Telnet and SSH Access to the ASA
We have already connected to the ASA through the console cable and through the ASDM. You can also configure Telnet and SSH access to the ASA to perform command-line configuration.
Telnet is a protocol used for connecting to line-based applications. Telnet traffic is sent in clear text, so you never want to use Telnet outside of a private network. SSH is always a better option, and Telnet should be used only when SSH is unavailable.
You can enable Telnet to the ASA through any interface. The only caveat is that Telnet to the outside interface must be protected by IPsec.
To configure Telnet, navigate to Device Management > Management Access > Command Line (CLI) > Telnet.
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