SSH configure on Cisco router

SSH configure on Cisco router:

There are two versions of Secure Shell: SSH1 and SSH2. CiscoIOS 12.1(3)T was the first version to support SSH1; however, it does require the Data Encryption Standard (DES) or triple DES (3DES) IPSec encryption version of the IOS.

Step 1:

Router>enable

Router#configure terminal

Router(config)#hostname ssh                         >> hostname “ssh”. Its depend on you

ssh(config)#enable password 12345              >> (Optional) configure the privilege password

ssh(config)#ip domain-name cisco.com          >> Create domain as your policy   

ssh(config)#username admin password cisco  >> also use “secret” instead of “password”

ssh(config)#ip ssh version 2                           >> For version 2, default version 1

ssh(config)#crypto key generate rsa               >> Generate RSA encryption key (Note: ssh#crypto key zeroize rsa   >> to remove rsa key if needed)

........................................... Router Message......................................

The name for the keys will be: ssh.cisco.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         >> input bits as your requirement

% Generating 512 bit RSA keys, keys will be non-exportable...[OK]

.............................................................................................................

Step 2: Configure line vty

ssh(config)#line vty 0 4

ssh(config-line)#transport input ssh

ssh(config-line)#login local    >> For local Username Password database....

optional:

ssh(config)#ip ssh time-out 20   >> how many minute wait

ssh(config)#ip ssh authentication-retries 2

Step 3: SSH to router from PC

PC>ssh -l admin 1.1.1.1

Open

Password:                        >> enter admin password

ssh>enable

Password:                     >> enter privilege password

ssh#                              >> finally you login

 

Show ssh status:

ssh#show ip ssh

ssh#debug ip ssh 


Example to SSH configure: 
 
ssh#show running-config
Building configuration...
Current configuration : 920 bytes
!
version 12.4
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname ssh
!
enable password 12345
!
username admin password 0 cisco
!
ip ssh version 2
ip ssh authentication-retries 2
ip ssh time-out 20
ip domain-name cisco.com
!
interface Loopback0
 ip address 1.1.1.1 255.255.255.255
!
interface FastEthernet0/0
 ip address 192.168.140.1 255.255.255.0
 duplex auto
 speed auto
!
interface FastEthernet0/1
 ip address 10.10.10.1 255.255.255.0
 duplex auto
 speed auto
!
router eigrp 1
 network 192.168.140.0
 network 10.10.10.0 0.0.0.255
 network 1.1.1.1 0.0.0.0
 no auto-summary
!
ip classless
!
line con 0
line vty 0 4
 login local
 transport input ssh
!
end