devilbox/docs/intermediate/setup-auto-dns.rst

Setup Auto DNS

If you don't want to add DNS records manually for every project, you can also use the bundled DNS server and use it's DNS catch-all feature to have all DNS records automatically available.

Important

By default, the DNS server is set to listen on 1053 to avoid port collisions during startup. You need to change it to 53 in .env via env_host_port_bind.

Table of Contents

local

Native Docker

The webserver as well as the DNS server must be available on 127.0.0.1 or on all interfaces on 0.0.0.0. Additionally the DNS server port must be set to 53 (it is not by default).

• Ensure env_local_listen_addr is set accordingly
• Ensure env_host_port_bind is set accordingly
• No other DNS resolver should listen on 127.0.0.1:53

Prerequisites

First ensure that env_local_listen_addr is either empty or listening on 127.0.0.1.

host> cd path/to/devilbox
host> vi .env
LOCAL_LISTEN_ADDR=

Then you need to ensure that env_host_port_bind is set to 53.

host> cd path/to/devilbox
host> vi .env
HOST_PORT_BIND=53

Before starting up the Devilbox, ensure that port 53 is not already used on 127.0.0.1.

host> netstat -an | grep -E 'LISTEN\s*$'
tcp        0      0 127.0.0.1:53            0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:43477         0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:50267         0.0.0.0:*               LISTEN

If you see port 53 already being used as in the above example, ensure to stop any DNS resolver, otherwise it does not work.

The output should look like this (It is only important that there is no :53.

host> netstat -an | grep -E 'LISTEN\s*$'
tcp        0      0 127.0.0.1:43477         0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:50267         0.0.0.0:*               LISTEN

Linux

On Linux the DNS settings can be controlled by various different methods. Two of them are via Network Manager and systemd-resolved. Choose on of the methods depending on your local setup.

Network Manager

If the prerequisites are met, you can edit /etc/dhcp/dhclient.conf with root or sudo privileges and add an instruction, which tells your local DHCP client that whenever any of your DNS servers are changed, you always want to have an additional entry, which is the one from the Devilbox.

Add the following line to to the very beginning to /etc/dhcp/dhclient.conf:

prepend domain-name-servers 127.0.0.1;

When you do that for the first time, you need to restart the network-manager service.

# Via service command
host> sudo service network-manager restart

# Or the systemd way
host> sudo systemctl restart network-manager

This will make sure that whenever your /etc/resolv.conf is deployed, you will have 127.0.0.1 as the first entry and also make use of any other DNS server which are deployed via the LAN's DHCP server.

If the Devilbox DNS server is not running, it does not affect the name resolution, because you will still have other entries in /etc/resolv.conf.

systemd-resolved

In case you are using systemd-resolved instead of NetworkManager, add the following line to the very beginning to /etc/resolv.conf.head:

nameserver 127.0.0.1

Prevent NetworkManager from modifying /etc/resolv.conf and leave everything to systemd-resolved by adding the following line under the [main] section of /etc/NetworkManager/NetworkManager.conf

dns=none

As a last step you will have to restart systemd-resolved.

host> sudo systemctl stop systemd-resolved
host> sudo systemctl start systemd-resolved

Once done, you can verify if the new DNS settings are effective:

host> systemd-resolve --status

Archlinux Wiki: resolv.conf

MacOS

Modifying /etc/resolv.conf does not work on MacOS, you need to make changes in your System Preferences:

1. Open System Preferences
2. Go to Network
3. Select your connected interface
4. Click on DNS tab
5. Add new DNS server by clicking the + sign
6. Add 127.0.0.1

Windows

On Windows, you need to change your active network adapter. See the following screenshots for how to do it.

In the last screenshot, you will have to add 127.0.0.1 as your Preferred DNS server.

Docker Toolbox

howto_docker_toolbox_and_the_devilbox

MacOS

• env_local_listen_addr must be empty in order to listen on all interfaces
• env_host_port_bind must be set to 53
• Port 80 from the Docker Toolbox virtual machine must be port-forwarded to 127.0.0.1:80 on your host os
• Port 53 from the Docker Toolbox virtual machine must be port-forwarded to 127.0.0.1:53 on your host os

This section needs further proof and information.

Windows

• env_local_listen_addr must be empty in order to listen on all interfaces
• env_host_port_bind must be set to 53
• Port 80 from the Docker Toolbox virtual machine must be port-forwarded to 127.0.0.1:80 on your host os
• Port 53 from the Docker Toolbox virtual machine must be port-forwarded to 127.0.0.1:53 on your host os

This section needs further proof and information.