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EIGRP layer2 and layer 3

If one switch has only layer 2 and the other switch has layer 2 and 3 will the route have to go through the switch with layer 3 connection even though both have direct layer 2 connections?

Two distribution switches 1 and 2 are connected by a trunk that allows all vlans across including vlans 3 and 10.

Switch 1 and 2 each has a seperate trunk connection to a switch 3 that then connects a single leg connection to a router with an ip address of 1.2.3.4 which is in the vlan 3 network.

Switch 1 runs eigrp protocol and when I run show ip route 1.2.3.4 it shows "connected" *directly connected to vlan 3

Switch 2 runs eigrp protocol and when I run show ip route 1.2.3.4 it shows "eigrp 123" *10.10.10.10 from 10.10.10.10 via vlan 10"

On switch 2 when I run show ip route 10.10.10.10 it shows "connected" *directly connected via vlan 3

On switch 2 when I run traceroute 1.2.3.4 I get 1st hop 10.10.10.10 and 2nd hop 1.2.3.4

Switch 2 has a vlan int for vlan 10 but not no vlan int for vlan 3

Switch 1 has a vlan int for both vlan 10 and 3

Is this happening because switch 2 does not have an ip address/interface in vlan 10 and then switch 1 is advertises 1.2.3.4 across vlan 10 to switch 2 even though there is trunk between switch 1 and 2 that allows vlan 10 and 3?

I originally expected to see sh ip route 1.2.3.4 as *directly connected to vlan 3 on both switch 1 and 2?

Both switch 1 and switch 2 have a layer 2 connection to vlan 3 but only switch 1 has a layer 3 connection to vlan 3
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Sr.Net.Eng
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Top Expert 2011
Commented:
That is exactly why. Since the router is sitting in vlan 3. Switch two must get routed out vlan 10 to get to vlan 3.
SouljaSr.Net.Eng
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Top Expert 2011

Commented:
Move the router to vlan 10 and remove the vlan 3 interface from it and add to switch 2 and you will get the same thing on switch 1.
SouljaSr.Net.Eng
CERTIFIED EXPERT
Top Expert 2011

Commented:
I meant "Move the router to vlan 10 and remove the vlan 3 interface from switch 1 and add to switch 2 and you will get the same thing on switch 1. "
SouljaSr.Net.Eng
CERTIFIED EXPERT
Top Expert 2011

Commented:
I meant "Move the router to vlan 10 and remove the vlan 10 interface from switch 2  and replace with int vlan 3, and you will see a similar result."

Boy do we need an edit button.