[Dnsmasq-discuss] Dnsmasq not answering DHCP requests

[Robert Pollai]

Hi Richard,

> This sounds as if some other DNS and DHCP server programs are running.
> Or perhaps dnsmasq is running and owns the ports, but is reading from
> a different configuration file (path can be specified on the
> command-line, there's also a compiled-in default).

I verified that when I stop dnsmasq, the ports disappear from netstat -l. When I start dnsmasq they come back. So it looks like dnsmasq has them.

I start it via the following command in a script:

/volume1/@appstore/dnsmasq/bin/dnsmasq -C /volume1/@appstore/dnsmasq/etc/dnsmasq.conf

For testing purposes I now added logging:

/volume1/@appstore/dnsmasq/bin/dnsmasq -C /volume1/@appstore/dnsmasq/etc/dnsmasq.conf --log-facility=/volume1/@appstore/dnsmasq/log/dnsmasq.log --log-dhcp

I get the following output:

Feb  6 23:13:08 dnsmasq[17719]: started, version 2.52 cachesize 150
Feb  6 23:13:08 dnsmasq[17719]: compile time options: IPv6 GNU-getopt no-DBus no-I18N DHCP TFTP
Feb  6 23:13:08 dnsmasq-dhcp[17719]: DHCP, IP range 192.168.0.100 -- 192.168.0.150, lease time 12h
Feb  6 23:13:08 dnsmasq[17719]: using nameserver 195.202.128.2#53
Feb  6 23:13:08 dnsmasq[17719]: using nameserver 195.202.128.3#53
Feb  6 23:13:08 dnsmasq[17719]: using nameserver 62.40.128.2#53
Feb  6 23:13:08 dnsmasq[17719]: read /etc/hosts - 2 addresses

This shows that it reads the correct config file (it has DHCP and the name servers).

Still, when I start "ipconfig /renew" on a Windows client after disabling the DHCP server in the router the request times out. I already put in dhcp-authoritative in the config file to get dnsmasq to take over everything from the old DHCP server immediately.

So right now I am a bit clueless. I will leave the DHCP in the router switched of and dnsmasq running overnight, maybe the client needs more time to realize that the old DHCP server is gone.

Of course any further advise is greatly appreciated.

Kind regards, Robert

-------- Original-Nachricht --------
> Datum: Sat, 6 Feb 2010 11:35:54 -0600
> Von: "richardvoigt at gmail.com" <richardvoigt at gmail.com>
> An: Robert Pollai <robert.pollai at gmx.at>
> CC: dnsmasq-discuss at lists.thekelleys.org.uk
> Betreff: Re: [Dnsmasq-discuss] Dnsmasq not answering DHCP requests

> On Sat, Feb 6, 2010 at 1:53 AM, Robert Pollai <robert.pollai at gmx.at>
> wrote:
> > Hi Richard,
> >
> > Thanks for your reply!
> >
> >> Is dnsmasq running on the router where the old DHCP software was?  A
> >> separate computer?  Connected how to the network? (e.g. dnsmasq is
> >> wired to the router, clients are a mix of wired and wireless)
> >
> > The previous DHCP server was a router appliance from Linksys. Dnsmasq
> > I run on a NAS from Synology (DS408) with an PPC processor running
> Linux.
> > I compiled dnsmasq there myself. The NAS is wired to the router and all
> > clients I tested so far are wired to the router as well.
> >
> >> What OS?  Could be a firewall/packet filtering issue on either the
> >> dnsmasq computer or the router. (e.g. router firewall is configured to
> >> accept DHCP requests but not bridge them to the rest of the network)
> >
> > I also tested a client that is connected directly to the NAS via a
> switch,
> > So there is no firewall between. The firewall on the NAS is disabled.
> >
> >> Make sure that dnsmasq owns port 67 on its machine by running "netstat
> >> -l" with dnsmasq running and again with dnsmasq stopped.
> >
> > I did that and dnsmasq has port 67 (shown as "bootps") and also 53
> (shown
> > as "domain") for DNS. I tested DNS and it works for machines I have in
> my
> > /etc/hosts (after I commented no-hosts out of the config file). The DNS
> > does not work for the names I put in via the dhcp-host entries.
> 
> This sounds as if some other DNS and DHCP server programs are running.
>  Or perhaps dnsmasq is running and owns the ports, but is reading from
> a different configuration file (path can be specified on the
> command-line, there's also a compiled-in default).
> 
> How are you starting dnsmasq?  Does it behave differently if you run
> it from a root command-line instead of through init scripts?
> 
> >
> > Kind regards, Robert
> >
> > -----Original Message-----
> > From: richardvoigt at gmail.com [mailto:richardvoigt at gmail.com]
> > Sent: 05 February 2010 23:47
> > To: rap.nospam2 at gmx.net
> > Cc: dnsmasq-discuss at lists.thekelleys.org.uk
> > Subject: Re: [Dnsmasq-discuss] Dnsmasq not answering DHCP requests
> >
> > On Fri, Feb 5, 2010 at 3:24 PM,  <rap.nospam2 at gmx.net> wrote:
> >> Hi,
> >>
> >> I am new to dnsmasq and want to replace my routers DHCP with it. So I
> just tried to create my first setup but unfortunately it seems that dnsmasq
> is not answering DHCP requests, my clients requests are timing out.
> >>
> >> I would appreciate any hints on what I could have done wrong or
> generally on how to approach/debug the issue.
> >
> > Is dnsmasq running on the router where the old DHCP software was?  A
> > separate computer?  Connected how to the network? (e.g. dnsmasq is
> > wired to the router, clients are a mix of wired and wireless)
> >
> > What OS?  Could be a firewall/packet filtering issue on either the
> > dnsmasq computer or the router. (e.g. router firewall is configured to
> > accept DHCP requests but not bridge them to the rest of the network)
> >
> > Make sure that dnsmasq owns port 67 on its machine by running "netstat
> > -l" with dnsmasq running and again with dnsmasq stopped.
> >
> >>
> >> Here is my config file:
> >>
> >> - file start -
> >>
> >> # Configuration file for dnsmasq.
> >> #
> >>
> >> dhcp-range=192.168.0.100,192.168.0.150,12h
> >> dhcp-leasefile=/var/packages/dnsmasq/target/leases/dnsmasq.leases
> >> dhcp-authoritative
> >>
> >> no-resolv
> >> no-hosts
> >>
> >> server=(ip deleted)
> >> server=(ip deleted)
> >> server=(ip deleted)
> >>
> >> dhcp-option=option:router,192.168.0.1
> >>
> >> dhcp-host=(mac deleted),adam,192.168.0.100
> >> dhcp-host=(mac deleted),eva,192.168.0.101
> >>
> >> - file end -
> >>
> >> Kind regards, Robert
> >>
> >> _______________________________________________
> >> Dnsmasq-discuss mailing list
> >> Dnsmasq-discuss at lists.thekelleys.org.uk
> >> http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
> >>
> >
> >
> >
> 
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