NetworkManager and its [mis]use of resolvconf

[Michal Soltys <soltys ziu info>]

Hi,

While testing NM recently with multiple connections active, I realized that NM 
merges all the resolver information into single resolv.conf file and then 
submits that as a single interface to resolvconf (e.g. can be seen as
/run/resolvconf/interfaces/NetworkManager)

This bascially inhibits resolvconf from managing this in any sensible way.

Resolvconf itself have options to:

- mark interface as exclusive (-x)
  meaning: in case of multiple interfaces provided, only one's
           information will be used; in case of multiple exclusive
           interfaces, the most recent one is used; in case local
           resolver is present basically no-op

- mark interface as private (-p)
  meaning: provided information is used only for the relevant domain;
           this basically requires local resolver and makes simple
           split dns config; particular resolv.conf's servers won't be
           used for "." forwarding either.
           Among supported resolvers it can:
           - configure unbound
           - configure dnsmasq
           - configure named
           - configure powerdns

Basically - it can gracefully do everything(?) that NM tries to do by itself 
(e.g. recent dns-priority feature). Why not rely on resolvconf ?

IF NetworkManager submitted one resolv.conf per connection - and exposed 
'exclusive' and 'private' flags per defined connection - that would be pretty 
much a perfect way to manage dns information from them - whether local 
resolver is or isn't present.

Are there any plans/chances to adjust NetworkManager so it behaves this way 
(at the very least start with providing single interface per connection 
instead of current one interface per all connections) ?