Enable SSH V2

This is a quick overview of how to see whether or not you are running ssh version 2 and activate it.

So we are going to start off with showing whether or not we are running SSH:

show ip ssh - shows us the current version and whether or not ssh is enabled or disabled

We can see a few things:

• SSH is disabled
• Version 1.5 is running
• We need to create RSA keys to be able to authenticate with SSH

Lets try to enable ssh by creating rsa keys:

crypto key generate rsa - 

Before the router will let us generate keys we must have a domain name. This can be your companies domain such as google.com or whatever domain you are using... for this case ill use cisco.com. 

Create domain name :

         ip domain name cisco.com

Then try to do key generate again :

        

        crypto key generate rsa 

After creating the domain and generating keys you should get the following:

It is asking us how many bits we are going to use 2048.

Now we see that SSH 1.5 has been enabled !

R3#sh ip ssh

SSH Enabled - version 1.5

Authentication timeout: 120 secs; Authentication retries: 3

R3#sh run | i ssh

ip ssh version 1

The current version running is version 1. Lets say we want to run version 2. We would enter the following:

!

R3(config)#ip ssh version 2

R3(config)#exit

!

R3#sh ip ssh

SSH Enabled - version 2.0

Authentication timeout: 120 secs; Authentication retries: 3