Just came across something I’d not noticed before in IOS. Apparently this has been around since IOS 10… There’s a command called “service linenumber” – it prints the line number and name of the device you are telnetting to, which can help in avoiding confusion.
Here’s a capture of what I did in my lab – telnet to R4 from R5, enter the command in global config, and telnet back in again to see the difference (note the name and line-number just after the second “open”):
Rack1R5#telnet 18.104.22.168 Trying 22.214.171.124 ... Open User Access Verification Password: Rack1R4>enable Password: Rack1R4#conf t Enter configuration commands, one per line. End with CNTL/Z. Rack1R4(config)#service linenumber Rack1R4(config)#exit Rack1R4#exit [Connection to 126.96.36.199 closed by foreign host]
Now, telnet back again – this time note the annoucement of the router name and line number after the session opens:
Rack1R5#telnet 188.8.131.52Trying 184.108.40.206 ... Open Rack1R4 line 322 User Access Verification Password: