The Gen Transaction Enabler (aefuf/aefad) running on Unix (AIX) appears to have lost connection. In review of the aefuf log file, see the error message:
==>aefuf: Failed to connect to server. Response code 79
==>aefuf: Failed to connect to any server
What is a Response code 79?
The 'Response code 79' is a "ECONNREFUSED" (Connection refused) on Unix (AIX).
What has happened is that the aefuf has lost its connection to the aefad process, possibly because the aefad has stopped. The aefuf is trying to reconnect to the aefad and its getting the error noted in the aefuf logs.
In this situation it is best to stop any and all aefuf's connected to the affected aefad, make sure that the affected aefad is stopped and then restart all the processes again, ensuring that the aefad is started first.