Sometimes there are times that you will need to grant access to other administrators to access the CISCO ASA using telnet.
In Cisco ASA Devices enabling Telnet will not allow all network\hosts to access the ASA using Telnet which will work with Routers and Switches.
In ASA we need to add hosts or networks to the Allowed telnet access list.
First, to view who can access the ASA using telnet type:
ASA# sh run telnet
telnet 10.60.4.20 255.255.255.255 inside
telnet 10.60.4.30 255.255.255.255 inside
In this case we have two host that can access the ASA using telnet.
To add an host to the Telnet access list type:
ASA (config)# telnet 10.60.4.30 255.255.255.255 inside
Hostname or A.B.C.D The IP address of the host and/or network authorized to
You can also use the ASDM GUI interface by going to:
Configuration > Device Managment > Management Access > Command Line (CLI) >Telnet