Vagrant rsync-auto doesn't seem to update files in a virtual machine, on Mac

Question

Vagrant rsync-auto doesn't seem to update files in a virtual machine, on Mac

I have been using Vagrant on Windows for a while without problems with rsync-auto. Having tried setting up my mailbox on a MacBook Air, there are no errors in the command, but the folder does not seem to be updated with new files. What's happening?

This is the setting I have in my Vagrantfile:

config.vm.synced_folder "/Users/<username>/<path>/<to>/<dir>", 
  "/var/www/html/<dir>", type: "rsync", rsync__exclude: ".git/",
  owner: "root", group: "root"

When I SSH into VM, I see that the changed date of the files does not change.

Conclusion vagrant rsync-auto

$ vagrant rsync-auto
==> default: Doing an initial rsync...
==> default: Rsyncing folder: /Users/<username>/<path>/<to>/<dir>/ => /var/www/html/<dir>
==> default:   - Exclude: [".vagrant/", ".git/"]
==> default: Watching: /Users/<username>/<path>/<to>/<dir>
D, [2014-09-19T15:09:36.087365 #38613] DEBUG -- : Adapter: considering TCP ...
D, [2014-09-19T15:09:36.087457 #38613] DEBUG -- : Adapter: considering polling ...
D, [2014-09-19T15:09:36.087532 #38613] DEBUG -- : Adapter: considering optimized backend...