Dhcp_host_domain_ng.py?

What does it mean?

Sep  7 19:12:54 turris /dhcp_host_domain_ng.py: Add_lease, hostname check failed
Sep  7 19:12:54 turris /dhcp_host_domain_ng.py: Add_lease, hostname check failed
Sep  7 19:12:54 turris /dhcp_host_domain_ng.py: Add_lease, hostname check failed
Sep  7 19:12:54 turris /dhcp_host_domain_ng.py: DHCP unknown update operation
Sep  7 19:12:55 turris /dhcp_host_domain_ng.py: Refresh kresd leases

Please continue on other threads like DHCP unknown update operation