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Supporting VLAN Layer 3 interfaces on multiple switches

Level 1
Level 1

My company is going to be testing our DRP this weekend and part of this test will simulate access to my server room being cut off. I have a meshed LAN Backbone where I have the vlans propagated everywhere outside of the server room via VTP. This is all great. The server room is where my CAT 4506 is and happens to be the switch where all the L3 interfqaces are for my Vlans for Wireless, Voice etc.

Is there a way to duplicate the layer 3 interfaces on a second switch that is outside of the Server room? assume all else is working. I have never done this and ownder if there is a dynamic way for this to happen versus me shutting down the physical interfaces to the server room, then recreating the L3 interfaces on the "New" core switch. I guess i could create then and put them admin down until I need them too. I thought about Dynamic routing protocols in the LAN but that changes the environment quite a bit. Not sure if this is what I want at this point.

any ideas?



5 Replies 5

John Blakley
VIP Alumni
VIP Alumni


Being that they're L3 interfaces, could you run hsrp between the 2 switches? Then you could have your primary switch configured as your primary in the server room and your other switch would be standby. Then when they shut your server room down, the interfaces will still be up based on the virtual IP. The only downside would be that it would require you to reconfigure what you have now, and move the physical address to the virtual ip and then come up with a new physical address.



HTH, John *** Please rate all useful posts ***

hmm... I like it. I thought baout this after I wront my post. Check out this basic drawing I did. this is my LAN Backbone. Just running STP and VTP.

I am guessing that I should put the standby at the MPOE switch as this is where my standby Firewall will also be. This is where all my telco comes into the building.

I am curious if they are going to shut down access to the servers completely what is the point then doesn't matter because users can't access any resources any ways.

well I tried to keep it simple and in the context of what im doing. But since you asked, We have DRP site elsewhere connected to the MPLS network where we have identified critical systems that will be made available outside the normal server room environment. This is done in our VMware infrastructure and SANs.

I am just oging to shut down the iinterfaces for the  2 paths into the server room

Oh ok bleh sorry but thank you for answering I was just curious was overthinking it

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