Ok, I figured it out. Common Name is "client", and I thought it would use the username as CN. That's why my ccd file wasn't read. Adding directive username-as-common-name as custom configuration on server side solved the issue.
Indeed the issue was that the file in ccd wasn't read, because when I copied it to a DEFAULT file in the same folder then the iroute statement was activated and the traffic works between the lan's.
Another issue is that on the client router I need to add a rule to POSTROUTE chain otherwise...
I'm attempting to set up a lan to lan vpn between two Asus routers running Merlin firmware. I've read through numerous threads on this topic in the forum but none seems to match the issue I see.
Server side:
Network: 172.26.2.0/24
Router: Asus RT-AC3200 with Merlin fw 384.13_10
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