Trunk issue

Unanswered Question
Jun 5th, 2008
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I have ethernet handoff link between two 2811 routers. following is the topology.


These 2811s are equiped with Nm16 switch card.

Trunk is configured on ethernet interfaces. There are 2 VLANs: VLAN1 and VLAN 110. VLN1 is management and VLAN110 is DATA.

My problem is when e1 goes down and comes up, VLAN1 goes into forwarding state in trunk. But VLAn110 stucks up.

VLAn 110 doesnt goes in forwarding state. When ever I manually shut/no shut respective trunk interfaces VLAn 110 goes in forwarding state.

Why this is happening? Can anybody throw somelight on this?


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paolo bevilacqua Thu, 06/05/2008 - 14:57
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It seems you're using bridging on the serial interface.

Bridging when not necessary often gives unexpected results and is a poor design practice.

Do a regular routing setup and you will have no issues.

sdoremus33 Fri, 06/06/2008 - 08:49
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As earlier post move from L2 by issuing no switchport and add the ip address to the interface which puts in Routed mode L3 also add to port channel group


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