NetworkManager vs Cacheing nameserver

[Patrick O'Callaghan]

On Tue, 2010-01-05 at 18:22 +1030, Tim wrote:
> On Tue, 2010-01-05 at 00:39 +0000, Patrick O'Callaghan wrote:
> > I installed bind and tried to use it as a basic cacheing nameserver,
> > which in principal just means running named and
> > pointing /etc/resolv.conf to 127.0.0.1. However resolv.conf keeps
> > getting overwritten by NetworkManager,
> 
> Are you able to configure your DHCP server?  On my network, my DHCP
> server tells all the clients to use my DNS server, because that's how
> I've configured it, and everything is hunky dory.

Not in general. This is a netbook and I'm moving around. On my home
desktop I have a wired connection and IIRC everything Just Works.

> If you're trying to ignore information from your DHCP server (because
> you can't configure it), then you need to play with configuring your
> DHCP client.  That used to be by the /etc/dhclient.conf file, but I seem
> to recall that you'd put a special copy of the options into some other
> location, one read by Network Manager.

There is no dhclient.conf file anywhere in the system.

> > I notice an excessive number of "Resolving foo ..." messages from
> > Firefox and Chrome, i.e. no cacheing is being done as far as I can
> > tell. Note that I didn't touch named.conf or any other config files.
> 
> If the domains being resolved set silly zero-second (or similar) record
> life data, then your caching name server is going to honour that.  But
> are you sure that those warnings are about the same records over and
> over?

I haven't checked in detail but I'll make a note of that.

> I've noticed that, at least in the past, Firefox will do some of its own
> caching.  i.e. The next time it needs a connection to example.com,
> Firefox uses the same IP without consulting a DNS server.  It's been
> necessary to quit and restart Firefox to test changes to DNS records.

I'm using Chrome at the moment, as it's lighter weight on a netbook.

> You might want to play with the dig tool and your name server.

I've been using dig to check lookups.

poc