unbound listening sporadically on 0.0.0.0 high ports when configured for 127.0.0.1 ?

Unbound
1

See https://bugzilla.redhat.com/show_bug.cgi?id=1342105

   from time to time "netstat -l" shows unbound listening on some high-ports not
   bound to 127.0.0.1 - that makes no sense when the service is configured for
   127.0.0.1 only as a local resolver on a inbound mailfilter

   udp 0 0 0.0.0.0:42663 0.0.0.0:*
   563/unbound
   udp 0 0 127.0.0.1:53 0.0.0.0:*
   563/unbound
   udp 0 0 0.0.0.0:12387 0.0.0.0:*
   563/unbound

   unbound.conf
    interface: 127.0.0.1
    access-control: 127.0.0.0/8 allow
    interface-automatic: no

Paul

2

Hi,

   My guess is: UDP sockets for outgoing query
from Unbound to authoritative servers.

  I also see these "listening" UDP sockets at my laptop running unbound
when resolver is under load. And I see no them when no load.

3

Subject: Re: unbound listening sporadically on 0.0.0.0 high ports when
    configured for 127.0.0.1 ?

  My guess is: UDP sockets for outgoing query
from Unbound to authoritative servers.

I also see these "listening" UDP sockets at my laptop running unbound
when resolver is under load. And I see no them when no load.

That was my first thought too, but these entries do not have a
destination IP or port, so it "appears" that these sockets are
listening. Still it could be that perhaps these are sockets
that are starting up for use or something?

Paul

4

Unbound doesn't connect() its UDP query sockets to the destination
IP/port, it uses sendto(), TTBOMK. So I wouldn't think the destination
would show up in netstat (or ss or lsof...) output.