How can I verify the health of a z/OS Enterprise Extender (EE) connection?

(1) Starting with zOS Communications Server V1R12, VTAM® by default sends a Logical Data Link Control (LDLC) probe to the remote partner to determine whether all ports are accessible during the activation of the EE connection. EE health verification for this connection activation fails if VTAM does not receive a response, or receives an error response, from the remote partner.

(2) VTAM also verifies the health of EE connections at other user-specified time intervals. To do this, VTAM sends an LDLC probe to the remote partner on a user-specified interval.

(3) The D NET,EE,LIST=EEVERIFY command displays all lines that failed EE health verification during the most recent LDLC probe.

(4) The D NET,EE,ID=puname or D NET,EE,ID=linename command displays EE health verification information of the most recent LDLC probe for a particular connection.

(5) VTAM provides the EE health verification information of the most recent LDLC probe to the NMI application upon its request. It includes success and failure information for all ports and contains the round-trip time information.

(6) VTAM issues this health verification failure message if health verification fails during the activation of an EE connection when it sends the LDLC probe to its remote partner:

   **IST2330I EE HEALTH VERIFICATION FAILED FOR puname AT time**

(7) During the activation of the EE connection, VTAM sends Logical Data Link Control (LDLC) probes to the remote partner to determine whether all five ports are accessible. If VTAM does not receive a response to any of the LDLC probe requests. VTAM continues with the activation of the EE connection between this node and the remote partner. If VTAM receives no replies to its LDLC probe requests, VTAM makes the determination that the remote partner does not support EE health verification and VTAM issues the following message:

   **IST2342I EE HEALTH VERIFICATION NOT SUPPORTED BY puname**

(8) When the EE Health verification fails on active connections, VTAM issues the following eventual action message:

    **IST2323E EE HEALTH VERIFICATION FAILED FOR ONE OR MORE CONNECTIONS**

This message remains on the console until a subsequent LDLC probe to the remote partner is successful or is erased by the operator.

When you see the above message, you can issue the D NET,EE,LIST=EEVERIFY command to display each line, which failed health verification on the most recent LDLC probe to its remote partner. The command displays the following message for each line with the line name, pu name, date and time:

     **IST2325I LINE linename PU puname ON date AT time**