Adjacent SSCP lists for CDRSCs

To define an adjacent SSCP list for a CDRSC, include the ADJLIST operand on the CDRSC definition statement. You can also code the ADJLIST operand on the GROUP definition statement, and the ADJLIST operand sifts down to any CDRSCs in the group for which ADJLIST is not coded. The ADJLIST operand specifies the name of a list of adjacent SSCPs, defined in an adjacent SSCP table using the ADJLIST definition statement followed by any number of ADJCDRM definition statements to identify the specific adjacent SSCPs in the list.

For example, the following sample adjacent SSCP list could be used by A02M to locate LU1 shown in Figure 1.

A02ADJ    VBUILD TYPE=ADJSSCP
** ADJACENT SSCP LIST: THIS LIST IS USED WHEN THE ADJLIST OPERAND
**                     FOR A CDRSC SPECIFIES LIST1
**
LIST1    ADJLIST
A01M     ADJCDRM

See the following sample CDRSC definition statement for LU1.

          VBUILD TYPE=CDRSC
LU1      CDRSC ADJLIST=LIST1

When an adjacent SSCP list is identified for a CDRSC, session setup requests are sent to only the SSCPs in the list. The values coded for SORDER and SSCPORD do not affect the search sequence. If the target resource is not owned by (or found through) one of the SSCPs in the list, session establishment fails. This enables strict control over adjacent SSCP selection.

When using adjacent SSCP lists for CDRSCs, the SSCP selection function of the session management exit routine can be used to delete or reorder entries in a list. VTAM® cannot dynamically add entries to an adjacent SSCP list.

To add, delete, or change an adjacent SSCP list for a CDRSC, use the MODIFY RESOURCE command. Adjacent SSCP lists for a CDRSC are displayed using the DISPLAY ADJSSCPS command. See z/OS Communications Server: SNA Operation for details on these commands.