Channel attributes

This section describes the channel attributes held in the channel definitions.

You choose the attributes of a channel to be optimal for a particular set of circumstances for each channel. However, when the channel is running, the actual values might have changed during startup negotiations. See Preparing channels.

Many attributes have default values, and you can use these values for most channels. However, in those circumstances where the defaults are not optimal, see this section for guidance in selecting the correct values.

Note: In IBM® MQ for IBM i, most attributes can be specified as *SYSDFTCHL, which means that the value is taken from the system default channel in your system.

The channel types for IBM MQ channel attributes are listed in the following table, in the order of the MQSC command parameters.

Note: For cluster channels (the CLUSSDR and CLUSRCVR columns in the table), if an attribute can be set on both channels, set it on both and ensure that the settings are identical. If there is any discrepancy between the settings, those that you specify on the CLUSRCVR channel are likely to be used. This is explained in Cluster channels.

Table 1. Channel attributes for the channel types
Attribute field	MQSC command parameter	SDR	SVR	RCVR	RQSTR	CLNT- CONN	SVR- CONN	CLUS- SDR	CLUS- RCVR	AMQP
Connection Affinity	AFFINITY					Yes
Alter date	ALTDATE	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Alter time	ALTTIME	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
AMQP keep alive	AMQPKA									Yes
Batch heartbeat interval	BATCHHB	Yes	Yes					Yes	Yes
Batch interval	BATCHINT	Yes	Yes					Yes	Yes
Batch limit	BATCHLIM	Yes	Yes					Yes	Yes
Batch size	BATCHSZ	Yes	Yes	Yes	Yes			Yes	Yes
Certificate label	CERTLABL	Yes	Yes	Yes	Yes	Yes	Yes	Yes ¹	Yes	Yes
Channel name	CHANNEL	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Channel type	CHLTYPE	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Client channel weight	CLNTWGHT					Yes
Cluster namelist	CLUSNL							Yes	Yes
Cluster	CLUSTER							Yes	Yes
Cluster workload priority	CLWLPRTY							Yes	Yes
Cluster workload rank	CLWLRANK							Yes	Yes
Cluster workload weight	CLWLWGHT							Yes	Yes
Header compression	COMPHDR	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Data compression	COMPMSG	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Connection name	CONNAME	Yes	Yes		Yes	Yes		Yes	Yes
Convert message	CONVERT	Yes	Yes					Yes	Yes
Default reconnection	DEFRECON					Yes
Description	DESCR	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Disconnect interval	DISCINT	Yes	Yes				Yes No	Yes	Yes
Heartbeat interval	HBINT	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Keepalive interval	KAINT	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Local address	LOCLADDR	Yes	Yes		Yes	Yes		Yes	Yes	Yes
Long retry count	LONGRTY	Yes	Yes					Yes	Yes
Long retry interval	LONGTMR	Yes	Yes					Yes	Yes
Maximum instances	MAXINST						Yes			Yes
Maximum instances per client	MAXINSTC						Yes
Maximum message length	MAXMSGL	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Message channel agent name	MCANAME	Yes	Yes		Yes			Yes	Yes
Message channel agent type	MCATYPE	Yes	Yes		Yes			Yes	Yes
Message channel agent user	MCAUSER	Yes	Yes	Yes	Yes		Yes	Yes	Yes	Yes
LU 6.2 mode name	MODENAME	Yes	Yes		Yes	Yes		Yes	Yes
Monitoring	MONCHL	Yes	Yes	Yes	Yes		Yes	Yes	Yes
Message-retry exit user data	MRDATA			Yes	Yes				Yes
Message-retry exit name	MREXIT			Yes	Yes				Yes
Message retry count	MRRTY			Yes	Yes				Yes
Message retry interval	MRTMR			Yes	Yes				Yes
Message exit user data	MSGDATA	Yes	Yes	Yes	Yes			Yes	Yes
Message exit name	MSGEXIT	Yes	Yes	Yes	Yes			Yes	Yes
Network-connection priority	NETPRTY								Yes
Nonpersistent message speed	NPMSPEED	Yes	Yes	Yes	Yes			Yes	Yes
Password	PASSWORD	Yes	Yes		Yes	Yes		Yes
Port number	PORT									Yes
PROPCTL channel options for MQGMO	PROPCTL	Yes	Yes					Yes	Yes
PUT authority	PUTAUT			Yes	Yes		Yes No		Yes
Queue manager name	QMNAME					Yes
Disposition	QSGDISP	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Receive exit user data	RCVDATA	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Receive exit user name	RCVEXIT	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Security exit user data	SCYDATA	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Security exit name	SCYEXIT	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Send exit user data	SENDDATA	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Send exit name	SENDEXIT	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Sequence number wrap	SEQWRAP	Yes	Yes	Yes	Yes			Yes	Yes
Shared connections	SHARECNV					Yes	Yes
Short retry count	SHORTRTY	Yes	Yes					Yes	Yes
Short retry interval	SHORTTMR	Yes	Yes					Yes	Yes
Security policy protection	SPLPROT	Yes	Yes	Yes	Yes
SSL client authentication	SSLCAUTH		Yes	Yes	Yes		Yes		Yes	Yes
SSL cipher specification	SSLCIPH	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
SSL peer	SSLPEER	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Channel statistics	STATCHL	Yes	Yes	Yes	Yes			Yes	Yes
LU 6.2 transaction program name	TPNAME	Yes	Yes		Yes	Yes		Yes	Yes
Topic root	TPROOT									Yes
Transport type	TRPTYPE	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Use client ID	USECLTID									Yes
Use dead letter queue	USEDLQ	Yes	Yes	Yes	Yes			Yes	Yes
User ID	USERID	Yes	Yes		Yes	Yes		Yes
Transmission queue name	XMITQ	Yes	Yes
Notes: None of the administrative interfaces allow this attribute to be inquired or set for CLUSSDR channels. You will receive an `MQRCCF_WRONG_CHANNEL_TYPE` message. However, the attribute is present in CLUSSDR channel objects (including MQCD structures) and a CHAD exit can set it programmatically if required.

IBM MQ for some platforms might not implement all the attributes shown in this section. Exceptions and platform differences are mentioned in the individual attribute descriptions, where relevant.

The name of each attribute is shown in brackets.

The attributes are arranged in alphabetical order in groups.