Configuring CICS® Transaction Gateway for high availability requires the creation of various JCL files and configuration files.
The common configuration file is installed in the HFS under the directory <install_path>/samples/scenarios/sc03. The sample environment files are available in the partitioned data set (PDS) install_HLQ.SCTGSAMP.
Create a CICS Transaction Gateway configuration file GroupA_GW.ini using the values suggested in the table Table 1:
SECTION PRODUCT
APPLIDQUALIFIER=GROUPA # Common group APPLID qualifier
# APPLID is overridden by CTGSTART_OPTS
ENDSECTION
SECTION GATEWAY
maxconnect=500
maxworker=250
noinput=on
xasupport=on
# Enable dynamic server selection policy
DSSPOLICY=POLICY1
# Define tcp protocol handler, port 4148
protocol@tcp.handler=com.ibm.ctg.server.TCPHandler
protocol@tcp.parameters=connecttimeout=2000;
idletimeout=0;\
pingfrequency=10000;
port=4148;
bind=;
solinger=0;
# Define stats protocol handler
# Note: This port number is overridden by CTGSTART_OPTS
protocol@statsapi.handler=com.ibm.ctg.server.RestrictedTCPHandler
protocol@statsapi.parameters=port=;
bind=;
connecttimeout=2000;
maxconn=5;
ENDSECTION
SECTION IPICSERVER = CICSA1
DESCRIPTION=IPIC connection to CICSA1
HOSTNAME=server.ibm.com
PORT=4149
CONNECTTIMEOUT=5
SENDSESSIONS=250
ENDSECTION
SECTION IPICSERVER = CICSA2
DESCRIPTION=IPIC connection to CICSA2
HOSTNAME=server.ibm.com
PORT=4150
CONNECTTIMEOUT=5
SENDSESSIONS=250
ENDSECTION
CONNECTTIMEOUT applies when the target machine
is not reachable. For example, if the target LPAR is down or TCP/IP
on the target LPAR has been shut down.You must define a dynamic server selection policy and associated dynamic server selection group which will be used to determine which CICS server requests are sent to.
Edit the GroupA_GW.ini file and add a DSSPOLICY and DSSGROUP section.
Set Servers to the name of the CICS servers to contact. Set Algorithm to the algorithm to be used for choosing a CICS server.
For example:
# Define dynamic server selection policy
SECTION DSSPOLICY = POLICY1
SUBSECTION MAPPINGS
<NONE>=GROUP1
ENDSUBSECTION
ENDSECTION
# Define dynamic server selection group
SECTION DSSGROUP = GROUP1
Servers=CICSA1,CICSA2
Algorithm=ROUNDROBIN
ENDSECTION
CICSCLI=<config_path>/GroupA_GW.ini
CTGSTART_OPTS=-applid=CTGA1 -statsport=4151
PATH=/bin:/usr/sbin:<java_path>/bin
CTG_EXCI_INIT=NO
_BPX_SHAREAS=YES
CICSCLI=<config_path>/GroupA_GW.ini
CTGSTART_OPTS=-applid=CTGA2 -statsport=4152
PATH=/bin:/usr/sbin:<java_path>/bin
CTG_EXCI_INIT=NO
_BPX_SHAREAS=YES