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Need help setting up "one arm routing" between Cat 5500 and 7505 router

Currently I have 5 VLANS setup on my Catalyst 5500 switch, a mix of 10, 10/100, and 100 blades. The 7500 router is the link to the Internet, but the default gateway for all the VLANS is a Windows 2000 server with 5 NICs.

I'd like to setup the 7500 to be the router not only out to the Internet but between the various VLANS. I know the solution probably has something to do with 802.1q trunking and ISL, but I need detailed assistance.

I am not a Cisco expert and am wondering if this is something I should be tackling myself, or should I be paying a CCIE to do it for me? Any information or personal experience would be welcome.

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Re: Need help setting up "one arm routing" between Cat 5500 and


Do you know why the server was setup as the router? There might be a reason that shouldn't be changed.

You are right about the trunking IF each vlan sports a different IP segment. If the vlan members are all of the same IP segment, then the default route just needs to be changed to point to the router. Otherwise, the link between the router and the catalyst needs to be set up as a trunk (isl or 802.1q). For each vlan that is to be trunked, a sub-interface on the router interface must be configured (with encapsulation set to isl or 802.1q (whatever matches the switch)).

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