TCPNAME start option


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   '-TCPNAME--=--tcp_job-name-'

TCPNAME specifies the job name of the TCP stack through which VTAM® communicates with the IP network. The value specified for tcp_job-name is the 1-8 character job name of the required TCP stack.

The TCP/IP stack must be at a level to support Enterprise Extender. However, if there are multiple TCP/IP stacks, you may need to specify one, as there are products which predefine the IP address of partner nodes, and these nodes require z/OS® CS to send through a given address, and, therefore, a given TCP/IP stack.

Note:

If neither the IPADDR nor the HOSTNAME operand are specified on any of the GROUP definition statements within the Enterprise Extender XCA major node, then either the HOSTNAME, TCPNAME or IPADDR start option must be specified in order to initiate an Enterprise Extender link. If VTAM has been activated without the specification of one of these options, then the MODIFY VTAMOPTS command can be used to set one of these options. In this case, if an Enterprise Extender link activation is attempted without HOSTNAME, TCPNAME or IPADDR specified, then the link activation will fail with the IST1890I message.
TCPNAME can be dynamically modified using MODIFY VTAMOPTS but the new value will not be used until all lines in the XCA major node used for Enterprise Extender are inactive. However, displays of VTAM start options will show the new value immediately. Any subsequent line activation from the Enterprise Extender XCA major node will make use of the new TCPNAME value.
The TCPNAME start option is required in a CINET environment if any of the following conditions exist:
- The IPADDR parameter is specified on any of the Enterprise Extender XCA major node GROUP definition statements.
- The HOSTNAME parameter is specified on any of the Enterprise Extender XCA major node GROUP definition statements.
- The HOSTNAME keyword is specified as a VTAM start option.
If OMVS is not initialized at Enterprise Extender line activation, a Common INET environment is assumed.

In this case, if an Enterprise Extender link activation is attempted without TCPNAME specified, link activation will fail with message IST1897I.
TCPNAME is meaningful only if the NODETYPE start option is also used.

Restriction: All local Enterprise Extender static VIPA addresses must be associated with a single TCP/IP stack. Even in Common-INET environments, EE always establishes affinity with one and only one TCP/IP stack.

Rules for EE line activation:

In a CINET environment, you must specify the TCP/IP stack name (using the TCPNAME start option) whenever host name resolution is to be performed during an EE line activation.
In a CINET environment, you must specify the TCP/IP stack name (using the TCPNAME start option) whenever the HOSTNAME or IPADDR value is specified on any GROUP statements in the EE XCA major node, even if no lines in the group have ever been activated.
In an INET or a CINET environment, you must specify the TCP/IP stack name (using the TCPNAME start option) when neither the HOSTNAME value nor the IPADDR value have been specified on any GROUP statements in the EE XCA major node, and neither the HOSTNAME start option nor the IPADDR start option have been specified.
If a HOSTNAME value or an IPADDR value is specified on any GROUP statements in the EE XCA major node, then a HOSTNAME value or an IPADDR value must be specified (or inherited from the HOSTNAME or IPADDR start option) on all GROUP statements for which EE lines will be activated.

Rule for learning a local static IPv4 VIPA address for EE from the TCP/IP stack:

VTAM dynamically obtains a local IPv4 VIPA address from the TCP/IP stack only when neither the HOSTNAME value nor the IPADDR value have been specified on any GROUP statements in the EE XCA major node, and neither the HOSTNAME start option nor the IPADDR start option have been specified. In this case, the TCP/IP stack name must be specified (using the TCPNAME start options). The TCP/IP stack is responsible for obtaining a local static IPv4 VIPA address for use by Enterprise Extender.

Rules for setting the HOSTNAME and IPADDR start options:

When an IPv4 address for EE has been obtained dynamically from the TCP/IP stack, neither the HOSTNAME nor the IPADDR start option can be set (using the MODIFY VTAMOPTS command) until the EE XCA major node is deactivated.
Resetting the HOSTNAME start option (using MODIFY VTAMOPTS,HOSTNAME=NONE) is allowed only when the EE XCA major node is inactive.
Resetting the IPADDR start option by using MODIFY VTAMOPTS,IPADDR=0.0.0.0, or by using an IPv6 IP address of all zeros, usually written as IPADDR=::, is allowed only when the EE XCA major node is inactive.
When the MODIFY VTAMOPTS command is used to set the HOSTNAME start option to any value other than NONE, the IPADDR start option is reset, because these start options are mutually exclusive. Message IST1895I will indicate the IPADDR start option has been reset
When the MODIFY VTAMOPTS command is used to set the IPADDR start option to any value other than 0.0.0.0 or an IPv6 IP address of all zeros, usually written as ::, the HOSTNAME start option is reset, because these start options are mutually exclusive. Message IST1895I will indicate the HOSTNAME start option has been reset.