How do you verify that SSH (Secure Shell) is operational on a Cisco switch?

show ip ssh shows the SSH version and settings; show ssh lists the active SSH sessions.

Verify SSH version and settings:

S1# show ip ssh
SSH Enabled - version 2.0
Authentication timeout: 120 secs; Authentication retries: 3

View active SSH sessions:

S1# show ssh
Connection  Version  Mode  Encryption  Hmac       State           Username
0           2.0      IN    aes256-cbc  hmac-sha1  Session started admin
0           2.0      OUT   aes256-cbc  hmac-sha1  Session started admin

Testing SSH from a PC:

• Use an SSH client (e.g., PuTTY) to connect to the switch SVI (Switch Virtual Interface) IP (Internet Protocol) address
• You'll be prompted for username and password
• After authentication, you get CLI (Command-Line Interface) access (S1> user EXEC mode)
• Type enable and enter the enable secret to reach S1# privileged EXEC mode

Go deeper:

• Secure Shell (Wikipedia) — the version, encryption and HMAC fields show ssh reports per session.