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Development Tools Installing a Ruby Development Environment Installing a Ruby Development Environment Installing the Treehouse VM on Mac

Alexis Donnard
Alexis Donnard
4,931 Points
Posted by Alexis Donnard
Alexis Donnard
4,931 Points

Vagrant cannot forward the specified port on this VM

Hi, After installing Ruby, I ran the 'rails new testapp' command and went to my localhost:3000 and this worked perfectly. However, now that I want to install the VM Treehouse, when I run the 'vagrant up' command, I got the following error message:

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 3000 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: 3000, 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.

Do you know how I can fix this?

Thanks in advance.

Alexis

Alexis Donnard
Alexis Donnard
4,931 Points
Alexis Donnard
Alexis Donnard
4,931 Points

Ok so I found the answer if someone encounters the same pb: Just go to your 'projects' folder and open the VagrantFile. You'll get a line with: config.vm.network :forwarded_port, guest: 1234, host: 1234, and you only need to change the guest and host nb :)