If you install the dnsmasq package then that package starts a standalone instance of the dnsmasq program and resolv.conf will contain a line `nameserver 127.0.0.1` which tells the resolver to consult that instance of the dnsmasq program, which will by default forward DNS queries to the nameservers which would otherwise have been directly consulted by the resolver.
The answer to the question "shouldn't those DNS servers should be included in /etc/resolv.conf regardless of the presence of dnsmasq?" is "no". Resolvconf doesn't list any nameserver addresses after any loopback address, unless TRUNCATE_NAMESERVER_LIST_AFTER_LOOPBACK_ADDRESS=no in /etc/default/resolvconf. When dnsmasq is installed does DNS function correctly? If so then there is no problem. ** Description changed: By default, when installing ubuntu-desktop (and when installing some other packages as well), apt will also install dnsmasq as a dependency. - When dnsmask is installed, and static IP addresses are used, resolv.conf + When dnsmasq is installed, and static IP addresses are used, resolv.conf creates a nearly empty /etc/resolv.conf file. The file only contains entries for localhost and the search domain. If static IP addresses are defined in /etc/network/interfaces, then shouldn't those DNS servers should be included in /etc/resolv.conf regardless of the presence of - dnsmask? + dnsmasq? ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: resolvconf 1.78ubuntu2 ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6 Uname: Linux 4.4.0-21-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 Date: Wed Apr 27 08:34:24 2016 InstallationDate: Installed on 2016-04-26 (0 days ago) InstallationMedia: Ubuntu-Server 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.3) PackageArchitecture: all SourcePackage: resolvconf UpgradeStatus: No upgrade log present (probably fresh install) -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to resolvconf in Ubuntu. https://bugs.launchpad.net/bugs/1575644 Title: resolvconf doesn't create the correct /etc/resolv.conf file when static IP addresses are used Status in resolvconf package in Ubuntu: Incomplete Bug description: By default, when installing ubuntu-desktop (and when installing some other packages as well), apt will also install dnsmasq as a dependency. When dnsmasq is installed, and static IP addresses are used, resolv.conf creates a nearly empty /etc/resolv.conf file. The file only contains entries for localhost and the search domain. If static IP addresses are defined in /etc/network/interfaces, then shouldn't those DNS servers should be included in /etc/resolv.conf regardless of the presence of dnsmasq? ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: resolvconf 1.78ubuntu2 ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6 Uname: Linux 4.4.0-21-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 Date: Wed Apr 27 08:34:24 2016 InstallationDate: Installed on 2016-04-26 (0 days ago) InstallationMedia: Ubuntu-Server 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.3) PackageArchitecture: all SourcePackage: resolvconf UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/resolvconf/+bug/1575644/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp