[squid-users] dns_nameservers with port?

[Alex Rousskov]

On 2026-02-15 10:42, listy wrote:

> Can _dns_nameservers_ take port number?

Currently, dns_nameservers rejects name server addresses with port numbers:

      WARNING: rejecting '127.0.0.1:5353' as a name server, because
          it is not a numeric IP address


> with:
> _dns_nameservers 10.9.4.7:5350_
> Squid starts but when I try to use it, Squid logs:
> 
> ...
> WARNING: idnsSendQuery: Can't send query, no DNS nameservers known!
>      current master transaction: master56
> ...
> 
> What is (not)happening here?

After all dns_nameservers addresses were rejected (see above), Squid may 
start but will fail to send any DNS queries, logging the above error 
message. I hope that future Squid versions will refuse to start instead 
(i.e. the "rejecting ..." behavior described above will become a fatal 
configuration error).


FWIW, you can use a non-default port number, one for all custom name 
servers, by building Squid sources with NS_DEFAULTPORT macro defined and 
set to the desired port value. IMO, this hack is not an officially 
supported feature and may disappear without warning or diagnostics.


HTH,

Alex.