Showing results for 
Search instead for 
Did you mean: 
Cisco Employee
Cisco Employee



There are a couple different variants of telnet/console hanging. This is mainly when using telnet to connect to a serial port over network. In some cases the XR telnet is hung, and other cases it is the internal Serial to XR Console session.  


There can be nested telnets:

Server                 Serial                XR Console                    XR telnet destination
                           <— internal telnet-->
    <—------------------ telnet to XR Console—————>
                                                <—— XR telnet to XR connected destination —>

Escape Sequence List

The following are the escape sequences for the various telnets:

1) XR telnet escape: ^^q = CTRL-SHIFT-6 followed by q
2) Serial to XR console escape: ^q  = CTRL-SHIFT-Q  (CTRL-q seems to work also)
3) Server telnet to Serial escape ^]   = CTRL-]


1) Kill the XR Telnet first if it exists.
- if you login to XR main console, if pressing keys cause garbage characters to appear, then you are probably still connected via the XR Telnet process


-if you can get to an XR aux port, you can see a telnet process running for the connection you made:

bash-4.3# ps -ef | grep telnet 

root 21303 20957 0 19:36 pts/2 00:00:02 telnet 0x1 -m 0x0 -p

^^q -> you may or may not get telnet prompt, this may exit immediately
ctrl+] -> exit Server to XR session
telnet back to Serial and go to (2)

2) Kill the Serial to XR Console 
- After killing the XR telnet process in (1), or if pressing [Enter] repeatedly shows nothing on the the screen

ctrl+Q -> upper case Q, though lower case seems to work sometimes

3) Kill Server to Serial Telnet

Telnet back for prompt.  Hit [Enter] multiple times

NOTE:  in some cases, even after you get XR Console back, double characters or garbage character appear.  Ctrl+], quit, [Enter] to exit Server to Serial Telnet, and then
telnet back

NOTE: sometimes the telnet prompt does not appear when hitting escape sequence.  Type quit, [Enter] anyway.

NOTE: The above can be used on Admin Console also

NOTE: Sometimes you need to exit the Server to XR Console session (^], quit) then telnet back in to clear the next level.
Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Quick Links