How to configure SSH access on Cisco IOS (switch or router):

1. Setting hostname and domain-name

switch# configure terminal
switch(config)#hostname catalyst
catalyst(config)#ip domain-name itmaranatha.org

2. Generate RSA keys (use 1024 bit for SSHv2 enabled)

catalyst(config)#crypto key generate rsa

3. Configure line vty

catalyst(config)#line vty 0 15
catalyst(config-line)#login local
catalyst(config-line)#transport input ssh

4. Create local user/pass

catalyst(config)#username [user] privilege 15 secret [password]

5. Fine tuning

catalyst(config)#line vty 0 15
catalyst(config-line)#exec-timeout 5
catalyst(config-line)#exit
catalyst(config)#ip ssh version 2

Source:
– https://www.pluralsight.com/blog/tutorials/configure-secure-shell-ssh-on-cisco-router