> *Other notes:*
> - We attempted to use the setup described here
> https://lists.fedorahosted.org/pipermail/sssd-users/2015-February/002648.html,
> however clients attempt to authenticate to each domain and fail as they are
> only joined to b.site.com.

This should work as long as the ldap_sasl_authid is set properly for
both domains (I haven't tested that, though..but it should work..)

Thanks, that appeared to do the trick, and was only necessary to add that for the remote domains.