Logical CICS server definitions

LOGICALSERVER section definitions are deprecated and superseded by policy-based dynamic server selection definitions. This change was introduced with CICS® Transaction Gateway Version 8.1.

For information about server selection see Dynamic server selection.

A LOGICALSERVER section definition in the configuration file (ctg.ini), provides a mapping of a logical CICS server name to an actual CICS server name where work is to be sent. The logical CICS server name is an alias that can be passed to CICS Transaction Gateway on an ECI or ESI request. The function provided by LOGICALSERVER section definitions is incorporated into policy-based dynamic server selection and this new mechanism provides enhanced capability and flexibility for dynamic server selection.

Replace LOGICALSERVER section definitions with policy-based DSS definitions. For example the definitions:

SECTION LOGICALSERVER = PAYMONTH
Server = PAYROLLA
ENDSECTION
SECTION LOGICALSERVER = PAYWEEK
Server = PAYROLLB
ENDSECTION

can be replaced by the definitions:

SECTION GATEWAY
....
DSSPolicy = POLICY1
ENDSECTION
SECTION DSSPOLICY = POLICY1
SUBSECTION MAPPINGS
PAYMONTH=GROUP1
PAYWEEK=GROUP2
ENDSUBSECTION
SECTION DSSGROUP = GROUP1
Servers = PAYROLLA
Algorithm = Failover
ENDSECTION
SECTION DSSGROUP = GROUP2
Servers = PAYROLLB
Algorithm = Failover
ENDSECTION

When using LOGICALSERVER section definitions:

  • If a request does not specify the name of a CICS server, CICS Transaction Gateway uses the default CICS server, if one has been defined. The same applies when using policy-based DSS, if a request does not specify the name of a CICS server and no server group mapping is defined.
  • If a request does not specify a name and a default CICS server has not been defined, CICS Transaction Gateway assumes that the EXCI protocol is being used, and delegates the decision about which CICS server to use, to EXCI. The same applies when using policy-based DSS, if a request does not specify a name that matches any server group mapping and a default CICS server has not been defined.

For information about the LOGICALSERVER section of the configuration file see LOGICALSERVER section of the configuration file.