Port issue on 6509 being replaced by a 3750

[RonaldNutter]

I have a 6509 at a remote office that is being replaced by a pair of 3750's (6509 was overkill).  I have a port on the 6509 that is configured like this -

interface GigabitEthernet1/1

description Riverbed:Inpath 0_0  then to Firewall

ip address 10.1.1.1 255.255.255.0

I have never seen a port on a 6509 configured like this.  Havent been able to find out why it was set up this way.  The rest of the office is on another subnet i.e. 10.1.2.0 255.255.255.0.  I can only guess why the port was setup this way.  Unfortunately, I am working with a "managed" network, so the carrier handles the router at the office and I cant make any changes myself and have to go though a series of requests/explanations/etc with them to get any changes mande. It will be easiest to make the 3750 work in a similar manner.

I have tried to configure the 3750 to do the replacement port Gi1/0/1 exactly the same way and have been able to get it to take the ip address command.  Only thing I can figure out is to create another vlan on the switch, put the ip address for gi1/1 in that vlan interface and then put the port that will replace Gi1/1 on the 3750 into that new vlan.

I am not running any routing protocols on the 6509 and only see a static route pointing to a different address on the 10.1.1.0 subnet from the 6509 which I believe is the onsite firewall.  If there is another way around this, I would appreciate any suggestions.  A junior engineer will be going out instead of me, so I would like to have this as plug and play as possible.

Thanks,

Ron

[Dan-Ciprian Cicioiu · Accepted solution]

Hi,

On 6500 series all the ports are by default Layer 3 ports.

On 3750 series all the ports are by default Layer 2 ports.

So the solution for 3750 is :

interface fa1/0/1

description Riverbed:Inpath 0_0  then to Firewall

no switchport                                

ip add 10.1.1.1 255.255.255.0

"no switchport" , transforms the Layer 2 port into a Layer 3 port.

Dan

[RonaldNutter]

Dan:

Many thanks for that.  Wouldnt have thought about that.  Also appreciate the clarification on the differences between the two platforms.  I have my CCNP Security but this reinforces why I need to get my CCNP R/S.

Ron