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Recovery and Restart Procedures › MUF ABEND

MUF ABEND

When the MUF abends but CICS regions do not abend, CA Datacom CICS Services detects the abend and performs the following:

CA Datacom CICS Services Action

  1. The CA Datacom/DB interface sends a CA Datacom/DB return code 86 to the request once it detects that the MUF has abended.
  2. CA Datacom CICS Services closes all open User Requirements Tables (URTs) and marks them for reopening. CA Datacom CICS Services is typically restarted automatically when end users run reconnection transactions. If CICS transactions continue flowing to CA Datacom/DB, no action is required by anyone. Transactions continuing to flow automatically causes reconnections to MUF. If no work is flowing, no automatic processing is possible. Work generated in the CICS region or a manual connection using DBEC I,MUF(??) again makes automatic processing possible.
  3. CA Datacom CICS Services frees all the resources.
  4. After CA Datacom CICS Services has freed all resources for any CA Datacom/DB request from the application program, CA Datacom CICS Services attempts to reconnect to the MUF. If the reconnect fails, CA Datacom CICS Services passes return code 36 back to the application program.

User Action

Follow this procedure to return all URTs to their original status, that is, the status they had before the MUF abend.

  1. Do not issue DBOC OPEN/CLOSE commands or use DBEC to perform any OPEN/CLOSE after return code 86 is issued until you see the message DC00187I in the CICS JES job log for z/OS or the console log for VSE. If an OPEN/CLOSE is issued, the process to restore the originally opened status of the URTs cannot be accomplished automatically by CA Datacom CICS Services (to restore the URT environment manually, you have to issue the DBOC OPEN or RESTART command after the MUF has been enabled).
  2. After the MUF has been enabled, CA Datacom CICS Services can be restarted. This restart of CA Datacom CICS Services is usually restarted automatically by the end users running transactions that drive this work of reconnection. Typically, there is no action needed as long as CICS transactions are still flowing to CA DATACOM DB. This drives the connection back to MUF automatically. If no work is flowing, then no automatic processing is possible until work is generated in the CICS region or a manual connection is made using the DBEC I,MUF(??) connection.

System Action

The first CA Datacom/DB request following the MUF start up establishes communication between the MUF and CA Datacom CICS Services. Upon first request from a CICS application program, CA Datacom CICS Services automatically allocates needed resources and reopens all the URTs which were open when the MUF abended. No operator action is required to handle a URT that was open when the MUF abended.