vagrant-dns

vagrant-dns allows you to configure a dns-server managing a development subdomain. It works much like pow, but manages Vagrant machines.

Installation

$ vagrant plugin install vagrant-dns

Attention: As of v2.0.0, vagrant-dns requires vagrant >= 1.9.6 (because it ships with a more modern version of ruby)
If you get an error like rubydns requires Ruby version >= 2.2.6. while installing, you probably need to upgrade vagrant.
Alternatively, you can install an older version of vagrant-dns like this: vagrant plugin install --plugin-version="<2" vagrant-dns

Usage

In addition to your networking config, configure a toplevel domain and a hostname for your machine. Optionally, configure a set of free matching patterns. Global configuration options can be given through the VagrantDNS::Config object:

Vagrant.configure("2") do |config|
  #...

  config.dns.tld = "test"

  config.vm.hostname = "machine"

  config.dns.patterns = [/^(\w+\.)*mysite\.test$/, /^(\w+\.)*myothersite\.test$/]

  config.vm.network :private_network, ip: "33.33.33.60"
end

# optional
VagrantDNS::Config.logger = Logger.new("dns.log")

Then, register the DNS server as a resolver:

$ vagrant dns --install

On OS X, this will create a file /etc/resolver/test, which tells OS X to resolve the TLD .test by using the nameserver given in this file. You will have to rerun --install every time a tld is added.

You can delete this file by running:

$ vagrant dns --uninstall

To also delete the created config file for this TLD (~/.vagrant.d/tmp/dns/resolver/test in our example) run:

$ vagrant dns --purge

Then, run the DNS server:

$ vagrant dns --start

And test it:

$ scutil --dns
...
resolver #8
  domain   : test
  nameserver[0] : 127.0.0.1
  port     : 5300
...
$ dscacheutil -q host -a name test.machine.test
name: test.machine.test
ip_address: 33.33.33.10

You can now reach the server under the given domain.

Note: Mac OS X is quite different from Linux regarding DNS resolution. As a result, do not use dig or nslookup, but dscacheutil instead. Read this article for more information.

Finally, stop the server using:

$ vagrant dns --stop

The DNS server will start automatically once the first VM is started.

You can list the currently configured dns patterns using:

$ vagrant dns --list

(Keep in mind, that it's not guaranteed that the running server uses exactly this configuration - for example, when manually editing it.)
The output looks somewhat like this:

/^.*mysite.test$/ => 33.33.33.60
/^.*myothersite.test$/ => 33.33.33.60

Where the first part of each line is a regular expression and the second part is the mapped IPv4. (=> is just a separator)

Multi VM config

We can use multivm configuration and have dns names for host.

• Use below given vagrant config

  BOX_IMAGE = "ubuntu/xenial64"
  WORKER_COUNT = 2
  Vagrant.configure("2") do |config|
    (1..WORKER_COUNT).each do |i|
      config.vm.define "worker#{i}" do |subconfig|
        subconfig.dns.tld = "test"
        subconfig.vm.hostname = "vagrant"
        subconfig.dns.patterns = "worker#{i}.mysite.test"
        subconfig.vm.box = BOX_IMAGE
        subconfig.vm.network "private_network", ip: "10.240.0.#{i+15}"
      end
    end
  end

• vagrant up
• Execute : vagrant dns --install
• Test via: ping worker2.mysite.box or worker1.mysite.box

VM options

• vm.dns.tld: Set the tld for the given virtual machine. No default.
• vm.dns.tlds: Set multiple tlds. Default: [tld]
• vm.dns.patterns: A list of domain patterns to match. Defaults to [/^.*{host_name}.{tld}$/]

Global Options

• VagrantDNS::Config.listen: an Array of Arrays describing interfaces to bind to. Defaults to [[:udp, "127.0.0.1", 5300]].
• VagrantDNS::Config.ttl: The time-to-live in seconds for all resources. Defaults to 300 (5 minutes).
• VagrantDNS::Config.auto_run: (re)start and reconfigure the server every time a machine is started. On by default.
• VagrantDNS::Config.check_public_suffix: Check if you are going to configure a Public Suffix (like a Top Level Domain) in a VMs tld(s) config, which could mess up your local dev machines DNS config. Possible configuration values are:
  • false: Disables the feature.
  • "warn": Check and print a warning. (Still creates a resolver config and potentionally messes up your DNS) At the moment, this is the default because lots of projetcs used to use "dev" as a TLD, but this got registered by google and is now a public suffix.
  • "error": Check and prevent the box from starting. (Does not create the resolver config, it will also prevent the box from starting.)

Using custom domains from inside the VM (VirtualBox only)

If you need to be able to resolve custom domains managed by this plugin from inside your virtual machine, add the following setting to your Vagrantfile:

Vagrant.configure(2) do |config|
  # ...
  config.vm.provider "virtualbox" do |vm_config, override|
    vm_config.customize [
      "modifyvm", :id,
      "--natdnshostresolver1", "on",
      # some systems also need this:
      # "--natdnshostresolver2", "on"
    ]
  end
end

By default, the Virtualbox NAT engine offers the same DNS servers to the guest that are configured on the host. With the above setting, however, the NAT engine will act as a DNS proxy (see Virtualbox docs). That way, queries for your custom domains from inside the guest will also be handled by the DNS server run by the plugin.

Issues

• A records only
• No IPv6 support
• OS X only (please read: Platform Support before ranting about this).
• Not automatically visible inside the box (special configuration of your guest system or provider needed)