''' ... Vagrant cannot forward the specified ports on this VM, since they
would collide with another VirtualBox virtual machine's forwarded
ports! The forwarded port to 3010 is already in use on the host
machine. ... '''
I'm going a little bit pedantic here but still.. If the forwarded port is in use by the host machine the error message should not say "since they would collide with another VirtualBox virtual machine's forwarded ports".
The first time I got this error I checked out all the running vms vagrantfiles to see if the ports clash. It took me some time to figure out thad I had another process running on the host machine binding that port.
+1 . I don't think this issue is overly pedantic, it's a confusing error message that could be clarified by rewording it to something like "The forwarded port to [PORT] is already in use on the host machine, or would collide with another VirtualBox machine's forwarded ports."
+1. I just spent a couple of minutes trying to debug this.
Better error message on port collision. #1141
This is fixed now