TCP stanza of the client configuration file

Use the TCP stanza to specify TCP network protocol configuration parameters.

Note: The description of each attribute of this stanza indicates which IBM® MQ clients can read that attribute. For a summary table for all IBM MQ MQI client configuration file stanzas, see Which IBM MQ attributes can be read by each client.

The following attributes can be included in the TCP stanza:

ClntRcvBuffSize = number|0
The size in bytes of the TCP/IP receive buffer used by the client end of a client-connection server-connection channel.

This attribute can be read by C, unmanaged .NET, IBM MQ classes for Java, IBM MQ classes for JMS, managed .NET, and managed XMS .NET clients.

A value of zero indicates that the operating system will manage the buffer sizes, as opposed to the buffer sizes being fixed by IBM MQ. If the value is set as zero, the operating system defaults are used. If no value is set, then the IBM MQ default, 32768, is used.

ClntSndBuffSize = number|0
The size in bytes of the TCP/IP send buffer used by the client end of a client-connection server-connection channel.

This attribute can be read by C, unmanaged .NET, IBM MQ classes for Java, IBM MQ classes for JMS, managed .NET, and managed XMS .NET clients.

A value of zero indicates that the operating system will manage the buffer sizes, as opposed to the buffer sizes being fixed by IBM MQ. If the value is set as zero, the operating system defaults are used. If no value is set, then the IBM MQ default, 32768, is used.

Connect_Timeout = number
The number of seconds before an attempt to connect the socket times out. The default value of zero specifies that there is no connect timeout.

This attribute can be read by C, unmanaged .NET, IBM MQ classes for Java, and IBM MQ classes for JMS clients.

IBM MQ channel processes connect over nonblocking sockets. Therefore, if the other end of the socket is not ready, connect() returns immediately with EINPROGRESS or EWOULDBLOCK. Following this, connect will be attempted again, up to a total of 20 such attempts, when a communications error is reported.

If Connect_Timeout is set to a non-zero value, IBM MQ waits for the stipulated period over select() call for the socket to get ready. This increases the chances of success of a subsequent connect() call. This option might be beneficial in situations where connects would require some waiting period, due to high load on the network.

There is no relationship between the Connect_Timeout, ClntSndBuffSize, and ClntRcvBuffSize parameters.

IPAddressVersion = MQIPADDR_IPV4|MQIPADDR_IPV6
Specifies which IP protocol to use for a channel connection.

This attribute can be read by C, unmanaged .NET, managed .NET, and managed XMS .NET clients.

It has the possible string values of MQIPADDR_IPV4 or MQIPADDR_IPV6. These values have the same meanings as IPV4 and IPV6 in ALTER QMGR IPADDRV.

KeepAlive = YES|NO
Switch the KeepAlive function on or off. KeepAlive=YES causes TCP/IP to check periodically that the other end of the connection is still available. If it is not, the channel is closed.

This attribute can be read by C, unmanaged .NET, IBM MQ classes for Java, IBM MQ classes for JMS, managed .NET, and managed XMS .NET clients.

[Windows]Library1 = DLLName|WSOCK32
[Windows]( Windows only) The name of the TCP/IP sockets DLL.

This attribute can be read by C and unmanaged .NET clients.