[Dnsmasq-discuss] (v2.31/Mac OS X) Not listening for DNS requests

[Simon Kelley]

Doug Fields wrote:
> Hello all,
> 
> I successfully built and installed DNSmasq 2.31 on an Intel Mac mini  
> running 10.4.6 using GCC 4.0.1. (I can't say it works because there  
> is no regression test module.) I reconfigured the Makefile and  
> config.h to put all files it uses into /opt/dnsmasq-2.31 or a  
> symlink /opt/dnsmasq to keep everything highly localized. I use the  
> provided Mac OS X startup scripts which runs the application with the  
> command line arguments "-d -n".
> 
> It executes just fine, but does not seem to listen for DNS requests.  
> Indeed, it seems not to even open the port, nor to write any error  
> messages about it. Here's an lsof, with regular files and pipes  
> removed for brevity:
> 
> COMMAND  PID USER   FD     TYPE    DEVICE SIZE/OFF     NODE NAME
> dnsmasq 8836 root    4u    IPv4 0x34a1680      0t0      UDP *:bootps
> dnsmasq 8836 root    5u    IPv4 0x38b9e10      0t0     ICMP *:*
> dnsmasq 8836 root   11u    IPv4 0x34a2ba0      0t0      UDP *:50145
> 
> (bootps is port 67)
> 
> As you can see, there's no listening for port 53. "netstat" also  
> confirms this, neither TCP nor UDP. I have confirmed that the built- 
> in "firewall" is off, but I suppose it's possible that the "System  
> Preferences" application is lying about that, somehow. Even if it  
> were, though, the application should still be listening/opening a  
> socket, even if the ipfw is dropping packets.
> 
> Does anyone happen to have any thoughts as to how to get this to  
> work? I see nothing relevant in /var/log files.

Log entries would be useful, but if you run dnsmasq in the foreground
from a shell and give it the -d flag, it should print stuff to stderr.

If you can get ktrace/kdump to work, a log of exactly which system calls
are being made would be useful. My guess is that something has broken in
the interface enumeration code, since previous versions of dnsmasq have
worked fine, that code has been reworked, and not listening anywhere
implies no interfaces found.
> 
> The non-blank, non-comment lines from my configuration file are  
> reproduced below.
> 
> (I haven't yet tested the DHCP portion... I would in fact like to  
> disable it until after I get DNS working, but it tells me that "en0"  
> is not a recognized interface when I use the appropriate option. I  
> can't figure out how to disable DHCP entirely.)
> 
Comment out the dhcp-range line to disable DHCP.

Cheers,

Simon.