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4003 CatOs vs 3750 IOS


We are in the process of replacing old catalyst 4003 (CatOs) switches with the new catalyst 3750 IOS switches and we have a problem as explained below:

The existing network structure is One core 6509 with WS-X6k-SUP-2GE Supervisor engine (without any MSFC) connected to two 4003 switches over trunks. This core switch is also connected to a router and has vlan 100 on it.

Currently all the 4003 switches and the core switch are on Vlan 100 and all the switches have management interfaces in the Vlan 100 created by using the following command:

set interface sc01

So in this way, all the four 4003 switches have sc01 interfaces with IP addresses in the same subnet (100).

The problem is that these commands are CatOs specific. NOw when we replace a 4003 with one of the Catalyst 3750, we cannot create a management interface as we could in CatOs. In IOS we have to assign an IP address to Vlan1 on each of the catalyst 3750 switches for management.

My question is that Can we create Vlan 100 on all the 3750 switches and assign the IP addresses from subnet 100 (192.168.100.x) for managment. Since 6509 does not have routing capability, so it cannot route between Vlans and hence we cannot create another subnet to give to Vlan 1. If we do this, all the new catalyst 3750 switches will be on the same Vlan 100 with IP addresses from same Vlan 100.

Any suggestion on our scenario will be welcomed.



Re: 4003 CatOs vs 3750 IOS

That is correct just create your layer 2 vlan (100) and then create a layer 3 SVI (interface vlan 100) and assign a address to it just like your sc0 interface on catos . If these were trunked before of course vlan 100 would have to be allowed across the trunk to work and to manage the 3750's . If you want to keep them in vlan 1 just add the ip address to "interface vlan 1 " and make sure the connecting port is set as a switchport in vlan 1 . Also make sure your default gateway is correct or your default route is correct if you do not turn routing off on the 3750.

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