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Comment by yardstick | Hacker News Reader

> Even if I did have a changing IP, I have a programmable DNS server that points to the WG server's IP.

I believe that WG resolves the domain only once, upon config load. Not much help if the server IP changes after starting the WG client. Up to the user to realise and stop/start- not so convenient for eg embedded WG clients in travel routers

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If the client is online when the server changes IPs, WireGuard's built-in roaming will handle it transparently: https://www.wireguard.com/#built-in-roaming

If the client is still at the same address it was last time it contacted the server and the server sends data to the client it will be transparently handled. This means that persistent keepalives should be used on both sides. It also still leaves open the possibility of the connection being lost if IP addresses on both sides change during the period between the keepalives or if there is any kind of network disruption preventing traffic from the server to the client during the period the server IP address changes. I had this become an issue for me a few times when I ran a wireguard server at home.

This won't work if the server is being blocked. My mobile ISP blocks incoming UDP traffic unless the phone establishes the "connection" first. Since change of the server's public IP means that "connection" is broken, all unrelated UDP packets never arrive.

Wireguard does not handle this transparently.

The NetworkManager WG integration re-resolves. systemd-networkd doesn't, though it has an open PR for it, though that PR has been stalled for a long time.

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