Customizing the TCP/IP data sets or files

To use TCP/IP, you must customize your TCP/IP data sets or files.

To customize your TCP/IP data sets or files, complete the following steps:

1. Find the high level qualifier (hlq) value in the resolve/tcpip.data file that z/OS® UNIX applications use in their TCP/IP stacks.
   This data set defines the high level qualifier, which is added to the beginning of other data set names used by TCP⁄IP.
2. Find the hlq.TCPPARMS(PROFILE) data set.
   This data set contains the PORT statement used to make DRDA and resync port reservations. The following example shows a sample hlq.TCPPARMS(PROFILE) entry for SYSTEM2:

   PORT  446  TCP  DB2CDIST          ; DRDA SQL port for DB2C
   PORT 5020  TCP  DB2CDIST          ; Resync port for DB2C
   
   PORT 5021  TCP  DB2DDIST          ; DRDA SQL port for DB2D
   PORT 5022  TCP  DB2DDIST          ; Resync port for DB2D

   This example assumes that DB2CDIST and DB2DDIST are the Db2 started procedure names.
3. Define the TCP/IP hostnames that Db2 needs to know.
   The local host name must be defined before DDF is started. All domain names referenced in the table SYSIBM.IPNAMES must be defined. You define the hostnames by configuring the hlq.HOSTS.LOCAL data set, the /etc/hosts file in the hierarchical file system (HFS), or the domain name server (DNS).

   After the hlq.HOSTS.LOCAL data set is configured, you have to execute the utility MAKESITE. This utility generates the hlq.HOSTS ADDRINFO and the hlq.HOSTS.SITEINFO data sets that are used to translate between domain names and IP addresses. MAKESITE generates under the userid that issued the MAKESITE. Therefore, those files have to be moved to the high level qualifier that represents TCP⁄IP. The hostname for the local Db2 subsystem must be defined in at least one of these places.

   You can also run the MAKESITE command with the HLQ parameter. You can set the HLQ parameter to the high level qualifier of the stack that you obtained in step 1. If you use the HLQ parameter, the hlq.HOSTS ADDRINFO and the hlq.HOSTS.SITEINFO data sets are created and updated under the correct high level qualifier, so you do not have to move the data sets from under the userid high level qualifier to the TCP⁄IP high level qualifier.

   If domain names are present in the CDB (in field IPADDR of table SYSIBM.IPNAMES), they must be defined in the z/OS data sets, the HFS or the DNS.

   Recommendation: To support a Parallel Sysplex® environment, use Dynamic Virtual IP Addresses (VIPA). To configure a Db2 subsystem to perform Dynamic VIPA routing, specify the Db2 group Dynamic VIPA on the TCP/IP PORT statement for the DRDA PORT number. This Dynamic VIPA must be the same for all Db2 members in the data sharing group. All clients must use the Dynamic VIPA to route requests to the Db2 group. To Db2 member-specific Dynamic VIPA is specified on the TCP/IP RESYNC PORT number in the TCP/IP profile data set for each Db2 member of the sysplex.

   The following example shows a sample hlq.TCPPARMS(PROFILE) entry for SYSTEM2:

   PORT 446  TCP  DB2DIST  BIND  db2_sysplex_VIPA        ;DRDA SQL port for DB2
   PORT 5001 TCP  DB2DIST  BIND  member_specific_VIPA    ;RESYNC port for DB2

4. Define the TCP⁄IP service names that Db2 needs to know.
   Configure the hlq.ETC.SERVICES data set or the /etc/services file in the HFS. If service names are present in the CDB (in field PORT of table SYSIBM.LOCATIONS), they must be defined in the z/OS data set or the HFS.

   The following example shows a sample hlq.ETC.SERVICES entry:

   DRDA        446/tcp             ; DRDA databases