supervisorctl
horizon                          RUNNING   pid 21, uptime X days
postgresql                       RUNNING   pid 19, uptime X days
stellar-core                     STOPPED   X date

supervisor> start stellar-core
stellar-core: ERROR (spawn error)

stellar-core                     FATAL     Exited too quickly (process log may have details)
supervisor> restart stellar-core
stellar-core: ERROR (not running)
stellar-core: ERROR (spawn error)