How to debug “Vagrant cannot forward the specified ports on this VM” message

Question

I\'m trying to start a Vagrant instance and getting the following message:

Vagrant cannot forward the specified ports on this VM, since they
would collide wi         


        

Answer 1

If you use Proxifier (or a similar app) try closing it first. This was a problem I experienced due to Proxifier on OSX 10.9.

Answer 2

The way out:

1. $ vagrant suspend
2. $ vagrant resume

Answer 3

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

config.vm.network "forwarded_port", guest: 80, host: 8080,

auto_correct: true

end

The final :auto_correct parameter set to true tells Vagrant to auto correct any collisions. During a vagrant up or vagrant reload, Vagrant will output information about any collisions detections and auto corrections made, so you can take notice and act accordingly.

https://www.vagrantup.com/docs/networking/forwarded_ports.html

Answer 4

As message says, the port collides with the host box. I would simply change the port to some other value on the host machine. So if I am getting error for

config.vm.forward_port 80, 1234

then I would change it to

config.vm.forward_port 80, 5656

As 1234 might be used on my host machine.

For actually inspecting ports on any machine, I use the tcpview utility for that OS and get to know which port is used where.

Answer 5

Watch out, your Vagrantfile is not the only one being used when bringing up a Vagrant box/instance.

When you get this:

~/dev/vagrant user$ vagrant reload
Vagrant cannot forward the specified ports on this VM, since they
would collide with some other application that is already listening
on these ports. The forwarded port to 8001 is already in use
on the host machine.

To fix this, modify your current projects Vagrantfile to use another
port. Example, where '1234' would be replaced by a unique host port:

  config.vm.network :forwarded_port, guest: 8001, host: 1234

Sometimes, Vagrant will attempt to auto-correct this for you. In this
case, Vagrant was unable to. This is usually because the guest machine
is in a state which doesn't allow modifying port forwarding.
~/dev/vagrant user$ 

You are actually not only using the Vagrantfile from ~/dev/vagrant but also the one from your "box" distribution .box file which is typically located here:

~/.vagrant.d/boxes/trusty/0/virtualbox/Vagrantfile

And if you have a look at it you'll see it has plenty of default port mappings:

$ cat ~/.vagrant.d/boxes//trusty/0/virtualbox/Vagrantfile
$script = <<SCRIPT
bzr branch lp:jujuredirector/quickstart /tmp/jujuredir
bash /tmp/jujuredir/setup-juju.sh
SCRIPT

Vagrant.configure("2") do |config|
  # This Vagrantfile is auto-generated by 'vagrant package' to contain
  # the MAC address of the box. Custom configuration should be placed in
  # the actual 'Vagrantfile' in this box.

  config.vm.base_mac = "080027DFD2C4"
  config.vm.network :forwarded_port, guest: 22, host: 2122, host_ip: "127.0.0.1"
  config.vm.network :forwarded_port, guest: 80, host: 6080, host_ip: "127.0.0.1"
  config.vm.network :forwarded_port, guest: 8001, host: 8001, host_ip: "127.0.0.1"
  config.vm.network "private_network", ip: "172.16.250.15"
  config.vm.provision "shell", inline: $script

end

# Load include vagrant file if it exists after the auto-generated
# so it can override any of the settings
include_vagrantfile = File.expand_path("../include/_Vagrantfile", __FILE__)
load include_vagrantfile if File.exist?(include_vagrantfile)

So, go ahead and edit this file to remove the offending colliding forwarding port(s):

  config.vm.network :forwarded_port, guest: 22, host: 2122, host_ip: "127.0.0.1"
  config.vm.network :forwarded_port, guest: 80, host: 6080, host_ip: "127.0.0.1"
  # config.vm.network :forwarded_port, guest: 8001, host: 8001, host_ip: "127.0.0.1"

By:

~/dev/vagrant user$ cp ~/.vagrant.d/boxes//trusty/0/virtualbox/Vagrantfile ~/.vagrant.d/boxes//trusty/0/virtualbox/Vagrantfile.old
~/dev/vagrant user$ vi ~/.vagrant.d/boxes//trusty/0/virtualbox/Vagrantfile

and watch out for other Vagrantfiles inclusion i.e.:

include_vagrantfile = File.expand_path("../include/_Vagrantfile", __FILE__)

And now it works:

$ vagrant up
Bringing machine 'default' up with 'virtualbox' provider...
==> default: Importing base box 'trusty'...
==> default: Matching MAC address for NAT networking...
==> default: Setting the name of the VM: vagrant_default_1401234565101_12345
==> default: Clearing any previously set forwarded ports...
==> default: Clearing any previously set network interfaces...
==> default: Preparing network interfaces based on configuration...
    default: Adapter 1: nat
    default: Adapter 2: hostonly
==> default: Forwarding ports...
    default: 22 => 2122 (adapter 1)
    default: 80 => 6080 (adapter 1)
    default: 22 => 2222 (adapter 1)
==> default: Running 'pre-boot' VM customizations...
==> default: Booting VM...
==> default: Waiting for machine to boot. This may take a few minutes...
    default: SSH address: 127.0.0.1:2222
    default: SSH username: vagrant
    default: SSH auth method: private key
    default: Warning: Connection timeout. Retrying...
==> default: Machine booted and ready!
==> default: Checking for guest additions in VM...
==> default: Configuring and enabling network interfaces...
==> default: Mounting shared folders...
    default: /vagrant => /Home/user/dev/vagrant/vagrant-docker
==> default: Running provisioner: shell...
    default: Running: inline script
...

Hope this helps.

Answer 6

I fixed it this way:

1. vagrant suspend
2. Close Project on RubyMine IDE
3. vagrant resume
4. Open Recent on RubyMine IDE