Networking
tcpdump – debug DHCP
tcpdump -i <interface> -vvv -s 0 port bootps
dnsmasq – run in front-end and show DHCP log
dnsmasq -u nobody --dhcp-authoritative -P 4096 -C /var/dnsmasq.conf -d --log-dhcp
dhclient – show detail
dhclient -v <interface>