The DBMaint or archive_events process appears to have removed machine defintions it should not have.
This resulted in AutoSys not being able to run some jobs until the machine definitions were added back.
STARTJOBFAIL 02/23/2021 06:14:43 1 PD 02/23/2021 06:14:44
<Could not obtain a valid machine from the job definition machine attribute value.>
autorep -m does not show the machine
Release : 11.3.6
For now comment out archive_events entries in the %AUTOSYS%/bin/DBMaint.bat that archive machines to avoid the problem.
See: PROB #: 4879
Machines being deleted that should not.
This will be addressed in a future update / patch.