LDAP users now use uids starting at 2000, to prevent confusion with the
users in the host and to potentially allow local users to be created in
the containers as well, if it's ever needed.
# module return 'ignore' instead of 'user_unknown' for local users, which gets
# handled by 'required' properly (without having to specify a verbose custom
# thing).
-account required pam_ldap.so ignore_unknown_user minimum_uid=1000
+account required pam_ldap.so ignore_unknown_user minimum_uid=2000