[Dnsmasq-discuss] No more random source port

Risto Suominen risto.suominen at gmail.com
Mon Mar 20 18:54:51 GMT 2017

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

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


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