Re: [libvirt] [PATCH] network: don't add "no-resolv" if we still need DNS servers from resolv.conf

On 03/17/2017 12:58 PM, Jiri Denemark wrote: > On Fri, Mar 17, 2017 at 12:33:14 -0400, Laine Stump wrote: >> It was pointed out here: >> >> https://bugzilla.redhat.com/show_bug.cgi?id=1331796#c4 >> >> that we shouldn't be adding a "no-resolv" to the dnsmasq.conf file for >> a network if there isn't any <forwarder> element that specifies an IP >> address but no qualifying domain. If there is such an element, it will >> handle all DNS requests that weren't otherwise handled by one of the >> forwarder entries with a matching domain attribute. If not, then DNS >> requests that don't match the domain of any <forwarder> would not be >> resolved if we added no-resolv. >> >> So, only add "no-resolv" when there is at least one <forwarder> >> element that specifies an IP address but no qualifying domain. > ... > So what if the network is isolated and supposed to only resolve names > according to its database. Such network does not have any <forwarder/> > element and yet no-resolve should be added in the configuration. You forced me to remember that I had fixed exactly that hole a *long time* ago (far before <forwarder> was added). I looked it up and found commit 513122ae: https://bugzilla.redhat.com/show_bug.cgi?id=723862 which adds no-resolv if the network is isolated. I was momentarily afraid that the no-resolv added in that patch had been "messed with" at some later time, causing a regression in my fix, but found that it's still there (look around line 1216). So in the case of an isolated network, we still add no-resolv, no matter whether we've added it due to <forwarders> or not.