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Use a single cisco 1841 to route between subnets

Can I use a single cisco switch to route between to subnets?  I have obtained a 1841 and was playing around with it thinking that I could do this.  I have 0/0 and 0/1 configured each with different subnet ip address. (ie. and

Many moons ago I had a quick intro to IOS but have gotten very rusty.  

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1 Solution
Just use those two IP that you assigned for the 1841 interfaces as gateways for respective subnets
PlazaPropAuthor Commented:
if I do that the traffic destined for outside (ie internet) wont be routed. Unless the 1841 had another nic or i impliment another router.
jmeggersSr. Network and Security EngineerCommented:
Then configure subinterfaces and a trunk from the switch, with the other interface going to the Internet.

Interface fa0/1
No ip address

Interface fa0/1.35
Ip address

Interface fa0/1.36
Ip address

On a Cisco switch:

Interface fax/y
Switchport trunk encapsulation dot1q
Switchport mode trunk
Switchport trunk allowed VLAN 35,36

PlazaPropAuthor Commented:
I guess I cannot do what I would like to do without installing another NIC in the router.  

Jmeggers, I cannot do what you say because it is not a switch with routing.  It is a Router.   A managed services router at that.  

I wanted to easily (or shall I say cheaply with the existing equipment)  implement it at our network so that I could crate a separate network and route between them.  

PlazaPropAuthor Commented:
Given that the router has only 2 nic's I cannot do what I want without getting another nic card.
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