Cisco 4006 Operating System

WOW you can buy a Catalyst 4006 chassis switch on ebay for £1 + £ Delivery.. Yep. I have two of them. 5 useable slots, 3 PSU's.. WOW..

Just be aware of one thing.

the 4006 and 4003 ( forerunner to the 4500 series )come in two flavours CATOS and IOS.

Most people have heard of IOS and that it's the Operating system that Cisco Switches and Routers run on. Well that's true to a degree, prior to the introduction of IOS and for a long time after it's introduction CISCO also ran CATOS.

Whilst CATOS can do most of the core functions of IOS, it is not as feature rich and the command set although simmilar is a bit awkward to get your head round at first if transposing between CATOS and IOS. The two do interoperate fairly well but obtaining support from Cisco is fruitless and online information is thin on the ground.

So if the unit has 1 of the following supervisors it's CAT OS and also only layer 2

WS-X4012 ( Super I )
WS-X4013 ( Super II )

If it has one of the follwoing or a later card then it should have IOS and Layer 3 Capability

WS-X4014 ( Super III )
WS-X4515 ( Super IV )


There is also an addon Layer 3 routing board for the 4012/4013 called the WS-X4232-L3that also incorporates 32 10/100 sockets.


The 4006 remains a good core switch for small operations where density of ports is a key factor. But don't rely on one for mission critical operation.

Rob