-Z, --read-ethers

Read /etc/ethers for information about hosts for the DHCP server. The format of /etc/ethers is a hardware address, followed by either a hostname or dotted-quad IP address. When read by dnsmasq these lines have exactly the same effect as --dhcp-host options containing the same information. /etc/ethers is re-read when dnsmasq receives SIGHUP. IPv6 addresses are NOT read from /etc/ethers.