Failover with OpenVPN

[Col8eral]

I have an RT-AX88U running Merlin.

I have setup up 4G LTE failover dongle. Fails over and fails back perfectly.

However, i can no longer connect into the OpenVPN server running on the router. I use the ASUS DDNS service.

How can I still access the OpenVPN server when the router has failed over to the 4G LTE backup?

Many thanks

 

[ColinTaylor]

Does your 4G LTE service allow unsolicited remote connections and provide a public IP address?

If so check whether your DDNS address is being updated with the new IP address when the failover happens.

 

[Col8eral]

Thank you. How do I do that? Is it the logs?

 

[ColinTaylor]

I don't use DDNS myself but I believe there are fairly obvious messages in the router's System Log each time the DDNS update runs.

Also verify the address by doing an nslookup on the DDNS name and seeing if it matches your failed over address.

 

[Col8eral]

when i do a nsloopup on my asus ddns name i get a different IP on my primary wan to the 4G fail over.

 

[ColinTaylor]

when i do a nsloopup on my asus ddns name i get a different IP on my main address to the 4G fail over

"different" as in the IP address of your other WAN interface, or different as in not the same as either of them?

Are you sure your 4G LTE service gives you a public IP address, and not a private or CGNAT address? What are to first two octets of the 4G LTE address as seen on the router's Network Map page? [Click on the globe icon for the active LTE WAN connection]