VTP update over L2TPV3 fails

Unanswered Question
Jun 10th, 2009


we are expanding a trunk port over a L2TPV3 tunnel (in port mode):

trunk port <-> 2811 <-tunnel-> 2811 <--> trunk port

Everything works fine but VTP updates are failing.

Sniffer shows that VTP packets are out of order after the tunnel. There a 3 packets and order after the tunnel is 1,3,2. So packet #2 is as big as MTU and will be transfered fragmented over the tunnel. It looks like the router on the far end of the tunnel delivers reassembled packets later.

We can't increase MTU in the tunnel network. Decreasing MTU in the LAN is also no option.


Is there a way to limit VTP packet size on the VTP server switch?

Is there a way to force tunnel routers to deliver fragmented and reassembled packets in original order?

Thanks in advance


I have this problem too.
1 vote
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)


This Discussion