You might want to run multiple TCP/IP stacks on the same system to provide network
isolation for one or more of your applications. For example, for multiple Open System Adapter (OSA)
features, you might want each one connecting your system to a different network. You can assign a
TCP/IP stack to each feature.
Before you begin
When configuring the product on a system with multiple stacks, you must first establish the
product's stack affinity to the desired stack. Establishing stack affinity binds all socket
communications to that stack, and allocates the proper host name resolution configuration data sets
to the product. These data sets enable host name lookups to have the desired results.Use the
NETWORK DOMAINNAME parameter of SYS1.PARMLIB(BPXPRMxx) to specify the common
INET physical file system, C_INET PFS, and then use this file system to set up multiple TCP/IP
stacks. This physical file system allows you to configure multiple physical file systems (network
sockets) and make them active concurrently.
If you plan to configure the product to use a
non-default TCP/IP stack, consult
z/OS®
UNIX System
Services Planning, and
z/OS Communications
Server: IP Configuration Reference, for details.
About this task
Avoid trouble: In the following steps, you set a number of variables.
Set these variables at the node level.
To
configure the product on a system with multiple stacks:
Procedure
- Configure the data set for each application server's host name resolution.
In
the administrative console, click .
- Add the RESOLVER_CONFIG UNIX process variable and specify the data set name in the
value field.
- Export the RESOLVER_CONFIG variable in client shell scripts.
- You can also use JCL to specify the name resolution configuration data set. To use JCL, add
//SYSTCPD DD DSN=some.tcpip.DATA,DISP=SHR to the server JCL. The RESOLVER_CONFIG variable overrides
the SYSTCPD DD statement.
See
z/OS Communications
Server: IP Configuration Reference, for more information on the RESOLVER_CONFIG
variable.
- Establish the Application Server's stack affinity to the
desired stack.
- In the administrative console, click and
set the _BPXK_SETIBMOPT_TRANSPORT UNIX process variable to the value
of the desired transport.
If this variable does not exist,
click New and add it.
- Export the _BPXK_SETIBMOPT_TRANSPORT variable in client
shell scripts.
To set the BPXK_SETIBMOPT_TRANSPORT variable in the
was.env file for the Daemon, you must prefix the variable with DAEMON_.
This additional information causes the transformer that generates the was.env
files to put add the variable to the was.env file for the Daemon. Because the
_BPXK_SETIBMOPT_TRANSPORT variable already has a leading underscore, the final
version of this variable, when set for the Daemon, contains of two underscores preceding the
variable name, as shown here DAEMON__BPXK_SETIBMOPT_TRANSPORT.
See z/OS UNIX System
Services Planning, for more information on the _BPXK_SETIBMOPT_TRANSPORT
variable.