[Dnsmasq-discuss] No more random source port

[Risto Suominen]

Hi Albert,

2017-03-20 20:30 UTC+02.00, Albert ARIBAUD <albert.aribaud at free.fr>:
>
> I don't kow about dnsmasq per se, but the range of ports an application
> can use is controlled by the kernel -- on my 16.04 Xubuntu, that is
> defined by /proc/sys/net/ipv4/ip_local_port_range. Does your system
> limit this range?
>
32768 60999
>
> Not sure what you mean exactly. "Same port" as what?
>
Same as in previous request. The router is another forwarder for the
DNS requests (dnsmasq is the first).

To give an example:

- $ host xxx 127.0.1.1 -> no response (via dnsmasq to router)
- $ host xxx 192.168.1.1 -> response (directly to router)

The difference is that 'host' uses varying random source ports, and
'dnsmasq' uses one preallocated random source port.

Risto