[Swan] Tunnel is up, but getting udp port xxxx unreachable

[Paul Wouters]

On Wed, 21 Dec 2022, Brendan Kearney wrote:

> Subject: [Swan] Tunnel is up, but getting udp port xxxx unreachable

> connecting client is seen replying with ICMP udp port unreachable messages:

> VPN Server config:
> conn rac
>     leftsubnet=0.0.0.0/0
>     right=%any
>     rightaddresspool=192.168.152.50-192.168.152.99

[...]

> VPN Client config:
> conn rac
>     left=%defaultroute
>     leftsubnet=0.0.0.0/0
>     leftmodecfgclient=yes
>     # Remote Definitions
>     right=host.domain.tld
>     rightid=192.168.152.254
>     rightsubnet=0.0.0.0/0

You are handing out IPs in the same /24 as the LAN itself? That might
cause problems if machines in the LAN are a true /24. You would need
proxyarp and what not and it complicates things.

I'd recommend splitting of the addresspool into a real seperate network.

Paul