Connect to Vagrant box from docker container running on same host

As described in my last blog post, I could not access my Vagrant box from the Docker container. The reason was that the Vagrant Box had only a NAT interface. This NAT interface is required by Vagrant and you can not change it, e.g. to a Bridged interface. But you can add another interface.

I have added the following entry to the Vagrantfile:

config.vm.network "private_network", type: "dhcp"

After restart the Vagrant Box I determine the assigned IP

$ vagrant ssh -c "ip address"
1: lo:  mtu 65536 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp0s3:  mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 08:00:27:39:18:3c brd ff:ff:ff:ff:ff:ff
    inet 10.0.2.15/24 brd 10.0.2.255 scope global dynamic enp0s3
       valid_lft 86365sec preferred_lft 86365sec
    inet6 fe80::a00:27ff:fe39:183c/64 scope link
       valid_lft forever preferred_lft forever
3: enp0s8:  mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 08:00:27:e2:20:14 brd ff:ff:ff:ff:ff:ff
    inet 172.28.128.3/24 brd 172.28.128.255 scope global dynamic enp0s8
       valid_lft 1170sec preferred_lft 1170sec
    inet6 fe80::a00:27ff:fee2:2014/64 scope link
       valid_lft forever preferred_lft forever
Connection to 127.0.0.1 closed.

From the docker container the box is now reachable using 172.28.128.3 .