Resolving APPC or CPI-C application problems

If you are having problems with an APPC or CPI-C application, including a Java™CPI-C application, do the following:

  1. Check that the application is correctly installed.
  2. For a Java CPI-C application, check that the appropriate environment variables are set correctly, as follows.

    Before compiling and linking a Java CPI-C application, you need to specify the directory where Java classes are stored. To do this, set and export the environment variable CLASSPATH to /usr/lib/sna/java/cpic.jar/cpic.jar.

    Before running a Java CPI-C application, you need to specify the directory where libraries are stored, so that the application can find them at run time.

    To do this, set and export the environment variable as follows.

    For a 32-bit application:

    export LD_LIBRARY_PATH=/usr/lib/sna

    For a 64-bit application:

    export LD_LIBRARY_PATH=/usr/lib/sna

    export PATH=/usr/java5_64/jre/bin:/usr/java5_64/bin:$PATH

    You may also need to set and export the APPCTPN to specify the local TP name for the application, as described in IBM Communications Server for Data Center Deployment on AIX or Linux CPI-C Programmer's Guide.

  3. Check that the mode, LUs and link required are correctly configured.
  4. If a problem occurs when the application originates the conversation do the following:
    1. Check that the link is active (this may happen on demand). Refer to Check communication with other SNA nodes
    2. Check that the relevant session is started (this may happen on demand)
  5. If a problem occurs when the application receives an incoming conversation request, do the following:
    1. Check that the link is active (this may happen on demand if the link is configured as incoming)
    2. Check that the relevant session is started (this may happen on demand)
    3. If the receiving application is dynamically loaded (invokable), also check that the TP configuration information has been configured correctly (refer to the IBM Communications Server for Data Center Deployment on AIX Administration Guide for more information about configuring TP information).
  6. Verify that the session limit is sufficient for the number of applications required.
  7. Check that you are not mixing single-session and parallel-session modes on an LU-LU pair.
  8. The APPN architecture does not support independent LU 6.2 (parallel sessions) across a link station (typically SDLC) that is established without XID exchange (that is, with just SNRM and UA). Therefore, if the host does not send XIDs, independent LU 6.2 cannot be used.
  9. Check the correct allocate type (for example, an immediate allocate needs a contention winner session).
  10. For CPI-C applications, set the local LU name (using the snaadmin define_cpic_side_info command or APPCLLU environment variable) and TP name (APPCTPN), or use the default LU pool and TP name.