If you connect directly to the Backup Server with isql and attempt to issue a command, you will get messages like the following:
1> dump database master to tapedump1 2> go
No language handler installed. Language cmd: dump database master to tapedump1
This is expected behavior because Backup Server is not a stand-alone Adaptive Server. It is an Open Server application, is not intended to accept direct commands, and, therefore, has no way of parsing them. All commands to the Backup Server, such as shutdown or dump and load, can be issued only from a running Adaptive Server.