CCNA Lab dot Net

Some users of this free router pod has asked me several of questions on how I created this lab for everyone to use? I was
tasked to find a solution for network admin’s to work on our network without the network modifications impacting the admin’s connectivity. Naturally access to the console port would solve this problem. So I remembered back a few years in my Cisco class we talked about OOB or Out Of Band management. So I remember that there were a couple devices that I could configure to reverse telnet from a port to a device’s console port. I had a couple of CS500 (now EOL you might find them on ebay) hanging around from the 56K dial-up upgrade. You can also use an Async 16 or 32 A with octal cables to connect your devices. I
powered them on and began to configure for reverse telnet access.

Cisco 500 CS or NM-16A and a set of octal cables

First, I need to have access to the telnet on the CS500 so I configured networking and a gateway of last resort (or
default).

interface Ethernet 0

ip address 208.229.144.15 255.255.255.0

ip route 0.0.0.0 0.0.0.0 208.229.144.1

line vty 0 15

login

password cisco

Second, To telnet out these ports we need to specify an ip address and port number along with the telnet command. This
seems weird because we are not going to leave this access server. I need to configure a loopback address

interface Loopback 0

ip address 10.1.1.1 255.255.255.0

Third, we need a friendly way for anyone to connect to the lab routers; I would like to use IP hosts. Here I can define an
IP address and a line number. Per cisco we need to add 2000 + line number for the telnet command to work correctly

ip host SWITCH 2004 10.1.1.1

ip host ROUTER2 2003 10.1.1.1

ip host ROUTER1 2002 10.1.1.1

ip host LOCALHOST 10.1.1.1

Last, now here is the fun parts we need to tell each line how to handle certain types of flows. Now I configured each line
with the following commands.

line X

no exec (disables the EXEC process)

exec-timeout 0 0 (this will disconnect the user session once he disconnects from the access server, very useful because I
was
having a problem with open sessions after the user logs off the access server)

transport output telnet (we tell the port to only allow outbound telnet)

Wow that seems like a lot to ingest.

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