IMPALA-5253 made it necessary that nodes use the FQDN when connecting to each other when using SSL. Often the hostname command only returns the short host name and omits to the domain part. Daemons that advertise themselves with this short name then experience connection issues. If the DNS configuration cannot be fixed, the full hostname can be passed to daemons through the -hostname flag.
IMPALA-4978 tracks resolving this correctly from Impalas side.
Sailesh Mukil - FYI.