Connecting to the host

Sometimes it can be helpful to start a temporary server on your computer and scan it from the Docker environment. To do that, just configure your scan to use the IP address 172.17.0.1: inside a Docker container, this address refers to the host machine. (Some Windows and Mac editions of Docker also define a DNS name for the host, host.docker.internal.)

Note that you might need to adjust your firewall to allow connections from the virtual Docker networks. By default, these are all given addresses in the range 172.*.*.*, equivalent to 172.0.0.0/8 in CIDR notation. Using the ufw command, for example, you might do something like this to allow all connections from that range:

ufw allow from 172.0.0.0/8 to any