doc rsync - suggest sudo for restricted folder

website/docs/source/v2/synced-folders/rsync.html.md

@@ -35,6 +35,10 @@ can automatically install rsync into many operating systems. If Vagrant
 is unable to automatically install rsync for your operating system,
 it will tell you.
 
+The destination folder will be created as the user initiating the connection,
+this is `vagrant` by default. This user requires the appropiate permissions on
+the destination folder.
+
 ## Options
 
 The rsync synced folder type accepts the following options:
@@ -58,6 +62,7 @@ The rsync synced folder type accepts the following options:
   pattern. By default, the ".vagrant/" directory is excluded. We recommend
   excluding revision control directories such as ".git/" as well.
 
+
 ## Example
 
 The following is an example of using RSync to sync a folder:
@@ -68,3 +73,16 @@ Vagrant.configure("2") do |config|
     rsync__exclude: ".git/"
 end
 </pre>
+
+## Rsync to a restricted folder
+
+If required to copy to a destination where `vagrant` user doesn't have
+permissions, use `"--rsync-path='sudo rsync'"` to run rsync with sudo on the guest
+
+<pre class="prettyprint">
+Vagrant.configure("2") do |config|
+  config.vm.synced_folder "bin", "/usr/local/bin", type: "rsync",
+    rsync__exclude: ".git/"
+    rsync__args: ["--verbose", "--rsync-path='sudo rsync'", "--archive", "--delete", "-z"]
+end
+</pre>