If OpenVPN client #1 fails, it automatically falls through to OpenVPN client #2. If OpenVPN client #1 eventually recovers, it will automatically return to OpenVPN client #1. That's just the wait it works.
The bigger issue is making sure OpenVPN client #1 actually recovers! Unfortunately, the firmware does very little in that regard. That's why I wrote my own watchdog script for Merlin a few years ago (I haven't used it in a long time, I assume it still works).
Hello, i have installed latest asuswrt merlin on asus rt-ax88 router. I have installed a vpn connection as vpn client with openvpn protocol. When i reboot the router or take it from power, vpn director shows vpn connected status but it is not connected and i have no internet connection. Always...
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IIRC, this was even before
@Viktor Jaep wrote his vpnmon utility. I'm never looked all that deeply into his solution, but I believe it's attempting to solve a similar problem (and perhaps a lot more). I just can't speak to that particular solution since I didn't author it. It may work great (he's an excellent developer). But if there are any relevant issues, he's the one to consult.