Troubleshooting WireGuard connections

[Jason A. Donenfeld]

Hi Riccardo,

Based on those tcpdump timestamps, it looks like the handshake
response happens nearly immediately after the handshake initiation.
Yet from your description, it appears only after many moments. In my
experience, tcpdump blocks like this when it has to do too many DNS
resolutions and the resolver is slow. You might get a more accurate
picture of what is going on if you additionally pass `-n` to tcpdump,
which should make the packets appear more instantaneously.

Jason