Making a Cisco Rollover Cable

If you’ve been following my Tweets lately, your’re familiar with my home lab project.

To make connecting to all my devices a little easier, I picked up a Cisco 2511-RJ access server on eBay.  The nice thing about the 2511-RJ is that it provides you with an AUI Ethernet interface and 16 ASYNC ports.  These ASYNC ports are RJ45-based, which allows you to use standard rollover cables instead of messy octal (or octopus) cables.

When I received my 2511-RJ, I was a little disappointed that it didn’t come with even a few rollover cables. Was that a problem?  Not really.  With a standard engineer’s tool bag, you can be up and running in no time.

Step 1: Find a leftover Cisco console cable. If you’ve done any number of deployments you (like me) probably have 5-10 of these crammed in a bag somewhere.  Pull one of them out.  Depending on lab setup, you can make 2-3 rollover cables per console cable.

Step 2: Cut off the end with the DB-9 connector and strip the wire so that the eight color copper wires show.  Leave about 2 cm of exposed wire.  You’ll noticed that the end with the RJ45 plug on it has the wires in a particular order: Black to Purple.  When you go to add the plug on the other end (next step), make sure that set of wireless is in the opposite order (e.g. Purple to Black).

Step 3: Using your crimpers, add an RJ45 plug onto the other end of the cable.  Notice in the picture below how the order of the wires  are reversed (or “rolled-over”).

That’s it!