Channel properties
The following tables list all the attributes that you can set for all types of channels, including client-connection channels:
Some of the attributes do not apply to all types of channel, some attributes are specific to cluster channels, and some attributes are specific to z/OS® channels.
For each attribute, there is a brief description of when you might need to configure it. The tables also give the equivalent MQSC parameter for the ALTER CHANNEL and DISPLAY CHANNEL commands. For more information about MQSC commands, see Script (MQSC) Commands in the IBM® online IBM WebSphere® MQ product documentation.
General page
The following table lists the attributes that you can set on the General page of the Channel properties dialog.
Attribute | Meaning | MQSC parameter |
---|---|---|
Channel name | Read-only. This is the name of the channel definition. | CHANNEL |
Type | Read-only. This is the type of the channel definition. | CHLTYPE |
QSG disposition | Read-only. This is the queue-sharing group disposition of the
channel definition. You cannot change the disposition of a channel
definition after it has been created. Queue manager means that the object definition is available only to the queue
manager that hosts it; Group means that the object
definition is stored on the shared repository and each queue manager
in the queue-sharing group has a copy of the definition; Copy means that the object definition is the queue manager's copy of
a definition in the shared repository. |
QSGDISP |
Description | Type a meaningful description of the purpose of the channel. See Strings in property dialogs. | DESCR |
Queue manager name | Type the name of the queue manager on which the channel is defined. For client-connection channels, type the name of the queue manager to which an application that is running in the MQI client environment can request connection. | QMNAME |
Transmission protocol | Select from the list the transport type that the channel uses. | TRPTYPE |
Connection name | For all types of channel except cluster-receiver channels,
type the name of the computer that hosts the target queue manager.
The format of the connection name depends on the transmission protocol
that is selected. For example, if you are using the TCP/IP protocol
and you know that the target queue manager is connecting using a port
number other than the IBM WebSphere MQ default of 1414, type computer_name(port_number) , where computer_name is the name or IP address of the computer that hosts the target
queue manager, and port_number is the port that
the target queue manager's listener is using. For cluster-receiver
channels on Windows, UNIX and Linux®, that
use the TCP/IP transport protocol, do not specify a value for this
attribute; IBM WebSphere MQ generates a name for using, assuming the default port and the current
IPv4 address of the system. If the system does not have an IPv4 address,
the current IPv6 address of the system is used. For cluster-receiver
channels on other platforms, and for cluster-receiver channels that
do not use the TCP/IP transport protocol, type the name of the computer
that hosts the local queue manager. |
CONNAME |
Transmission queue | Type the name of the transmission queue that corresponds to the queue manager at the receiver end of the channel. | XMITQ |
Local communication address | If the channel uses TCP/IP and you want the channel to use
a particular IP address, port, or port range for outbound communications,
type the local communications address for the channel. The channel
binds to the address locally. Use the format ipaddress(low-port, high-port), where ipaddress is the IP address
specified in IPv4 dotted decimal, IPv6 hexadecimal, or alphanumeric
host name format. For example, 192.0.2.0 specifies the IPv4 address with any port; 192.0.2.0(1000) specifies the IPv4 address and a specific port; 192.0.2.0(1000,2000) specifies the IPv4 address and a range of ports; (1000) specifies a port only. Cluster-sender channels: If you type a value in the |
LOCLADDR |
Cluster-receiver channels: Do not put an IP address in the |
||
Overall channel status | Read-only. This is the status of the channel. | STATUS |
Extended page
The following table lists the attributes that you can set on the Extended page of the Channel Properties dialog.
Attribute | Meaning | MQSC parameter |
---|---|---|
Maximum message length | Type the maximum length of a message that can be transmitted
on the channel:
|
MAXMSGL |
Heartbeat interval | Type the length of the heartbeat interval, which can be 0 -
999999. A value of zero means that no heartbeat exchange takes place.
Set the value to be less than the value of the Disconnect
interval attribute. The value that is used is the larger
of the values specified at the sending side and the receiving side.
The heartbeat interval is the time, in seconds, between heartbeat
flows passed from the sending MCA when there are no messages on the
transmission queue. The heartbeat exchange gives the receiving MCA
the opportunity to quiesce the channel. |
HBINT |
Maximum instances | This parameter is used on server-connection channels. Maximum instances specifies the maximum number of simultaneous instances of an individual server-connection channel. The value can be a number in the range 0 - 999999999. The default value is 999999999 A value of zero means that all client access is prevented. If Maximum instances is set to a value which is less than the number of instances of the server-connection channel currently running, then new instances are prevented from starting until sufficient existing instances stop running. |
MAXINST |
Maximum instances per client | This parameter is used on server-connection channels. Maximum instances per client specifies the maximum number of simultaneous instances of an individual server-connection channel which can be started from a single client. In this context, connections originating from the same remote network address are regarded as coming from the same client. The value can be a number 0 - 999999999. The default value is 999999999 A value of zero means that all client access is prevented. Maximum instances differs from Maximum instances per client in that Maximum instances is the maximum amount of connections, but Maximum instances per client is the maximum amount of connections that each client is allowed to connect to the server. |
MAXINSTC |
Keep alive interval | Type the length of the keep alive interval, 0 - 99999. This
attribute is ignored if the channel uses a transport type other than
TCP or SPX. The TCP Keep alive attribute must be
set to Yes on the Channels page of the Queue manager
properties. On z/OS queue managers,
the Keep alive interval attribute specifies the keep
alive interval for the individual channel. On queue managers on other
platforms, the Keep alive interval attribute is
used only if the channel connects to a z/OS queue manager;
to use the functionality provided by the Keep alive interval attribute, set the Keep alive interval attribute
to Auto to use a value based on the negotiated
heartbeat interval value. |
KAINT |
Sequence number wrap | The sequence number is the count of messages that are sent through the channel. The sequence number increments each time a message is sent through the channel. Type the highest number, 100 - 999999999 (or, for z/OS using CICS®, 1 - 999999999), that the message sequence number reaches before it restarts at 1. The value must be high enough that the number is not reissued while it is being used by an earlier message. The two ends of the channel must have the same sequence number wrap value when the channel starts; otherwise you get an error. | SEQWRAP |
Non-persistent message speed | To specify that nonpersistent messages on a channel are not transferred within a transaction, select Fast. This means that nonpersistent messages become available for retrieval far more quickly than if they are part of a transaction. However, because the nonpersistent messages are not part of a transaction, they might be lost if, for example, the channel stops while the messages are in transit. To prevent this happening, select Normal. | NPMSPEED |
Batch size | Type the maximum number of messages to be sent before syncpoint is taken. The messages are always transferred individually but are committed or backed out as a batch. Try the default batch size of 50 and change the value only if you need to. | BATCHSZ |
Message compression | Click Edit to open the Edit Message Compression dialog. Select the message compression techniques that are supported by the channel definition in order of preference. The first technique that is supported by the other end of the channel is used. None means that no message compression is performed; RLE means that message data compression is performed using run-length encoding; ZLIBFAST means that message data compression is performed using the zlib compression technique and a fast compression time is preferred; ZLIBHIGH means that message data compression is performed using the zlib compression technique and a high level of compression is preferred; ANY means that any compression technique that is supported by the queue manager can be used. For more information, see Concepts of intercommunication in the IBM online IBM WebSphere MQ product documentation. | COMPMSG |
Header compression | Click Edit to open the Edit Header Compression dialog. Select the header compression techniques that are supported by the channel definition in order of preference. The first technique that is supported by the other end of the channel is used. None means that no header compression is performed; System means that header compression is performed. For more information, see Concepts of intercommunication in the IBM online IBM WebSphere MQ product documentation. | COMPHDR |
Batch interval | Type the number of milliseconds, 0 - 999999999, during which the channel keeps a batch open even if there are no messages on the transmission queue. | BATCHINT |
Batch data limit | Provide the limit in kilobytes, 0 - 999999, of the amount of data that is sent through a channel before taking a sync point. A value of 0 means that no data limit is applied to batches over this channel. | BATCHLIM |
Disconnect interval | Type the number of seconds, 0 - 999999, after the batch ends before the channel closes down. A value of 0 means that the channel does not disconnect. | DISCINT |
Data conversion | To specify that the message is converted by the receiving application to the format that is required on the receiving system (this is the typical method), select No; if the remote queue manager is on a platform that does not support data conversion, select Yes to specify that the message is converted before transmission into the format that is required by the receiving system. | CONVERT |
Put authority | This attribute specifies the type of security processing to be carried out by the Message Channel Agent (MCA) when running an MQPUT command to the target queue or an MQI call. To use the default user ID, click Default; to use the alternate user ID from the context information that is associated with the message, click Context. | PUTAUT |
Batch heartbeat interval | The batch heartbeat interval allows the sending end of the channel to verify that the receiving end of the channel is still active just before the sending end of the channel commits a batch of messages. If the receiving end of the channel is not active, the batch can be backed out rather than becoming in-doubt. By backing out the batch, the messages remain available for processing so that they can, for example, be redirected to another channel. Type the number of seconds, 0 - 999999, that the sending end of the channel waits for a response from the receiving end of the channel before assuming that the receiving end of the channel is inactive. A value of 0 means that batch heartbeating is not used. For more information, see Configuring the channel to reduce the opportunity of being put 'in-doubt'. | BATCHHB |
Default channel disposition | When you issue the START
CHANNEL command without the channel disposition keyword
(CHLDISP), the channel is started using the value of the Default channel
disposition (DEFCDISP). The three possible values are: Private. This is the default value. Start as a private channel on the local queue manager. Shared. A receiving channel is shared if it was started in response to an inbound transmission directed to the queue-sharing group. A sending channel is shared if its transmission queue has a disposition of SHARED. Fix shared. A sending channel is shared if its transmission queue has a disposition of SHARED and the CONNAME is not blank. |
DEFCDISP |
Property control (Only on Sender channels, Server channels, Cluster Sender channels, and Cluster Receiver channels) |
This defines what happens to properties of messages that are about
to be sent to a V6 or earlier queue manager. The value has to be changed
from Compatibility to All to preserve
the v6 behavior of propagating the RFH2 to the caller. The possible
values are: All means that all properties of the message are included with the message when it is sent to the remote queue manager. The properties, except those in the message descriptor (or extension), are placed in one or more MQRFH2 headers in the message data. Compatibility. This is the default value; it allows applications which expect JMS related properties to be in an MQRFH2 header in the message data to continue to work unmodified. If the message contains a property with a prefix of mcd., jms., usr., or mqext. then all optional message properties (where the Support value is MQPD_SUPPORT_OPTIONAL), except those in the message descriptor (or extension) are placed in one or more MQRFH2 headers in the message data before the message is sent to the remote queue manager. Otherwise all properties of the message, except those in the message descriptor (or extension), are removed from the message before the message is sent to the remote queue manager. If the message contains a property where the Support field of the property descriptor is not set to MQPD_SUPPORT_OPTIONAL then the message are rejected and treated in accordance with its report options. If the message contains one or more properties where the Support field of the property descriptor is set to MQPD_SUPPORT_OPTIONAL but other fields of the property descriptor are set to non-default values, then these properties are removed from the message before the message is sent to the remote queue manager. None means that all properties of the message, except those in the message descriptor (or extension), are removed from the message before the message is sent to the remote queue manager. If the message contains a property where the Support field of the property descriptor is not set to MQPD_SUPPORT_OPTIONAL then the message are rejected and treated in accordance with its report options. |
PROPCTL |
Sharing conversations (Only on Server-connection channels and Client-connection channels) |
Specifies the maximum number of conversations
that can be shared over a particular TCP/IP client channel instance
(socket). The possible values are: 0: Specifies
no sharing of conversations over a TCP/IP socket. The channel instance
runs in a mode before that of IBM WebSphere MQ Version 7.0, with regard
to:
1: Specifies no sharing of conversations over a TCP/IP socket. Client heartbeating and read ahead are available, whether in an MQGET call or not, and channel quiescing is more controllable. 2 - 999999999: The number of shared conversations. The default value is 10. If the client-connection SHARECNV value does not match the server-connection SHARECNV value, then the lowest value is used. |
SHARECNV |
Pending reset sequence number | This is the sequence number from an outstanding request and it indicates a user RESET CHANNEL command request is outstanding. A value of zero indicates that there is no outstanding RESET CHANNEL. The value can be in the range 1 - 999999999. When the value of RESETSEQ is 0, the DISPLAY CHANNEL command returns RESETSEQ(NO). |
RESETSEQ |
Use dead-letter queue (Not on Client-connection channels, Server-connection channels, or Telemetry channels) |
Specifies whether the dead-letter
queue is used when messages cannot be delivered by channels. There
are two possible values:
|
USEDLQ |
MCA page
The following table lists the attributes that you can set on the MCA page of the Channel properties dialog. To configure how the Message Channel Agent (MCA) for this channel runs, edit the attributes on the MCA page.
Attribute | Meaning | MQSC parameter |
---|---|---|
MCA user ID | The message channel agent user identifier. If it is nonblank,
it is the user identifier that is to be used by the message channel
agent for authorization to access IBM WebSphere MQ resources, including
(if PUTAUT is DEF) authorization to put the message to the destination
queue for receiver or requester channels. If it is blank, the message
channel agent uses its default user identifier. The default user identifier
is derived from the user ID that started the receiving channel. The
possible values are:
user@domain . |
MCAUSER |
MCA type | To specify that the message channel agent (MCA) program runs as a thread, select Thread; to specify that the MCA runs as a process, select Process. | MCATYPE |
MCA name | Read-only. You cannot edit this attribute because the MCA name is reserved and must only be set to blanks. | MCANAME |
Exits page
The following table lists the attributes that you can set on the Exits page of the Channel properties dialog. To configure the channel to run user exits, edit the attributes on the Exits page.
Attribute | Meaning | MQSC parameter |
---|---|---|
Send exit name | Click Edit to open the Edit Send Exit
Name dialog. Add the names of your send exit programs:
|
SENDEXIT |
Send exit user data | Type the data (maximum 32 characters) to be passed to the channel
send exit when the send exit program is called:
|
SENDDATA |
Receive exit name | Click Edit to open the Edit Receive
Exit Name dialog. Add the names of your receive exit programs:
|
RCVEXIT |
Receive exit user data | Type the data (maximum 32 characters) to be passed to the channel
receive exit when the receive exit program is called:
|
RCVDATA |
Security exit name | Type the name of the security exit program:
|
SCYEXIT |
Security exit user data | Type the data (maximum 32 characters) to be passed to the channel security exit when the channel security exit is called. | SCYDATA |
Message exit name | Click Edit to open the Edit Message
Exit Name dialog. Add the names of your message exit programs:
|
MSGEXIT |
Message exit user data | Type the data (maximum 32 characters) to be passed to the channel
message exit when the channel message exit program is called:
|
MSGDATA |
LU6.2 page
The following table lists the attributes that you can set on the LU6.2 page of the Channel properties dialog. If the channel uses the LU 6.2 transport protocol, edit the attributes on the LU6.2 page.
Attribute | Meaning | MQSC parameter |
---|---|---|
Mode name | Type the LU 6.2 mode name, which is the SNA mode name unless
the value of the Connection name attribute on the General page contains a side-object, in which case leave
the Mode name value blank. The maximum length is
8 characters. |
MODENAME |
TP name | Type the name, or the generic name, of the MCA program that is run at the far end of the link. | TPNAME |
User ID | Type the user identifier that the MCA uses when attempting to initiate a secure LU 6.2 session with a remote MCA. The maximum length is 12 characters; however, only the first 10 characters are used. | USERID |
Password | Click Change channel password, then type in the Change Password dialog the password that the MCA uses when it attempts to initiate a secure LU 6.2 session with a remote MCA. The maximum length is 12 characters. | PASSWORD |
Retry page
The following table lists the attributes that you can set on the Retry page of the Channel properties dialog. To configure how the channel behaves if the channel cannot connect to the remote queue manager, edit the attributes on the Retry page.
Attribute | Meaning | MQSC parameter |
---|---|---|
Short retry count | Type the maximum number of times, 0 - 999999999 (or, for z/OS using CICS, 1 - 999999999), that the channel can try to connect to a remote queue manager. | SHORTRTY |
Short retry interval | Type the approximate interval, in seconds, that the channel must wait before it tries again to connect to the remote queue manager during the short retry count. A value of 0 means that the channel tries again immediately. | SHORTTMR |
Long retry count | Type the maximum number of times, 0 - 999999999, that the channel
can try to connect to a remote queue manager. The value of this attribute
is used only when the count specified in the Short retry count attribute has been exhausted and the channel has still not successfully
connected to the remote queue manager. |
LONGRTY |
Long retry interval | Type the approximate interval, in seconds, that the channel must wait before it tries again to connect to the remote queue manager during the long retry count. A value of 0 means that the channel tries again immediately. | LONGTMR |
Keep alive interval | The value of the Keep alive interval attribute
specifies the time-out value of the channel. To base the keepalive
value on the value of the negotiated heartbeat interval, select Auto. If the negotiated heartbeat interval is greater
than zero, the Keep alive interval is the negotiated
heartbeat interval plus 60 seconds; if the negotiated heartbeat interval
is zero, the Keep alive interval is zero too. To
specify a time-out value, type the number of seconds, 0 - 99999.
To disable KeepAlive on this channel, type 0. |
KAINT |
Message retry page
The following table lists the attributes that you can set on the Message retry page of the Channel properties dialog. To configure how the channel behaves if the channel fails the first time that it tries to put a message on a remote queue, edit the attributes on the Message retry page.
Attribute | Meaning | MQSC parameter |
---|---|---|
Message retry count | Type the number of times, 0 - 999999999, that the channel retries
to deliver a message before it decides that it cannot deliver the
message to the remote queue. This attribute controls the action of
the MCA only if the Message retry exit name attribute
is blank. If the Message retry exit name attribute
is not blank, the value of the Message retry count attribute is passed to the exit for the exit's use but the number
of times that the channel retries to deliver the message is controlled
by the exit, not by the Message retry count attribute. |
MRRTY |
Message retry interval | Type the minimum length of time, in milliseconds, that the channel must wait before it can try again to put the message on the remote queue. | MRTMR |
Message retry exit name | Type the name of the channel message retry exit program:
|
MRDATA |
Message retry exit user data | Type the data (maximum 32 characters) that is passed to the channel message retry exit when the channel message retry exit is called. | MREXIT |
Cluster page
The following table lists the attributes that you can set on the Cluster page of the Channel properties dialog. To share the channel in one or more clusters, edit the attributes on the Cluster page.
Attribute | Meaning | MQSC parameter |
---|---|---|
Not shared in a cluster | By default, this option is selected so that the channel is not shared in any clusters. | Not applicable. |
Shared in cluster | To share the channel in a cluster, select this option, then type the name of the cluster. See Strings in property dialogs. | CLUSTER |
Shared in a list of clusters | To share the channel in more than one cluster, select this option, then type the name of the namelist object that contains the names of the clusters. See Strings in property dialogs. | CLUSNL |
Network priority | The value of this attribute indicates the channel priority for the network connection. Type the value, 0 - 9; 0 is the lowest priority. | NETPRTY |
CLWL channel rank | Type the rank of the channel in the cluster, 0 - 9; 0 is the lowest rank. See also WebSphere MQ Queue Manager Clusters. | CLWLRANK |
CLWL channel priority | Type the priority of the channel in the cluster, 0 - 9; 0 is the lowest priority. See also WebSphere MQ Queue Manager Clusters. | CLWLPRTY |
CLWL channel weight | Type the weighting that is applied to the channel so that the proportion of messages that is sent through the channel is controlled. The value must be 1 - 99; 1 is the lowest weighting. See also WebSphere MQ Queue Manager Clusters. | CLWLWGHT |
SSL page
The following table lists the attributes that you can set on the SSL page of the Channel properties dialog. To configure the channel to use SSL security, edit the attributes on the SSL page.
Attribute | Meaning | MQSC parameter |
---|---|---|
CipherSpec | Type the name (maximum 32 characters) of the CipherSpec for an SSL connection. Both ends of the IBM WebSphere MQ SSL channel definition must have the same value in the CipherSpec attribute. | SSLCIPH |
Accept only certificates with Distinguished Names matching these values | Type the value of the Distinguished Name on the certificate from the peer queue manager or client at the other end of the IBM WebSphere MQ channel. When the channel starts, the value of this attribute is compared with the Distinguished Name of the certificate. | SSLPEER |
Authentication of parties initiating connections | To specify that the channel must receive and authenticate an SSL certificate from an SSL client, select Required; to specify that the channel is not required to receive and authenticate an SSL certificate from an SSL client, select Optional; if you select Optional and the peer SSL client sends a certificate, the channel authenticates the certificate as normal. | SSLCAUTH |
Load Balancing page
The following table lists the attributes that you can set on the Load Balancing page of the Channel properties dialog.
Attribute | Meaning | MQSC parameter |
---|---|---|
Weight | The client channel weighting attribute is used
to specify a weighting to influence which client-connection channel
definition is used. The client channel weighting attribute is used
so that client channel definitions can be selected at random based
on their weighting when more than one suitable definition is available. When a client issues an MQCONN requesting connection to a queue manager group, by specifying a queue manager name starting with an asterisk, and more than one suitable channel definition is available in the client channel definition table (CCDT), the definition to use is randomly selected based on the weighting, with any applicable CLNTWGHT(0) definitions selected first in alphabetical order. Specify a value in the range 0 - 99. The default is 0. A value of 0 indicates that no load balancing is performed and applicable definitions are selected in alphabetical order. To enable load balancing choose a value in the range 1 - 99 where 1 is the lowest weighting and 99 is the highest. The distribution of messages between two or more channels with non-zero weightings is approximately proportional to the ratio of those weightings. |
CLNTWGHT |
Affinity | The channel affinity attribute is used so client
applications that connect multiple times using the same queue manager
name can choose whether to use the same client channel definition
for each connection. Use this attribute when multiple applicable channel
definitions are available. The possible values are: PREFERRED. This is the default value. The first connection in a process reading a client channel definition table (CCDT) creates a list of applicable definitions based on the client channel weight, with any definitions having a weight of 0 first and in alphabetical order. Each connection in the process attempts to connect using the first definition in the list. If a connection is unsuccessful the next definition is used. Unsuccessful definitions with client channel weight values other than 0 are moved to the end of the list. Definitions with a client channel weight of 0 remain at the start of the list and are selected first for each connection. Each client process with the same host name creates the same list. NONE. The first connection in a process reading a CCDT creates a list of applicable definitions. All connections in a process select an applicable definition based on the client channel weight, with any definitions having a weight of 0 selected first in alphabetical order. |
AFFINITY |
Statistics page
The following table lists the attributes that you can set on the Statistics page of the Channel properties dialog. To configure the channel to collect monitoring or statistics data, edit the attributes on the Statistics page.
Attribute | Meaning | MQSC parameter |
---|---|---|
Alteration date | Read-only. This is the date on which the queue attributes were last altered. | ALTDATE |
Alteration time | Read-only. This is the time at which the queue attributes were last altered. | ALTTIME |
Channel monitoring | You can configure IBM WebSphere MQ to collect online
monitoring data about the current performance of the channel. To inherit
the value of the queue manager's Channel monitoring attribute (see Queue manager properties),
click Queue manager. If the queue manager's Channel monitoring attribute is None , the
queue's Channel monitoring attribute is ignored.
If the queue manager's Channel monitoring attribute
is not None : to override the queue manager settings
and prevent data collection for this channel, click Off; to collect data at a low rate, click Low; to collect data at a medium rate, click Medium; to collect data at a high rate, click High. |
MONCHL |
Channel statistics | You can configure IBM WebSphere MQ to collect statistics
data about the activity of the channel. To inherit the value of the
queue manager's Channel statistics attribute (see Queue Manager properties),
click Queue manager. If the queue manager's Channel statistics attribute is None , the
queue's Channel statistics attribute is ignored.
If the queue manager's Channel statistics attribute
is not None : to override the queue manager settings
and prevent data collection for this channel, click Off; to override the queue manager settings and collect data, click On. |
STATCHL |