Arc not connecting after router unplugged

[Axel_Lesch]

@Robert_F @Christian_Platt @Toine_Frijters
I noticed this issue a while ago and commented on it, as did @Tim_Rhodes.
For me, a core reboot of my Nuc was enough to get everything working again.

B1208 Roon ARC UPnP configuration fails after ISP internet outage

Just to confirm, I had exactly the same issue with ARC from day one: As soon as I had to reboot my router or just the modem for some reason, the connection via UPnP regularly stopped working afterwards. A core reboot fixed this with UPnP and ARC working again. I did not try to reboot only the server. (That’s why I configured a port forwarding rule for my router instead of UPnP, so everything runs perfectly now without any interruptions or failures.) My router: ASUS RT-AX86U Modem in bridge …