Comment 2 for bug 1045537

Salvatore, you are correct -R and --no-resolv are equivalent, so we're covered there (I had forgotten that I had already added that option a while back).

If the subnet does not have a nameserver defined, the guest is given the address of the DHCP port running dnsmasq. The way it's setup, dnsmasq will provide local resolution or otherwise forward the request to the configured nameserver. If we default the subnet to a value, then the tenant will lose local network resolution unless the configured server knows how to provide it for the tenant's networks.

The more I've thought about it this evening, I think we should avoid making a change in this area this late in the development cycle because I think the changes have more downside than upside for this late in cycle. I am still open to changes if anyone has a use case where the current behavior is actually worse for tenants than leaving dnsmasq to forward requests.

Tangential:

Looking further down the road for Grizzly, we should take a deeper look at local name resolution. The hostnames we currently construct are of limited use and are not very meaningful They're basically a mangled ip address + default provider configured domain (defaults to fake root level .quantumlocal). Better local hostnames involve changes to both Nova and Quantum to pass names through when creating the port for the guest VM.