File README.kerberos of Package openssh
This version of the Kerbros/GSSAPI support avoids DNS lookups
for Kerberos-related names. These DNS lookups were problematic
for dialup users because they would lead to excessive delays
if DNS was not reachable.
If you do use Kerberos, please make sure you edit the server and
client configuration files as follows:
... lots of other options ...