Ans: amqmdain

What are commands used on the Command server?Ans: 1.strmqcsv: to start the command server2. dspmqcsv: to display the command server3. endmqcsv: To end the command server.

Is there is any chance for the Message lost?Ans: If the target queuemanager doesn.t contain the dead letter queue defined and if the messages are

running on a fast channel and of non persistant,Then there is a chance of the message loss.

What is the command that is used to provide authorization for the clients?Ans: setmqaut -m QMName -t queue -n Queuename -p GUEST +all

What are the common errors u get in DQM? Explain how to resolve ?Ans: mqrc 2058: MQRC_Q_MGR_NAME_ERRORMqrc 2059: MQRC_Q_MGR_NOT_AVAILABLE.Mqrc 2033: MQRC_NO_MSG_AVAILABLE.Mqrc 2085: MQRC_UNKNOWN_OBJECT_NAME.Mqrc 2009: MQRC_CONNECTION_BROKEN.Mqrc 2043: MQRC_OBJECT_TYPE_ERROR.Mqrc 2086: MQRC_UNKNOWN_OBJECT_Q_MGR.Mqrc 2035: MQRC_NOT_AUTHORIZED.

What are different modes in which a application can connect to a Queuemanager?Ans: 1.Binding mode: In binding mode, also known as server connection, the communication to the queue manager utilizes inter-process communications. One of the key factors that should be kept in mind is that binding mode is available only to programs running on the MQSeries server that hosts the queue manager. A program using binding mode will not run from an MQSeries client machine. Binding mode is a fast and efficient way to interact with MQSeries. Certain Facilities, such as XA transaction co-ordination by queue manager, are available only in binding mode.2. Client Connection: Client connection uses a TCP/IP connection to the MQSeries Server and enables communications with the queue manager. Programs using client connections can run on an MQSeries client machine as well as on an MQSeries server machine. Client connections use client channels on the queue manager to communicate with the queue manager. The client connection does not support XA transaction coordination by the queue manager.

What are the different types of messaging systems used by JMS?Ans: JMS applications use either the point-to-point (PTP) or publish/subscribe style of messaging.Point-to-Point: Point-to-point messaging involves working with queues of messages. The sender sends messages to a specific queue to be consumed normally by a single receiver. In point-to-point communication, a message has at most one recipient. A sending client addresses the message to the queue that holds the messages for the intended (receiving) client.Publish/Subscribe: In contrast to the point-to-point model of communication, the publish/subscribe model enables the delivery of a message to multiple recipients. A sending client addresses, or publishes, the message to a topic to which multiple clients can be subscribed. There can be multiple publishers, as well as subscribers, to a topic.

Is It Possible to use one transmission Queue for the multiple message channels?Ans: It is possible to define more than one channel per transmission queue, but only one of these channels can be active at any one time. This is recommended for the provision of alternative routes between queue managers for traffic balancing and link failure corrective action. A transmission queue cannot be used by another channel if the previous channel to use it terminated leaving a batch of messages in-doubt at the sending end.

What is the command used to test whether the channel is active or not?

Ans: runmqsc QMNamePing channel (channel name).

What are the administrative commands that are used in Publish and Subscribe?Ans: The strmqbrk command is used to start a broker. The first time this command is run on a queue manager, all the relevant MQSeries objects are automatically created.

——–strmqbrk -m MYQMGRNAMEThe dspmqbrk command is used to check the status of the broker. Possible states are: starting, running, stopping, quiescing, not active and ended abnormally.

——–dspmqbrk -m MYQMGRNAMEThe endmqbrk command is used to stop a broker. There are two options: -c requests a controlled shutdown (default), -i requests an immediate shutdown.

——-endmqbrk -i -m MYQMGRNAME

What is multiple hoping?Ans: If there is no direct communication link between the source queue manager and the target queue manager, it is possible to pass through one or more intermediate queue managers on the way to the target queue manager. This is known as a multi-hop.

What is Local administration and Remote administration?Local Administration: Means carrying out administration tasks on any queue managers you have defined on your local system.Remote Administration: This allows you to issue commands from your local system that are processed on another system. For example, you can issue a remote command to change a queue definition on a remote queue manager. You do not have to log on to that system, although you do need to have the appropriate channels defined. The queue manager and command server on the target system must be running

Difference between Control Commands used in Windows and other Os?Control commands on are case sensitive other OS but Windows they can be used any way.

What is MQOO_BIND_ON_OPEN option on the MQOPEN call ?When this attribute is set it forces all the messages sent to this queue to be sent to the same instance of the queue (go to the same queue in cluster)

Difference between MQPUT and MQPUT1 call ?The MQPUT1 call always operates as though MQOO_BIND_NOT_FIXED were in effect, that is, it always

invokes the workload management routine.

When is Channel security exit program called?Are called at MCA initiation and terminationStopping unauthorized queue managers putting messages on your queuesUse OS security, Object Authority Manager (OAM) on WebSphere MQ user-written procedures

What happens if DEAD letter Queue is not defined?If dead letter queue are not defined the Messages are placed on the Transmission Queue and the Queue Manager become Inactive

Explain Remote queue definitions? Advantages?These are definitions for queues that are owned by another queue managerAdvantages: The advantage of remote queue definitions is that they enable an application to put a message to a remote queue without having to specify the name of the remote queue or the remote queue manager, or the name of the transmission queue. This gives you location independence.

What happens if channel terminates when fast non-persistent messages are in transit?If a channel terminates while fast, non-persistent messages are in transit, the messages are lost and it is up to the application to arrange for their recovery if required. If the receiving channel cannot put the message to its destination queue then it is placed on the dead letter queue, if one has been defined. If not, the message is discarded.

What happens when a message cannot be delivered?Message-retry: If the MCA is unable to put a message to the target queue for a reason that could be transitory (for example, because the queue is full), the MCA has the option to wait and retry the operation laterReturn-to-sender: If message-retry was unsuccessful, or a different type of error was encountered, the MCA can send the message back to the originatorDead-letter queue: If a message cannot be delivered or returned, it is put on to the dead-letter queue (DLQ). You can use the DLQ handler to process the messageRecovery scenario –Disk Drive Full, damaged Queue manager object, Damaged single object, Automatic media recovery failureMQ ensures that messages are not lost by maintaining records (logs) of the activities of the queue managers that handle the receipt, transmission, and delivery of messages

How to Process Messages from the Dead-letter-Queue?We can Process the DLQ messages using runmqdlq command for sending messages to the destination Queues or target Queues. Use the runmqdlq command to start the dead-letter queue (DLQ) handler, which monitors and handles messages on a dead-letter queue.runmqdlq QName QMgrNameUse the Dead-Letter-Queue-Handler to perform various actions on selected messages by specifying a set of rules that can both select a message and define the action to be performed on that message.

The runmqdlq command takes its input from stdin. When the command is processed, the results and a summary are put into a report that is sent to stdout.

Which field of the MQDLH structure contains a reason code that identifies why the message is on the DLQ?Reason fieldWhat is completion code(MQCC) and reason code(MQRC)?Completion code gives the status of the current transaction it can be 0, 1, 2. 0- for Successful completion (MQCC_OK), 1- Warning (MQCC_WARNING), 2- call failed (MQCC_FAILED). Reason code is that which gives the reason for which the transaction fails it can be MQRC_NONE, MQRC_BACKED_OUT etc.

What is Correl ID?This is a byte string that the application can use to relate one message to another, or to relate the message to other unit of work that the application is performing. The correlation identifier is a permanent property of the message, and persists across restarts of the queue manager

Explain commit and Back Out units of work?When a program puts a message on a queue within a unit of work, that message is made visible to other programs only when the program commits the unit of work.Commit: To commit a unit of work, all updates must be successful to preserve data integrity. If the program detects an error and decides that the put operation should not be made permanent, it can back out the unit of work.Back Out: When a program performs a back out, WebSphere MQ restores the queue by removing the messages that were put on the queue by that unit of work. The way in which the program performs the commit and back out operations depends on the environment in which the program is running

BackoutCount (MQLONG)?This is a count of the number of times that the message has been previously returned by the MQGET call as part of a unit of work, and subsequently backed out. BackoutCount is the number of times the application tried and failed to put the messages in the Queue

What is segmentation and explain segmentation Flag?When a message is too big for a queue, an attempt to put the message on the queue usually fails. Segmentation is a technique whereby the queue manager or application splits the message into smaller pieces called segments, and places each segment on the queue as a separate physical message. The application that retrieves the message can either retrieve the segments one by one, or request the queue manager to reassemble the segments into a single message that is returned by the MQGET call.

What are Namelist? when do you use it?A namelist is a WebSphere MQ object that contains a list of other WebSphere MQ objects. Typically, namelists are usedàBy trigger monitors, where they are used to identify a group of queues.àNamelists are also used with queue manager clusters to maintain a list of clusters referred to by more

than one WebSphere MQ object.àThe advantage of using a namelist is that it is maintained independently of applications; it can be updated without stopping any of the applications that use it. Also, if one application fails, the namelist is not affected and other applications can continue using it. Namelists are also used with queue manager clusters to maintain a list of clusters referred to by more than one WebSphere MQ object

What are name services?The name service is an installable service that provides support to the queue manager for looking up the name of the queue manager that owns a specified queue.

What is Local units of work (uses a single-phase commit process) and Global unit of Work (uses a two-phase commit process)?Local unit of work: Units of work that involve only the queue manager are called local units of work. Syncpoint coordination is provided by the queue manager itself (internal coordination) using a single-phase commit process.Use global units of work when you also need to include updates to resources belonging to other resource managers. Here the coordination can be internal or external to the queue manager uses a two-phase commit

How will we start a command server?Depending on the value of the queue manager attribute, SCMDSERV, the command server is either started automatically when the queue manager starts, or must be started manually.Start: Using strmqcsv saturn.queue.manager where saturn.queue.manager is the QM nameDisplay: dspmqcsv Stop: endmqcsv

When we use CCSID attribute of the ALTER QMGR command to change the CCSID of the QM what are the components that need to be restarted?Stop and restart the queue manager, stop and restart command server (A command server processes command messages) and channel programs

What is a MQ Series Queue manager Configuration file (qm.ini)?A queue manager configuration file (qm.ini) to effect changes for specific queue managers. There is one qm.ini file for each queue manager on the node. (A queue manager configuration file, qm.ini, contains config information relevant to a specific queue manager. There is one queue manager configuration file for each queue manager. The qm.ini file is automatically created when the queue manager with which it is associated is created. For example, the path and the name for a configuration file for a queue manager called QMNAME is:/var/mqm/qmgrs/QMNAME/qm.ini)

What is name transformation in naming a Queue manager Configuration File?A qm.ini file is held in the root of the directory tree occupied by the queue manager. For example, the path and the name for a configuration file for a queue manager called QMNAME is: /var/mqm/qmgrs/QMNAME/qm.ini A directory name is generated based on the queue manager name. This process is known as name transformation.

What is a Websphere MQ configuration file (mqs.ini)?Contains information relevant to all the queue managers on the node. It is created automatically during installation (The WebSphere MQ configuration file, mqs.ini, contains information relevant to all the queue managers on the node. It is created automatically during installation. The mqs.ini file for WebSphere MQ for UNIX systems is in the /var/mqm directory. It contains: v The names of the queue managers v The name of the default queue manager The location of the files associated with each of them)

How can we edit the configuration files?Automatically using commands that change the configuration of queue managers on the node, Manually using a standard text editor

When security checks are made?Connecting to the queue manager (MQCONN or MQCONNX calls), Opening the object (MQOPEN or MQPUT1 calls), Putting and getting messages (MQPUT or MQGET calls), Closing the object (MQCLOSE)