On Tue, Feb 27, 2018 at 04:21:59PM -0500, Thomas George wrote: > I tried dnsmasq --dhcp-host=00:15:99:86:11:1F,CLP,192.168.2.13 > > and the response was "failed to create listening socket for port 53: Address > already in use." That means you've already got something else listening on the DNS port. Use some command like lsof -i :53 (or ss or netstat) to find it.