Send mobile DDNS IP adress RUT241

[SweBen]

Hi
I have connected the WAN to a router that I have no control over. My internet traffic goes via WAN and the mobile interface is intended as fail over/for access to my router from the outside. But it only reports the IP address of the WAN, Router which I have no control over. When I turn off the WAN, it sends the IP address from the mobile interface instead. But as soon as I activate the WAN again, it sends the WAN IP address again to the DNS server.
DDNS service protocol is custom.
How to make this work?

[Justinas]

Greetings,

Just to confirm, are you using a custom DDNS service provider with a custom update URL?

If so, you can use crontab to periodically run a curl command that updates the IP address. Here’s how to set it up:

1. Log in to the router via SSH. Instructions can be found here:
   Command Line Interfaces - Teltonika Networks Wiki
2. Run the command crontab -e.
3. When the file opens, press Insert (or i) and add the following line:

*/5 * * * * /usr/bin/curl --interface qmimux0 -k "update_url"

5. Press ESC, type :wq, and hit Enter to save and exit.
6. Restart the cron service using:

service cron restart

The */5 in the crontab entry defines how frequently the command runs, in this example, every 5 minutes.

Note that qmimux0 is the mobile interface name on this router model; yours may differ. You can verify it by running ifconfig.

For additional details on crontab, you may find this page helpful:
[OpenWrt Wiki] Scheduling tasks with cron

Best regards,
Justinas