Host name lookup failure using hostbased authentication

[Thomas Köller]

There is a nasty problem when using hostbased authentication:

[thomas at sarkovy ~]$ journalctl -l -f | grep -Fe 'sshd['
Okt 22 15:20:54 sarkovy sshd[35034]: userauth_hostbased mismatch: client 
sends htpc.koeller.dyndns.org, but we resolve 192.168.0.2 to 192.168.0.2
Okt 22 15:20:54 sarkovy sshd[35034]: Connection closed by authenticating 
user thomas 192.168.0.2 port 36284 [preauth]
^C

Note that hostname/address lookups work in either direction:

[thomas at sarkovy ~]$ host htpc.koeller.dyndns.org
htpc.koeller.dyndns.org has address 192.168.0.2
htpc.koeller.dyndns.org has IPv6 address fd46:1ffa:d8e0::2
[thomas at sarkovy ~]$ host 192.168.0.2
2.0.168.192.in-addr.arpa domain name pointer htpc.koeller.dyndns.org.

What's wrong here?

Thomas