Running multiple TCP/IP stacks on the same system

By assigning a TCP/IP stack to an integration node, you can run multiple TCP/IP stacks on the same system to provide network isolation for one or more integration nodes.

Before you begin

Use the NETWORK DOMAINNAME parameter of SYS1.PARMLIB (BPXPRMxx) to specify the common INET physical file system, C_INET PFS. You can then use the file system to set up multiple TCP/IP stacks. The physical file system enables you to configure multiple physical file systems, or network sockets, and make them active concurrently.

About this task

You must establish the stack affinity between the integration node and the TCP/IP stack. Establishing stack affinity binds all socket communications to the stack and allocates correct host name resolution configuration data sets to IBM® Integration Bus. The data sets enable host name lookups to be resolved correctly.

Procedure

Establish the stack affinity of the integration node to the required TCP/IP stack.
1. Set the following option in the component profile. The component profile is BIPBPROF for an integration node:
```
export _BPXK_SETIBMOPT_TRANSPORT=TCPIP_name
```
2. Submit BIPGEN to recreate the integration node ENVFILE.
3. Restart the integration node for the updates to take effect.
Optional: You can configure the data set for the host name resolution of each integration node.
1. Set the RESOLVER_CONFIG variable in the component profile. The component profile is BIPBPROF for an integration node. The RESOLVER_CONFIG variable can specify an appropriate MVS™ data set or a z/OS® UNIX file, for example, /etc/resolv.conf
```
export RESOLVER_CONFIG=example.TCPIP.DATA
```
  or
```
export RESOLVER_CONFIG=/example/USS/File
```
2. Submit BIPGEN to re-create the integration node ENVFILE.
3. Restart the integration node to enable the change to take effect.
For more information about the RESOLVER_CONFIG option, see the z/OS Communications Server IP Configuration Reference in the z/OS product documentation.