Disable Telnet on Cisco Switch and Router

 1.    You must disable Telnet on your Cisco switch/router since it will be enabled by default and will not disable until you manually disable it.

2.    RTR-01>enable

3.    RTR-01#conf t

4.    RTR-01 (config) #line vty 0 15

5.    RTR-01 (config-line) #transport input ssh
    a.    This transport command is telling the switch/router to only accept SSH connections

6.    RTR-01 (config-line) #end

7.    RTR-01#write

Change SSH Version

1.    When you enable SSH, it might default to a version number that you are not running or do not wish to run. Make sure to enable the correct version.

2.    First, you can find out which version you are running by doing the following:
    a.    RTR-01>enable
    b.    RTR-01#show run | include ssh version
        i.    Here it will show you which version of SSH you are running
        ii.    You can also just type RTR-01#show ip ssh

3.    Next, you can change your version of SSH
    a.    RTR-01>enable
    b.    RTR-01#conf t
    c.    RTR-01 (config) #ip ssh version YOUR_DESIRED_VERSION
    d.    RTR-01 (config) #end
    e.    RTR-01#write
        i.    Or copy-running-config startup-config

4.    Now, verify your version number:
    a.    RTR-01#show ip ssh
    b.    Orr you can type: RTR-01#show run | include ssh version

Create User and Password for Cisco Device

1.    First, you will need to determine if you want a normal user, or an admin user. The following is for a normal user:
    a.    >enable
    b.    #conf t (configure terminal)
    c.    (config) #username YOUR_USER_NAME secret USER_PASSWORD

2.    If you wish to create an admin user, the following can be done”
    a.    >enable
    b.    #conf t
    c.    (config) #username YOUR_USER_NAME privilege 15 secret USER_PASSWORD

3.    Finally, you will need to enable logins into the switch/router by doing the following:
    a.    >enable
    b.    #conf t
    c.    (config) #enable secret DESIRED_PASSWORD_HERE
        i.    This will start requiring you to utilize logins into the switch and also with a default password
        into the switch too.

4.    You have now created a basic lockdown on your Cisco device. Again, this is just super basic utilizing the Cisco built in login local database.

5.    Which you can enable (if you have not already) this way:
    a.    For the console line:
    b.    >enable
    c.    #conf t
    d.    (config) #int line con 0
    e.    (config-line) #login local
    
    f.    And finally for your VTY lines:
    g.    >enable
    h.    #conf t
    i.    (config) #line vty 0 15
    j.    (config-line) #login local

6.    The main thing you need here is the login local command. This tells the switch/router to use the local user database to login.