Re: [libvirt] [PATCH] network: permit upstream forwarding of unqualified DNS names

This resolves the issue that prompted the filing of https://bugzilla.redhat.com/show_bug.cgi?id=928638 (although the request there is for something much larger and more general than this patch). commit f3868259ca0517212e439a65c9060868f673b6c9 disabled the forwarding to upstream DNS servers of unresolved DNS requests for names that had no domain, but were just simple host names (no "." character anywhere in the name). While this behavior is frowned upon by DNS root servers (that's why it was changed in libvirt), it is convenient in some cases, and since dnsmasq can be configured to allow it, it must not be strictly forbidden. This patch restores the old behavior, but since it is usually undesirable, restoring it requires specification of a new option in the network config. Adding the attribute "forwardPlainNames='yes'" to the <dns> elemnt does the trick - when that attribute is added to a network config, any simple hostnames that can't be resolved by the network's dnsmasq instance will be forwarded to the DNS servers listed in the host's /etc/resolv.conf for an attempt at resolution (just as any FQDN would be forwarded). When that attribute *isn't* specified, unresolved simple names will *not* be forwarded to the upstream DNS server - this is the default behavior. ---