GRE Tunnel Issues

Dear All,

Today I do a small test to see what is GRE Feature on Peplink 380 (firmware 6.2.2). I got a strange issue so I need your kindly support.

Let’s see the network diagram first.

In the above topology, the Peplink will create a GRE Tunnel to Router A via the Local Link. Peplink Wan1 detail configuration is below:

  • Connection method: GRE.
  • Routing mode: NAT.
  • WAN:
  • WAN Subnet: /24.
  • WAN Default Gateway:
  • Remote GRE Host:
  • Tunnel Local IP Address:
  • Tunnel Remote IP Address:
  • Outgoing NAT IP Address:

I can see the GRE packet between Pelink and Router A but I cannot ping on Peplink from Router A.
In addition, when I do a ping test from Peplink to, packet loss happen (image below).

Can anybody explain me how the GRE feature of Peplink work?



GRE on WAN interface is used to connect to ISP. Please find here for more details based on your design.