Line User Host(s) Idle Location
* 6 vty 0 admin idle 00:00:00 10.32.20.1
7 vty 1 admin idle 00:00:22 10.32.20.7
Interface User Mode Idle Peer Address
Vi3 PPPoATM 00:00:00 18.104.22.168
This shows the open sessions to your router. The line with the * is the current session, where we used the command. If you want to kill an open Telnet session, use command clear line x
To see the active sessions from your remote device, use command show sessions
If you enter a sessionnumber you'll access it, use disconnect to leave.
Ctrl-Shift-6-x brings you back, it also suspends Telnet/SSH sessions.
Another useful command is show line which gives a nice overview.