Dmvpn tunnel appears to block http/https over Rodgers Fixed Wireless 5G Cradlepoint

[dmooreami]

Just  swapped over to a Rogers 5G wireless "cradlepoint" for a backup in one of my locations.  Now when we failover test, http/https will not connect to endpoint in either datacenter  on the other side of the tunnel. I have my IP MTU set to 1400. It worked great with the old DSL circuit. 

Browsing out to the internet there are zero issues. I can play youtube videos but yet can't open call manager "self-care" web  portal in datacenter1 or Solarwinds Orion login at datacenter2

Traffic is routing correctly down the tunnel, traceroute to two separate datacenters verified using tracecrt from local pc.

Called Rodgers and they said their unit is in pass-through mode, not NAT mode and is directly connected to ethernet port on my router.

Could this be a MTU problem on my side of the tunnel?

If I modify my side of the dmvpn tunnel to say IP MTU 1376, will the other side automatically drop its MTU side to 1376?

Any other suggestions welcome.

[Francesco Molino]

Hi

Does the other end have mtu path discovery? If yes, it will check the MTU it has to go with otherwise, it won’t change.

You said, MTU is set 1400. Did you setup tcp mss? If not, you can apply it on your tunnel with the command:

ip tcp adjust-mss 1360

You can apply this on both end and see how it goes. It should solve your issue.