TCP/IP Connection Problems - ironstream_for_servicenow_discovery_1 - 7.5

For proper operation, the client component must be able to connect to the z/OS agent on both the message port and command port. After verifying that all required client component processes are running and all required agent subtasks are running on the z/OS system, perform these steps to verify TCP/IP communication between the server component and agent.

1. Check the status of the message port (default 6106) and command port (default 6107) on the Discovery Probe client by opening a command prompt and entering the commands:

   netstat -a | find "6106"

   netstat -a | find "6107"

   Each netstat command may take a few minutes to complete. If you see the port number with the word ESTABLISHED at the end, then the connection is up and running.

2. Check the TCP port status on the z/OS agent with this TSO NETSTAT command:

   NETSTAT CONN (PORT 6106 6107

   If communication is working properly, then the state should have "Establsh". Below is an example of a NETSTAT CONN output from a normal state:

   EZZ2587I VP390 0017D2FA 192.168.1.117..6106 192.168.1.174..41245 Establsh

   EZZ2587I VP390 0017D2FC 192.168.1.117..6107 192.168.1.174..41248 Establsh

3. Check the ev390mcs logs on the Discovery Probe for an indication of a problem. Look for connection messages in the log.
   1. In the connection message if you see a connection failure message with a result of "Connection Refused", then the TCP stack on the Proxy Server is getting a result back that indicates the mainframe port is not in a "Listen" state.
   2. If the mainframe ports are in "Listen" state and are still seeing a "Connection Refused", then check to see if there is a firewall in place between the Proxy Server and the z/OS system, and if so, make sure it has rules to allow bi-directional communication between the Discovery Probe and z/OS system.
   3. If you are seeing a connection failure with the result of "Connection timed out", this indicates a network routing error between the Proxy Server and the z/OS system.
4. If you see that the server component makes a successful connection, but the connection is closed 30 seconds later then reconnects immediately, this indicates a port conflict. In this case, change the default ports of 6106 and 6107 to a different range, for example, 6116 and 6117. 

   Note the change must be made on:

   1. The MSG_PORT and CMD_PORT parameters in the configuration file for the z/OS node.
   2. The "TCP" parameter card in the mainframe SYSIN parameters.