With things like homebrew you kind of forget that you’re not on Linux, and some things might actually work differently. Trying to connect to a host database server from the container using 172.17.0.1 didn’t work out.

After few hours, figuring out that everything’s setup right, you’re not going crazy, you stumble upon this note:

The host has a changing IP address (or none if you have no network access). From 18.03 onwards our recommendation is to connect to the special DNS name host.docker.internal, which resolves to the internal IP address used by the host. This is for development purpose and will not work in a production environment outside of Docker Desktop for Mac.

The gateway is also reachable as gateway.docker.internal.

docs.docker.com

And everything works like charm:

[root@e70e59cdb3c3 /]# ping host.docker.internal
PING host.docker.internal (192.168.65.2) 56(84) bytes of data.
64 bytes from 192.168.65.2 (192.168.65.2): icmp_seq=1 ttl=37 time=0.951 ms

[root@e70e59cdb3c3 /]# mysql -u root -h host.docker.internal -p
Enter password:
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 350