persistent keepalive: start sending immediately

Rather than only start sending the persistent keepalive packets when the
device first sends data, this changes it to send the packets immediately
on `ip link set up`. This makes things generally seem more stateless,
since the administrator does not have to manually ping the endpoint.

Of course, if you have a lot of peers and all of them have persistent
keepalive enabled, this could cause a lot of unwanted immediate traffic.
On the other hand, if all of those peers are at some point going to be
sending packets, this would happen anyway. I suppose the moral of the
story is that persistent keepalive is a feature really just for clients
behind NAT, not for servers, and it should be used sparingly, which is
why we've set it off by default in the first place.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

0 files changed, 0 insertions, 0 deletions