We have a development box which we *think* is occasionally sending a blank hostname when it does a DHCP request.
It is getting given a lease fine by dhcpd, but `/etc/hosts` is being populated with the hostname as `.domain-name.example.com`
This causes pdns-recursor to:
1. eat all the ram, getting killed by the OOM killer, then:
2. fail to restart
Assuming its is just falling through the three options given as they are all empty, can we modify https://github.com/vyos/vyos-1x/blob/current/src/conf_mode/dhcp_server.py#L214 to pass an alphanumeric version of the host mac address as a fallback if the other three fail?
If this isn't what is happening, maybe an explicit check that $client_name is set in https://github.com/vyos/vyos-1x/blob/current/src/system/on-dhcp-event.sh#L35 would work as a backstop to prevent these broken entries getting into /etc/hosts