Configuring Secure Shell (SSH) 
Configuring the Switch for SSH Operation 
Notes  When you generate a host key pair on the switch, the switch places the key 
pair in flash memory (and not in the running-config file). Also, the switch 
maintains the key pair across reboots, including power cycles. You should 
consider this key pair to be “permanent”; that is, avoid re-generating the key 
pair without a compelling reason. Otherwise, you will have to re-introduce the 
switch’s public key on all management stations you have set up for SSH access 
to the switch using the earlier pair. 
Removing (zeroing) the switch’s public/private key pair renders the switch 
unable to engage in SSH operation and automatically disables IP SSH on the 
switch. (To verify whether SSH is enabled, execute show ip ssh.)However, any 
active SSH sessions will continue to run, unless explicitly terminated with the 
CLI 'kill' command. 
To Generate or Erase the Switch’s Public/Private RSA Host Key Pair.  
Because the host key pair is stored in flash instead of the running-config file, 
it is not necessary to use write memory to save the key pair. Erasing the key 
pair automatically disables SSH. 
Syntax:  crypto key generate ssh  [rsa] 
Generates a public/private key pair for the switch. If a 
switch key pair already exists, replaces it with a new 
key pair. (See the Note, above.) 
crypto key zeroize ssh [rsa] 
Erases the switch’s public/private key pair and dis-
ables SSH operation. 
show crypto host-public-key 
Displays switch’s public key. Displays the version 1 
and version 2 views of the key.
 [ babble ] 
Displays hashes of the switch’s public key in 
phonetic format. (See 
“Displaying the Public 
Key” on page 7-14.) 
[ fingerprint ] 
Displays fingerprints of the switch’s public key 
in hexadecimal format. (See “Displaying the 
Public Key” on page 
7-14.) 
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