Hello, Jakub,
It seems it was a configuration deficiency. As per
https://fedorahosted.org/sssd/ticket/1633#comment:1 seems that explicitly
stating which DNS domain to query solves the issue.
I am not sure why it works without the /etc/hosts entry and the configs. I
guess it falls back to using the kerberos domain as the DNS suffix if the
machine suffix is not available.
Cheers,
Ballock