I'm creating a web server in Ubuntu , I installed the DNSmasq and I'm having problems with port 53 .
I can not find a solution, can you help me out?
P.D.: In the Virtual Box configuration, in the networks section, I'm using the Bridge Adapter option (in case it has something to do)
You should disable the systemd-resolv process that you can see when executing the command (check which process is listening on port 53):
sudo netstat -tupln | grep -w LISTEN
To disable that service you must edit the configuration file /etc/systemd/resolved.conf there you must add or edit the flag DNSStubListener=no reboots and you can run your service dnsmasq without problem.