Title: #790: Lookahead resolving of host names
Since the PR contains some patches that I wrote, I will not review it, at least not in
What I noticed is that the first patch touches the IPA and AD providers, but not the plain
kerberos provider. @thalman mentioned he'd squash the first and the one-before-last
patches into one.
See the full comment at https://github.com/SSSD/sssd/pull/790#issuecomment-476614350