Router>en
Router#config t
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#hostname jinyan
jinyan(config)#ip domain-name jinyan.com
jinyan(config)#crypto key ge
jinyan(config)#crypto key generate rsa
The name for the keys will be: jinyan.jinyan.com
Choose the size of the key modulus in the range of 360 to 2048 for
your
General Purpose Keys. Choosing a key modulus greater than 512 may
take
a few minutes.
How many bits in the modulus [512]: 512
% Generating 512 bit RSA keys, keys will be non-exportable...[OK]
jinyan(config)#ip ssh time-out 60
*?? 1 0:1:7.740: RSA key size needs to be at least 768 bits for ssh
version 2
*?? 1 0:1:7.740: %SSH-5-ENABLED: SSH 1.5 has been enabled
jinyan(config)#ip ssh au
jinyan(config)#ip ssh authentication-retries 2
jinyan(config)#line vty 0 15
jinyan(config-line)#transport input ssh
jinyan(config-line)#