This tells us that your server is listening on port 80.
The bad request is because you typed "GET/" instead of "GET /".
This isn't really a telnet service. We are using telnet to check
the web service.
You can fix this by changing ForceHostP to 0 or false (in
/web/${server}/parameters/${server}.tcl) as Jonathan mentioned or by
setting hostname to 192.168.100.2