As described in the comment, systemd will create a broken
/etc/resolv.conf link if there is no file in the base-image (as you
can read in the bug, it is debated if this is a bug or a feature).
The solution is to leave a dummy /etc/resolv.conf file in the image.
Whatever network manager you choose (NetworkManager, glean,
cloud-config, etc) will overwrite this anyway.
It's just that some tools, such as dhclient, get confused with the
broken symlink. This affects you if you're using glean to configure
the network in a DHCP situation, for example -- dhclient won't
configure nameservers and everything goes to heck.
Change-Id: I734834d03e7fdb13f9ab2e86f877b07bf4a84ff9
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