TN3270: Limiting Users by Port Value (139675)

WORKAROUND

To implement checking on a given port range, the TN3270 server configuration file (TNSVRCFG.TNC) must be manually edited.

For example:

This sample TN3270 configuration file shows one TN3270 pool configured to allow any client Internet protocol address or client port number access to the LUA LUs in the pool.

   [SNA Resource 1]
   Name=TNTEST
   Sessions=16
   MaxSessions=16
   TerminalName1=IBM-3276-3
   TerminalName2=IBM-3278-3
   TerminalName3=IBM-3278-3-E
   TerminalName4=IBM-3279-3
   TerminalName5=IBM-3279-3-E

   [Group 1]
   Name=TNTEST
   Comment=
   SNAResource1=TNTEST
   IPConnection1=000.000.000.000,000.000.000.000,00000,65535

To modify the available port numbers change the last two numbers (00000,65535) to the desired range.

Example Two:

   [SNA Resource 1]
   Name=TNTEST
   Sessions=16
   MaxSessions=16
   TerminalName1=IBM-3276-3
   TerminalName2=IBM-3278-3
   TerminalName3=IBM-3278-3-E
   TerminalName4=IBM-3279-3
   TerminalName5=IBM-3279-3-E

   [Group 1]
   Name=TNTEST
   Comment=
   SNAResource1=TNTEST
   IPConnection1=000.000.000.000,000.000.000.000,50000,60000

This sets the allowable client port range to 50000-60000. Any client attempting to connect with a different local port number will be denied. If this occurs, the following TN3270 errors will occur:

On the client machine:

Warning 512
TN3270 Service Error 512
Access for IP address <client IP address> port <client port number>
is not configured.

On the server machine:

Warning 603
TN3270 session with client at <client IP address> <port <client port
number>> using LU <LU name> terminated abnormally because:

Access for IP address <client IP address> <port <client port number>> is
not configured.
Explanation: A TN3270 client session was terminated abnormally.

Action: No action is necessary.

TN3270: Limiting Users by Port Value (139675)

SUMMARY

WORKAROUND