For Application Server 8, the error codes for the start and stop subcommands of the asadmin command were based on the desired end state. For example, for asadmin start-domain, if the domain was already running, the exit code was 0 (success). If domain startup failed, the exit code was 1 (error).
For Enterprise Server, the exit codes are based on whether the commands execute as expected. For example, the asadmin start-domain command returns exit code 1 if the domain is already running or if domain startup fails. Similarly, asadmin stop-domain returns exit code 1 if the domain is already not running or cannot be stopped.