nginx use of UDP ports?

[Maxim Dounin]

Hello!

On Mon, Jun 10, 2019 at 03:59:46PM -0400, Vadim Grinshpun via nginx wrote:

> After setting up nginx to run, I've noticed that 'lsof' shows all nginx
> processes (master + workers) listening on an ephemeral UDP port.
> 
>     nginx 25142   vgrinshp    4u  IPv4 422450236      0t0  UDP
>     127.0.0.1:33226
>     nginx 25144   vgrinshp    4u  IPv4 422450236      0t0  UDP
>     127.0.0.1:33226
>     nginx 25145   vgrinshp    4u  IPv4 422450236      0t0  UDP
>     127.0.0.1:33226
>     nginx 25146   vgrinshp    4u  IPv4 422450236      0t0  UDP
>     127.0.0.1:33226
>     nginx 25147   vgrinshp    4u  IPv4 422450236      0t0  UDP
>     127.0.0.1:33226
> 
> 
> I did not explicitly configure anything that (AFAIK) uses UDP, and I
> could not find anything in the doc that mentions any use of UDP ports by
> nginx.
> The ports seem to be used by nginx even with the most minimal nginx.conf.
> 
> Does anyone here know how/why these ports are used?

By default nginx doesn't use any UDP ports.  What's in your 
config?

-- 
Maxim Dounin
http://mdounin.ru/