At least a [ hostname should contain 3 parts, the name of the host, the domain and the Top Level Domain (TLD).
For example:
- hostname: www
- domain: daemonforums
- TLD: org
So yours is missing a third ingredient
I don't know what exactly your Windows clients are doing, but somehow they are resolving
home.io to
www.nic.io which has the 193.223.78.212 IP address. Probably a failed, or wrongly interpreted
double reverse name lookup.
If you have an OpenBSD firewall you could run tcpdump there and watch the DNS requests from those Windows clients to see what is happening:
Assuming you have a
re0 NIC:
[
# tcpdump -vvvv -ni re0 -s1500 port 53
It also would be informative if you could post the contents of
/etc/resolv.conf and
/etc/hosts.
An alternative to all this debugging is to simply configure a DNS server in your local LAN and making sure that each host has a proper local hostname of at least three elements.