Configuring the DSS Policy File

You can have CICS® Transaction Gateway separate web service calls from traditional ECI calls by configuring a Dynamic Server Selection (DSS) policy.

1. Enable the dynamic server selection policy.
   In the SECTION GATEWAY of the configuration file, enable dynamic server selection by specifying the name of the policy, e.g. POLICY1 :

   # Enable dynamic server selection policy
       DSSPOLICY=POLICY1

2. Define the DSS policy.
   In the configuration file define a SECTION DSSPOLICY with two mappings:

   • The first mapping is for web service requests that specify a server name of WEBCICS. These will be passed to the group of CICS servers called WEBGROUP that are to be defined in a later step.
   • The second mapping is for ECI requests. These will be passed to the group of CICS servers called ECIGROUP that are to be defined in a later step.

   For example:

   SECTION DSSPOLICY = POLICY1
      SUBSECTION MAPPINGS
         WEBCICS = WEBGROUP
         <ANY>= = ECIGROUP    
     ENDSUBSECTION 
   ENDSECTION

3. Define the web service.
   In the configuration file define a SECTION WEBSERVICE for the web service, For example myservice, which specifies a server name of WEBCICS:

   SECTION WEBSERVICE = myservice
      BindFile = bindfile.wsbind
      Server = WEBCICS
   ENDSECTION

4. Define the WEBGROUP for web service requests.
   In the configuration file define a SECTION DSSGROUP for the CICS servers receiving requests that came to CICS TG as web services. In this example, two CICS regions, CICSA and CICSB, are defined with an algorithm of RoundRobin to evenly spread the load.

   SECTION DSSGROUP = WEBGROUP
      Servers = CICSA,CICSB
      Algorithm = roundrobin
   ENDSECTION

5. Define the ECIGROUP for ECI requests.
   In the configuration file define a SECTION DSSGROUP for the CICS servers receiving requests that came to CICS TG as non-web services, such as ECI requests. In this example, two CICS regions, CICSX and CICSY, are defined with an algorithm of FailOver. This algorithm means that all requests will initially go to CICSX. If CICSX becomes unavailable, such as during a network outage, then all requests will be routed to CICSY instead.

   SECTION DSSGROUP = ECIGROUP
      Servers = CICSX,CICSY
      Algorithm = failover
   ENDSECTION

6. Define CICS server definitions.
   This example uses server definitions for the Gateway daemon to communicate with CICS over IPIC in remote mode. Each CICS server, CICSA, CICSB, CICSX, CICSY is similar to the example shown below for CICSn:

   SECTION IPICSERVER = CICSA
      DESCRIPTION=IPIC connection to CICSA
      HOSTNAME=cicssrvA.company.com
      PORT=12345
   ENDSECTION