[Dnsmasq-discuss] dnsmasq host being dhcp server to itself [WAS: Web hang ups after repeated access to one site - dnsmasq related?]

[Hugo Heden]

Good day all,

On Fri, Feb 13, 2009 at 4:11 PM, RevRagnarok <DNSMasq at revragnarok.com> wrote:
>
> On Fri, Feb 13, 2009 at 9:55 AM, Chris G <cl at isbd.net> wrote:
>>
>> The problem is specific to my desktop machine (the xubuntu one) which
>> is the one which is running dnsmasq.  When a web site is hung on my
>> machine it's perfectly accessible from browsers on other machines on
>> the same subnet/LAN and using the same router.  However IE within a
>> virtual machine on my machine *can't* access the hung web site.
>
> I'm a little confused here. dnsmasq is more for servers than desktops. Of
> course, you can run it where you like, but it looks like you have your
> desktop acting as a DHCP server, possibly to itself. Or do you ensure the
> machine is on all the time the other machines on the network need an IP? You
> won't get any benefit (that I can think of) running dnsmasq on a stand-alone
> desktop. The OS will cache DNS lookups very similarly on its own.
>

Sorry, I'd like to ask about this to clear it up: It shouldn't be a
problem letting the host running dnsmasq acting as a DHCP-server to
itself, right? (I was about to prepare a blog post/tutorial that
describes and explains that setup.. so it'd be nice with a reality
check.)

 What I was thinking is having something like the following. All hosts
on the network are configured to use dhcp, *including* the host
running dnsmasq. All hosts are equal in that sense. And dnsmasq is the
dhcp server.. /etc/dnsmasq.conf could look like this:

---
 domain-needed
 bogus-priv

 # Let dnsmasq ignore /etc/resolv.conf (because when using the dhcp
 # stuff, that file will be *output* from dnsmasq rather than input)
 no-resolv

 # Upstream DNS server that dnsmasq will forward queries to (an
 # adsl modem perhaps):
 server=192.168.0.254

 # /etc/hosts does not contain anything useful for our purposes.
 # Even for this host (the one running dnsmasq), we use
 # dhcp-host= instead, see below.
 no-hosts

 ### DHCP stuff ###
 domain=lan
 dhcp-range=192.168.1.50,192.168.1.100,12h

 # Some hosts will always get the same, "constant", IP address:
 dhcp-host=hostrunningdnsmasq,192.168.1.101,12h
 dhcp-host=somehost,192.168.1.70,12h
 dhcp-host=otherhost,192.168.1.71,12h
 dhcp-host=yetanotherhost,192.168.1.72,12h

 # Tell dhcp clients what the gateway is (this overrides the
 # default which would have been the host running dnsmasq)
 dhcp-option=option:router,192.168.1.1

---

No other configuration files needed -- on any host -- just let
everybody use dhcp. Super easy. But will this work?

Thanks,

Hugo Heden