interview q&s mq part 1

8/8/2019 Interview q&s MQ Part 1

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4. Data storage (client): 5 MB.Software Requirements:Operating system: The operating systems supported by WebSphere MQ for AIX, V5.3 are:1. AIX V4.3.3, with PTF U472177, running in a 32 bit environment, on 32 or 64 bit hardware. 2. AIX V5.1, with PTFs U476879, U477366, U477367 and U477368, and APAR fix IY29345 running 32

bit kernel running on 32 or 64 bit hardware.3. AIX V5.1, with PTF U476879, U477366, U477367 and U477368, and APAR fix IY29345 running 64

bit kernel running on 64 bit hardware.Connectivity The network protocols supported by WebSphere MQ for AIX, V5.3 are:1. TCP/IP2. SNA LU 6.2.Databases: DB2 7.1, 7.2Oracle 8i and 9iSybase v12 or v 12.5Java: If you want to use the Java Messaging Support, you need the Java Runtime Environment

Version 1.3 or laterWhat are the software and hardware requirements for installing MQ on Windows?Ans: MQ v 5.3 supports Windows 2000, Windows 2000XP,Windows 2000NT,Windows 2003 SE, Windows 2003EE.Disk Storage: Typical storage requirements are as follows:1 Server installation: 50 MB2. Client installation:15 MB3 Data storage (server): 50 MB4. Data storage (client): 5 MB.Connectivity The network protocols supported by WebSphere MQ for AIX, V5.3 are:1. TCP/IP


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2. SNA LU 6.2.3. LU 6.24. NetBIOSDatabases: DB2 7.1, 7.2Oracle 8i and 9iSybase v12 or v 12.5Java: If you want to use the Java Messaging Support, you need the Java Runtime Environment

Version 1.3 or laterwhat is a Message and what does it contain?Ans: A message is a string of bytes that is meaningful to the applications that use it. Messages areused to transfer information from one application program to another (or between different parts of

the same application). The applications can be running on the same platform, or on different

platforms.WebSphere MQ messages have two parts:1. The application data. The content and structure of the application data is defined by the

application programs that use it.2. A message descriptor.The message descriptor identifies the message and contains additional

control information, such as the type of message and the priority assigned to the message by the

sending application. WebSphere MQ defines the format of the message descriptor. For a completedescription of the message descriptor,What is the Max Length of the message does MQ support/Ans: The default maximum message length is 4 MB, although you can increase this to a maximum

length of100 MB(where 1 MB equals 1 048 576 bytes).What is the difference between Persistent and Non Persistent Messages? Ans: In Web Sphere MQ, messages can be either persistent or non persistent. Persistent messages

are logged and can be recovered in the event of a WebSphere MQ failure. Thus, persistent messages

are guaranteed to be delivered once and only once. Nonpersistent messages are not logged. Web

Sphere still guarantees to deliver them not more than once, but it does not promise to deliver them

once.What is the effect of using Persistant messages?


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Ans: Persistent messages are usually logged. Logging messages reduces the performance of your

application, so use persistent messages for essential data only. If the data in a message can be

discarded if the queue manager stops or fails, use a nonpersistent message.WebSphere MQ messages:Messages are made up of Two parts: Message descriptor, Application dataTypes of messages?Datagram: A Message sent with no response expected.Request: A Message sent for which a response is expected.Reply: A Response Message for a requested message.Report: A Message that describes the occurrence or event

Ex COA/CODSizes ?Qmanager10000 Msgs Maxmsglength4 MbQueue5000 Msgs Maxmsglength4 MbWhat is the attribute used to see the Message length?Ans: MaxMsgLengthWhat is MQ Client?Ans: A Web Sphere MQ clientis a component that allows an application running on a system to issue

MQI calls to a queue manager running on another system. The output from the call is sent back to the

client, which passes it back to the application.What is MQ Server?Ans: A Web Sphere MQ server is a queue manager that provides queuing services to one or more

clients. All the Web Sphere MQ objects, for example queues, exist only on the queue manager

machine (the Web Sphere MQ server machine), and not on the client. A Web Sphere MQ server can

also support local Web Sphere MQApplicationsWhat are the Objects used in Web sphere MQ?Ans: 1. Queue Manager 2. Queues


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3. Channels 4. Processes 5. Name lists.Mention the No ofCharacters required for creating names of the MQ objects?Ans: For MQ Channels it is 20 CharactersFor Remaining objects it is 48 characters.What about is the Default port number for MQ Queue Manager?Ans:1414Difference between MQSC commands and Control commands?MQSC Commands - These commands are used to handle the admin related functions for the

components that are present in the MQ Series. In general MQSC commands are used for creating and

maintaining Message channels, Queue Managers, Clusters etcControl Commands - These commands are used to manage the processes and services that are helpful

in the functioning of the MQ Series. In general these commands are used for Channel listener, Channel

Initiator, Trigger monitor etcIs the MQSC attributes are Case sensitive?Ans: MQSC commands, including their attributes, can be written in uppercase or lowercase. Object

names in MQSC commands are folded to uppercase (that is, QUEUE and queue are not differentiated),

unless the names are enclosed within single quotation marks. If quotation marks are not used, the

object is processed with a name in uppercase.SCRIPT COMMANDS:-After entering in to queue manager we can find script commands.Script commands are same for every queue manager.(These Commands should be used in CAPITAL LETTERS)

DEFINE :-To define/create MQ manager objects like queue,

Channels, process, and listener. ALTER :-to update or modify the existing objects DISPLAY :-to view all the properties of a particular object or to

Display all objects DELETE :-to delete created objects


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CLEAR :-to clear the message from the queue END :-to come out of the queue manager PING :-to check whether other side channel / queue manager is ready to accept our

request. START :- to start the particular channel or listener STOP :-to stop particular channel or listener REFRESH :-used to refresh the security every time after giving or executing, set mgr or

command for queue manager or object RESET :-used to reset channel,cluster,queue manager RESOLVE :-to resolve the channel which is in indoubt state SUSPEND :-to suspend a queue manager from a cluster environment RESUME :-to remove a queue manager from a cluster environment

How can we write the MQSC commands that have too many parameters/Ans: For commands that have too many parameters to fit on one line, use continuation characters to

indicate that a command is continued on the following line:1. A minus sign ( ) indicates that the command is to be continued from the start of _ the following

line.2. A plus sign (+) indicates that the command is to be continued from the first nonblank character on

the following line.What is programmable command format (PCF) commands?These commands are issued from a programme for local or remote administration done by

programmers.What are commands used for creating the Queue manager from the Command prompt?Ans: crtmqm-q -d MY.DEFAULT.XMIT.QUEUE -u DEAD.LETTER.QUEUE QM1Here -q used to define the Queue manager QM1 as a Default Queue manager

-d is used to define the default transmission Queue -u is used to define the default dead letter queue.How can U make the existing Queue Manager as an default Queue Manager?


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Ans: On Windows systems, use the Web Sphere MQ Services snap-in to display the properties of the

queue manager, and check the Make queue manager the default box. You need to stop and restart the

queue manager for the change to take effect.Where are the backup files are present after creating the Queue Manager?Ans: Windows systems: If you use Web Sphere MQ for Windows NT and Windows 2000,configuration information is stored in the Windows Registry.UNIX Systems:1. When you install the product, the Web Sphere MQ configuration file (mqs.ini) is

created. It contains a list of queue managers that is updated each time you create or delete a queue

manager. There is one mqs.ini file per node.2. When you create a new queue manager, a new queue manager configuration file (qm.ini) is

automatically created. This contains configuration parameters for the queue manager.What is the command used for starting the Queue Manager?Ans: strmqmQMNameWhat is the command used for stopping the Queue manager?Ans: endmqm -w QMNameThe command waits until all applications have stopped and the queue manager has ended.endmqm i QMNameThis type of shutdown does not wait for applications to disconnect from the queue manager.Whats the message code for Stopping a Queue Manager?AMQ4044 Queue manager stoppingWhat is the command used to delete the QueueManager?Ans: dltmqmQMNameDisplay the attributes of the Queue Manager QM1?Ans: runmqsc QM1 Display qmgrWhat 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 queuesWhat is the Default max Queue depth?


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Ans5000Types of Queues?Local Queue Remote Queues Alias Queues

Model 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 queueDynamic 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 NameHow can U define Queues in MQ?Ans: Queues are defined to Web Sphere MQ using:

1. The MQSC command DEFINE


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2. The PCF Create Queue commandWhat 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 2GBof SizeHow can u create a Transmission Queue from a local Queue?Ans. Change the usage attribute from normal to TransmissionDefine a Local Queue LQ using the MQSCCommands in the QM QM1Ans: runmqsc QM1

Define 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?


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Ans: 1.First-in-first-out (FIFO).2.Message priority, as defined in the message descriptor. Messages that have the samepriority 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: Aprocess 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 programsWhat 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.


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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 Channels3. 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 Channels

1. Server-connection 2. Client-connectionHow 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 ChannelWhat are the attributes required for the Sender Channel?Ans: 1. The Name of the Channel 4.Transport Type

2. The Connection name 5.ScyexitWhat are different

Channel status?

Ans: Channel Status:1. Inactive 3.Retrying2. Running 4.StoppedWhat about Initializing &Binding states?


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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 receivingchannel 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 downExplain 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 BATCHHEARTBEAT 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, themessages remain available for processing so they could, for example, be redirected to anotherchannel.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.


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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 retrycountnumber 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 ActiveWhat are the three options for stopping channels?

QUIESCE FORCE TERMINATEWhat 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 MCAif 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


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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 Issues

3.QueueManager Stopped 4. Listener is not running 5.TriggerTurned OffExplain 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 ExitTransport-retry ExitWhat 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

is used 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


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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 of1 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 managerfor 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 510Secondary log files: The number of secondary log files to be allocated is 2by default the minimum

is 1 and MAX in Win 252 / Unix 509What is the command used for creating the listener?Ans: crtmqlsr -t tcp -m QMNAME -p portnoWhat is the commands used for running listener in 5.3 Version?Ans: runmqlsr -t tcp -m QMNAME -p portnoWhat is command used to perform task on the MQ services? Ans: amqmdainWhat are commands used on the Command server?Ans: 1.strmqcsv: to start the command server


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2. 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 +allWhat 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.


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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, orpublishes, 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: runmqscQMName

Ping channel (channel name).What are the administrative commands that are used in Publish and Subscribe? Ans: The strmqbrkcommand 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 MYQMGRNAME

The dspmqbrkcommand is used to check the status of the broker. Possible states are: starting,

running, stopping, quiescing, not active and ended abnormally.dspmqbrk -m MYQMGRNAMEThe endmqbrkcommand is used to stop a broker. There are two options:-c requests a controlled

shutdown (default), -i requests an immediate shutdown.-endmqbrk -i -m MYQMGRNAMEWhat 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.


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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 queuedefinition 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 runningDifference 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 InactiveExplain 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.


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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 messagesHow 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.

runmqdlqQNameQMgrName Use 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 messageis 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.


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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 managerExplain 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 runningBackoutCount (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 QueueWhat 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 physicalmessage. 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 used

By trigger monitors, where they are used to identify a group of queues.Namelists are also used with queue manager clusters to maintain a list of clusters referred to bymore than one WebSphere MQ object.The 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


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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 commitHow 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 strmqcsvsaturn.queue.manager where saturn.queue.manager is the QM nameDisplay: dspmqcsv Stop: endmqcsvWhen we use CCSID attribute of the ALTER QMGR command to change the CCSID of the QMwhat 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.


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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 ofthem)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 editorWhen 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)

What is FFST?

First Failure Support Technology For MQSeries for UNIX systems, FFST information is recorded in a file

in the /var/mqm/errors directory. These errors are normally severe, unrecoverable errors, and

indicate either a configuration problem with the system or an MQSeries internal error. The files are

named AMQnnnnn.mm.FDC, where: nnnnn Is the ID of the process reporting the error mm Is a

sequence number, normally 0 When a process creates an FFST record, it also sends a record to syslog.

The record contains the name of the FFST file to assist in automatic problem trackingCreating Damaged Objects Using Log files?1.Rcdmqimg: Use this command to write an image of an object, or group of objects, to the log for use

in media recovery. This command can only be used when using linear logging.Use the associated command rcrmqobj to recreate the object from the image.

2.Rcrmqobj: Use this command to recreate an object, or group of objects, from their images

contained in the log. This command can only be used when using linear loggingUse the associated command, rcdmqimg, to record the object images to the log.Types ofrecovery:

Restart recovery: When you stop WebSphere MQ in a planned way.Crash recovery: When a failure stops WebSphere MQ.Media recovery: To restore damaged objects.


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What are the locations and files of the Error Logging?MQ Series Level ErrorsC:\ProgramFiles\IBM\WebSphere MQ\errors AMQERR01.LOG, AMQERR02.LOG, AMQERR03.LOGQmanager Level errorsC:\ProgramFiles\IBM\WebSphere MQ\Qmgrs\errors AMQERR01.LOG, AMQERR02.LOG,

AMQERR03.LOG\errorsWhat are the different types of security services available in MQ Series?Identification & AuthenticationAccess control The access control service protects critical resources in a system by limiting accessonly to authorized users and their applications.Confidentiality The confidentiality service protects sensitive information from unauthorized disclosureData integrity The data integrity service detects whether there has been unauthorized modification

of data. There are two ways in which data might be altered: accidentally, through hardware and

transmission errors, or because of a deliberate attack, Non-repudiation.Commands ForAuthorization:1.setmqaut: Command used to change the authorizations to a profile, object or class of objects.

Authorizations can be granted to, or revoked from, any number of principals or groups.

2.dspmqaut: Command to display the current authorizations to a specified object. If a user ID is a

member of more than one group, this command displays the combined authorizations of all the

groups.Only one group or principal can be specified.3.dmpmqaut: Command to dump the current authorizations to a specified object.What are the different methods handled by MQ Series for securing a message?Cryptography Message digestsDigital signatures Digital certificatesPublic Key Infrastructure (PKI)


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Cipher Spec: Identifies the combination of the encryption algorithm and MAC algorithm. Both ends of

an SSL connection must agree the same CipherSpec to be able to communicate.What are the steps to be followed in working with SSL on an UNIX environment?1.Setting up a key repository 2.Working with a key repository3.Obtaining personal certificates 4.Managing digital certificates5.Configuring for cryptographic hardware 6.Mapping DNs to user IDs7.Adding personal certificates to a key repositoryWebsphere MQ installation naming consideration?Ensure that the machine name does not contain any spaces. If you insatall in such a machine you

cannot create and Queue managers. Names for userId and group must no longer that 20 charactersWhat is CCSID?

This defines the character set of character data in the message. If you want to set this character set

to that of the queue manager, you can set this field to the constant MQCCSI_Q_MGR or

MQCCSI_INHERIT. When you get a message from a queue, compare the value of the CodedCharSetId

field with the value that your application is expecting. If the two values differ, you might need to

convert any character data in the message or use a data-conversion message exit if one is availableChannel: Communication Paths between Queue Managers.Tell Some Default objects: (43 objects)Queues: SYSTEM.DEFAULT.LOCAL QUEUE SYSTEM.DEFAULT.MODEL.QUEUESYSTEM.DEFAULT.REMOTE.QUEUE SYSTEM.DEFAULT.ALIAS.QUEUESYSTEM.DEFAULT.INITIATION.QUEUE SYSTEM.DEAD.LETTER.QUEUEChannelQueues: SYSTEM.CHANNEL.INITQ SYSTEM.CHANNEL.SYNCQ

Admin Queues: SYSTEM.ADMIN.ACCOUNTING.QUEUE SYSTEM.ADMIN.ACTIVITY.QUEUESYSTEM.ADMIN.COMMAND.QUEUE SYSTEM.ADMIN.STATISTICS.QUEUESYSTEM.ADMIN.TRACE.ROUTE.QUEUEChannels: SYSTEM.AUTO.RECEIVER SYSTEM.AUTO.SVRCONN


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SYSTEM.DEF.CLUSRCVR SYSTEM.DEF.CLUSSDRSYSTEM.DEF.RECEIVER SYSTEM.DEF.REQUESTERSYSTEM.DEF.SENDER SYSTEM.DEF.SERVER

SYSTEM.DEF.SVRCONN Listeners: SYSTEM.DEFAULT.LISTENER.TCPSYSTEM.DEFAULT.LISTENER.SPXSYSTEM.DEFAULT.LISTENER.NETBIOS

SYSTEM.DEFAULT.LISTENER.LU62Process Def: SYSTEM.DEFAULT.PROCESSServices: SYSTEM.DEFAULT.SERVICE SYSTEM.BROKERName Lists: SYSTEM.DEFAULT.NAMELIS

EventQueues: SYSTEM.ADMIN.CHANNEL.EVENT SYSTEM.ADMIN.LOGGER.EVENTSYSTEM.ADMIN.PERFM.EVENT SYSTEM.ADMIN.QMGR.EVENTWhat are advantages of creating Aliases? Why do we create Alias?

When sending messages: Re mapping the queue-manager name when sending messages, Altering or

specifying the transmission queue when sending messages, Determining the destination when

receiving messages, Using a queue manager as a gateway into the cluster. Gives different application

different levels of access authority to the target Queue Allows different applications to work with the

same queue in different way Simplifies maintenance, migration and workload balanceWhat are the parameters required to put a message on a queue (or) putting a message onqueue parameters?Requires a Connection handler (Hconn), a Queue handler (Hobj), a description of the message that

you want to put on the queue (MQMD), Control information, message length, the message data itselfGetting messages for a queue?

You can remove a message from the queue so that other programs can no longer see the message,

you can copy a message, leaving the original message on the queue. This is known as browsing. You

can remove the message once you have browsed it. In both cases, you use the MQGET call, but first


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your application must be connected to the queue manager, and you must use the MQOPEN call to

open the queueWhat happens when a message is put in a PUT-INHIBITED Queue?The messages are put in the dead letter queue. If a channel is unable to put a message to the target

queue because that queue is full or put inhibited, the channel can retry the operation a number oftimes (specified in the message-retry count attribute) at a given time interval (specified in the

message-retry interval attribute). Alternatively, you can write your own message-retry exit that

determines which circumstances cause a retry, and the number of attempts made. The channel goes

to PAUSED state while waiting for the message-retry interval to finishWhat is syncpoints?

Syncpoint coordination is the process by which units of work are either committed or backed out with

data integrity. The decision to commit or back out the changes is taken, in the simplest case, at the

end of a transaction. However, it can be more useful for an application to synchronize data changes at

other logical points within a transaction.

These logical points are called syncpoints (or synchronization points) and the period of processing a

set of updates between two syncpoints is called a unit of workIn-doubt Channels? How will you resolve this ?An in-doubt channel is a channel that is indoubt with the remote channel about which messages has

been sent and receivedSolution: We can do Commit or Rollback the messages which are in doubt.Scenarios:

Queue open failed?*Reason: On an MQCONN or MQCONNX call, the value specified for the QMgrName parameter is not

valid or not known*Resolution: we must correct the configuration information

Queue not found?*Reason Code 2085 MQRC_UNKNOWN_OBJECT_NAME

*Resolution: check for the Queue name in the QManager if not found define it.

Messages sent to DLQ?*Reason code: 2218 Message too big for Channel


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*Investigation: Examine the contents of the dead-letter queue. Each message is contained in a

structure that describes why the message was put to the queue, and to where it was originally

addressed. Also look at previous error messages to see if the attempt to put messages to a dead-

letter queue failed.*Resolution: change the channel size as required, if the channel is a cluster channel then do a

REFRESH cluster so that it will reflect to the other QMs, then reprocess the messageMessage piling(FULL) up in a Queue?*Investigation: Check for the log files (/var/mqm/qmgrs//errors/*.log), The messages

were not being processed because of very high workload.*Resolution: SSL

*Authentication failure:

The SSL client does not have a certificateA certificate has expired or is not yet activeA certificate is not supportedA certificate is corruptedMay be ssl version upgradationChannel refuses to run or channel retry?*Reason: A mismatch of name between a sending and receiving channels, Incorrect channel typespecified, A receiver channel might be in stopped state, the connection might not be defined Correctly,

there might be a problem with communication software.*Resolution: Alter the Queue and REFRESH the cluster to reflect the change in the information stored

in the partial repositoryHandling messages more than 4 MB?Increase the Queue and Queue manager MaxMsgLength attributes, Use segmented messages

(Messages can be segmented by either the application or the Queue manager), use reference

message.DQM: DISTRIBUTED QUEUEING MANAGEMENTSetuping& Controlling of Message Channel in Message Queuing for Q Managers on Distributed

Systems.


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What is the SSL Version used in WMQ5.3?Version 3.0NPMSPEED FAST. What happens if the channel goes down?Nonpersistent message speed (NPMSPEED) It is used to specify the speed at which nonpersistent

messages are to be sent. It can take on two values either normal or fast. The default is fast, which

means that nonpersistent messages on a channel are not transferred within transactions. Non

persistent messages are lost if there is a transmission failure or if the channel stops when the

messages are in transit.What is SSL?Secure Sockets Layer (SSL) is a protocol designed to allow the transmission of secure data over an

insecure network. SSL makes use of digital certificates to enable authentication of the partner. It also

uses encryption to prevent eavesdropping and hash functions to enable detection of tampering. It can

be used with both MCA channels for queue manager to queue manager communication and MQI

channels for client applications connecting to a queue managerWhat are the algorithms in SSL?A CipherSuite is a suite of cryptographic algorithms used by an SSL connection. A suite comprises

three distinct algorithms:The key exchange and authentication algorithm, used during the SSL handshakeThe encryption algorithm, used to encipher the dataThe MAC (Message Authentication Code) algorithm, used to generate the message digestWhat is Triggering?Ans: Web Sphere MQ enables you to start an application automatically when certain conditions on a

queue are met. For example, you might want to start an application when the number of messages on

a queue reaches a specified number. This facility is called triggeringHow many ways of Triggering?EVERY: A trigger event occurs every time that a message arrives on the application queue. Use this

type of trigger if you want a serving program to process only one message, then end.

FIRST: A trigger event occurs only when the number of messages on the application queue changes

from zero to one. Use this type of trigger if you want a serving program to start when the first

message arrives on a queue, continue until there are no more messages to process, then end.

DEPTH: A trigger event occurs only when the number of messages on the application queue reaches

the value of the TriggerDepth attribute.


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What are the Trigger types available Explain?

a.Application triggeringb.Channel Triggeringa) In the case of application triggering the components are Application queue: This is the message

queue associated with an application Process: A process definition defines the application to be used

to process messages from the application queue. Initiation queue: The queue manager moitors theapplication queue. If the trigger type of the application queue is set to Every then whenever a

message is put to the application queue, the q manager looks into the process definition and puts a

message having the application name and other details to the initiation queue Trigger monitor: The

trigger monitor gets the trigger message from the initiation queue and starts the program specified.b) For channel triggering the transmission queue is monitored and when messages are put in the

transmission queue, the q manager puts a message in the channel initiation queue. The channel

initiator is the program which monitors the initiation queue and starts the sender MCA. For the

message to reach the target queue, the channel listener has to be running in the target queue

managerChannel Triggering Conditions:

Trigger ON

Trigger type(first every depth) Trigger data(channel name which is to be fired) Initiation queue(SYSTEM.CHANNEL.INITQ)

Channel Triggering Background process:1. The local queue manager places a message from an application or from a message channel agent

(MCA) on the transmission queue.2. When the triggering conditions are fulfilled, the local queue manager places a trigger message on

the initiation queue.3. The long-running channel initiator program monitors the initiation queue, and retrieves messages

as they appear.4. The channel initiator processes the trigger messages according to information contained in them.

This information may include the channel name, in which case the corresponding MCA is started.5. The channel listener running in the target q mgr starts the receiving MCAApplication Triggering Conditions:

y Trigger ONy Trigger type (first every depth)y Initiation queue (SYSTEM.DEFAULT.INITIATION.QUEUE our own defined local queue)


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y Process (NOTEPAD)DEFINE QLOCAL (LQ) TRIGGER TRIGTYPE (EVERY) INITQ (IQ) PROCESS (NOTEPAD). DEFINE PROCESS (NOTEPAD) APPLICID (NOTEPAD.EXE) APPLTYPE (WINDOWS)Runmqtrm m QM1 q IQBACKGROUND PROCESS:-1. When ever the message comes to triggered local queue, queue manager will fire trigger message

with information called trigger type and the process definition (application which is to be triggered) in

to the initiation queue (IQ) (our own queue).2. At the initiation queue a long running time program called trigger monitor will be watching

(monitoring) the initiation queue.3. Whenever the trigger message occurs in the initiation the trigger monitor will pick the informationand starts the application which is defined in the process.What is a Trigger monitor?

A trigger monitor is a continuously - running program that serves one or more initiation queues. When

a trigger message arrives on an initiation queue, the trigger monitor retrieves the message. The

trigger monitor uses the information in the trigger message. It issues a command to start the

corresponding application/channelWhat is the command used for the running trigger monitor?Ans: On Server side: runmqtrm -m QMName -q Initiation QueueNameOn Client side: runmqtmc -m QMName -q Initiation QueueName

interview q&s mq part 1

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