Can not Ping GRE destination after set up MPLS VPN

[Maivoko]

I am doing a lab for MPLS VPN + IPSec GRE

can not Ping after setup GRE and MPLS VPN

only can Ping using MPLS VPN IPSec VTI which no GRE

do I need to configure MTU to make GRE pingable? What MTU value should be configured ?

[Georg Pauwen]

Hello,

the recommended values are:

interface Tunnel1

ip mtu 1400

ip tcp adjust-mss 1360

That said, I am not sure that this is causing the reachability problem. Can you post the configs of both sides ?

[mark.chennell]

I think alittle more info is needed and a clearer topology ....

The thing with GRE tunnels is to check that the tunnels are actually up, i always like to configure a keep-alive to get around this.

[Maivoko]

I succeed to do the lab

it do not need to change MTU

i discover that I just type wrong tunnel destination ip address