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Virtual Interfaces

I have a 2600 router and because I only have 1 Fast Ethernet interface and 2 switches, I am connecting both switch throught the FA port and then making the FA port have 2 virtual interfaces. FA0/0.1 and FA0/0.2. What do I need to do to allow the router to talk to the two switches. With 2 virtual interfaces.


Re: Virtual Interfaces

How many VLAN's are you running? It sounds like two, but I bet only one. If you're only running one you don't need sub-interfaces. If you are running multiple VLANS, you may need more sub-interfaces. Each VLAN (not switch) needs a default gateway and that is what the sub-interface on the router is providing. If you have 10 VLANs and they all need to talk, you'll need 10 sub-interfaces. If you only have 1 VLAN, you don't need any sub-interfaces, as you can use the FastEthernet interface for the gateway. Please provide more information for us to help you.

Re: Virtual Interfaces


its not about how to allow router to talk to the two switch... you can connect one switch to the router and other switch to the one of the switch port of the switch which is connected with the router... but you have to worry about the subinterfaces then only when you have the different subnets as well as multiple vlan in your network... as you know that two different valn can not communicate with each other with out layer3 functionality so at that time you need to have the multiple subinterface... or if you are using the different subnet like one subnet from class A and class C then you can have multiple subinterface with the different subnet address so you can configure the gatway address in your host in order to make communication between different subnet...

in sort its all depends on your network design...

hope this helps

rate this post if it helps



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