Cisco 4506

[osi-cisco]

I just recently took over a Network with a Cat 4506. Unfortunetly who ever built this network is using it as a layer 2 switch only. There isn't even an IP Address associated to it.  How do I turn up the routing feature and start using this switch with VLAN etc..?

[Reza Sharifi]

Hi Randy,

It all depends on how the network is set up and what you are trying to achieve.  If the 4506 is an access layer switch, then it can very well be a layer-2 switch and don't need to turn on layer-3.  But even in a layer-2 mode you should have a management IP address on the device so you can telnet/manage it remotely.

HTH

Reza

[Jon Marshall]

Randy

As Reza said, be careful before you enable ip routing. If there are multiple vlans in your network and they are communicating with each other then some other device must be doing the inter-vlan routing and so there is a good chance the 4500 is meant to be L2. It may have been purchased for port density/dual power supplies etc rather than it's L3 functions.

If there is a trunk from the 4506 to another switch start looking at that switch first to see if it is doing L3 switching.

Mangement is fairly easy but again you need to know what the management vlan for the switches is as it might not be vlan 1. Then you need to work out which switch is routing for this vlan and what the IP address for that vlan is on the L3 switch. When you have done that you then need to find a spare IP address in that vlan and allocate it to the 4500 switch eg.

int vlan

ip address x.x.x.x    <----- where x.x.x.x is a spare IP

ip default-gateway y.y.y.y   <--- where y.y.y.y is the IP address assigned to the management vlan interface on the L3 switch that is routing the management vlan

This will mean you can connect to the 4500 but it will still be L2. If you find that you need/want to make it L3 then come back with some more details and someone will be able to help you out.

Jon