On 02/25/2013 09:08 PM, Gao Yongwei wrote:
>
> I thinks it's better that if we can put dnsmasq args or options in a
> conf file, so we can do some custom through this conf file.
> I've added a Bug 913446 in redhat bugzilla,but seems no one take care
> of this bug?

This has been discussed extensively on the list before, and we
specifically *don't* want to do it. Gene Czarcinski even submitted a
patch that would do it, and that patch was rejected (and I *think* he
agreed with our reasoning :-)

The problem is that when you allow a user to silently subvert the config
that is shown in libvirt's XML, and the system stops working, the user
will send a plea for help to irc/mailing list (or open a ticket with
their Linux support vendor), and the people they ask for support will
say "show us the output of 'virsh net-dumpxml mynetwork'", which they
will send, and then a comedy of errors will ensue until someone finally
realizes that there is some "extra" configuration that the user isn't
telling us about.

There are two solutions to that:

1) add an element for the specific option you want to control in
libvirt's network XML. Some knobs are already there, and others are
being added.

2) add a private "dnsmasq" namespace to libvirt's network xml, with
provisions for directly passing through dnsmasq commandline options from
the xml to the conf file. This would be similar to what has already been
done for qemu: http://libvirt.org/drvqemu.html#qemucommand

The difference between these and the idea of simply allowing a
user-written conf file is that everything about the network's config
would then be available in "virsh net-dumpxml $netname".

As far as the bug you've filed, it takes awhile for bugs to be triaged.
(At a first glance, it seems reasonable to add such an option, since it
is a standard part of the dhcp protocol. We might need to do something
about specifying different units for the lease time.)