[Rspamd-Users] rspamd listening on udp ports on 0.0.0.0

[Vsevolod Stakhov]

On 09/04/2019 20:54, Hagen Bauer wrote:
> Hi to all
> 
> 
> 
> what is the background that rspamd ist listening on a lot of udp ports.
> 
>  netstat -tulpn | grep rspamd
> tcp        0      0 127.0.0.1:11332         0.0.0.0:*
> LISTEN      1381/rspamd: main p
> tcp        0      0 127.0.0.1:11333         0.0.0.0:*
> LISTEN      1381/rspamd: main p
> tcp        0      0 127.0.0.1:11334         0.0.0.0:*
> LISTEN      1381/rspamd: main p
> udp        0      0 0.0.0.0:35152           0.0.0.0:*
>        2744/rspamd: rspamd
> udp        0      0 0.0.0.0:51586           0.0.0.0:*
>        2744/rspamd: rspamd
> udp        0      0 0.0.0.0:51631           0.0.0.0:*
>        2741/rspamd: rspamd
> udp        0      0 0.0.0.0:59824           0.0.0.0:*
>        2744/rspamd: rspamd
> udp        0      0 0.0.0.0:43475           0.0.0.0:*
>        2743/rspamd: rspamd
> udp        0      0 0.0.0.0:43482           0.0.0.0:*
>        2741/rspamd: rsp
> 
> and a lot more that I cut off.
> 

As I've replied in GH issue that are sockets for DNS resolver pool.
There is no such thing as "listening" in UDP so I can hardly understand
what are you asking about. Rspamd uses `recvfrom` system call to read
replies from DNS server(s).