Bandung, Telkom University - When CCNA or CCNP candidates configure their home labs, Cisco access servers are typically an afterthought. This router doesn't actually do anything in the production part of the lab, so it doesn't really matter.
However, if you have two or more devices in your home lab, you'll find that moving the console cable from one router to another frequently becomes very cumbersome. This is exactly what the Home Lab Access Server does. I can connect my PC to one of her devices while working in her home lab without constantly disconnecting and reconnecting the console cable. The console cable connects directly to the access server, which connects to all other equipment in the home lab. Once you start using one, you'll wonder how you managed without it.
The term "access server" is somewhat misleading. This isn't a server in the traditional sense, it's a Cisco router with an asynchronous serial port. These ports connect to other devices in your home lab. There are two affordable access server models for him, the Cisco 2509 and the Cisco 2511. These can be found on eBay and other vendors on the web. You will also need an octal cable. One end of the cable has a large connector that connects to the access server. The other end is actually eight separate cables, each with an RJ-45 connector. These ports are numbered 1 through 8 and connect to the console port of each router and switch. It is important to write down the number of each connector that connects to other experimental equipment.
Now that you've got the physical equipment, let's take a look at a typical configuration of an access server:
- no service password-encryption
- no service udp-small-servers
- no service tcp-small-servers
- no ip domain-lookup
- ip host r1 2001 10.4.4.4
- ip host r2 2002 10.4.4.4
- ip host r3 2003 10.4.4.4
- ip host sw1 2004 10.4.4.4
- ip host sw2 2005 10.4.4.4
- ip host FrameSwitch 2006 10.4.4.4
- interface Loopback555
- ip address 10.4.4.4 255.255.255.0
- line con 0
- exec-timeout 0 0
- logging synchronous\
- line 1 16
- no exec
- transport input all
You can assign any loopback address and number here the important thing to note is that the IP HOST table you will build constantly refers back to the loopback address on the access server.
In this configuration, I have the octal cable's connector 1 in R1, 2 in R2, 3 in R3, 4 in SW1, 5 in SW2, and 6 in my frame relay switch. The number "2001" in the first line of the IP HOST table refers to that connector. That's why it is important to note the number on a given connector you place in the console port of a router or switch.
The asynchonous lines are identified by "line 1 16". This access server has 16 possible connections many will just have 8, which is usually plenty. Regardless of how many lines you have, you'll need the commands transport input all and no exec to allow reverse telnet to work effectively.
There's one more thing to watch out for. When you first connect to the AS for a practice session, you will need to open the line to each device by using the full hostname of the device as shown in the IP HOST table. Here, you would begin by entering R1, R2, R3, SW1, SW2, and FrameSwitch to open the line to each device. After that, you need to enter the line number - 1, 2, 3, 4, 5, and 6. It sounds a little confusing at first, but after just a few minutes of practice you'll be doing it without even thinking about it.
When you are working in your home lab, you will not go from one device to another that is, when you are done on R1 and want to configure R2, you must go back to the access server and then to R2. The keystroke to do this is . Again, it may sound complicated, but after a little practice you will again do this without thinking about it.
Adding an access server to your CCNA or CCNP home lab may not be on your mind now, but once you add a few more routers or switches to the lab, you'll want to spend more time configuring and practicing and less time moving a cable around.
