====== Ubuntu - Backups - Synchronize files in a directory between 2 hosts ======

Synchronize files in a directory between 2 hosts using the program rsync. 

<code bash>
rsync -av --delete --rsh="ssh -c arcfour -l root" host1.domain.lan:/disk01/ /disk01/
</code>

  * **-a**:  The files are transferred in "archive" mode, which ensures that symbolic links, devices, attributes, permissions, ownerships, etc. are preserved in the transfer.
  * **-v**:  Increase verbosity.
  * **--delete**:  The destination is always made to look like the source even if files need to be deleted in the destination.  The source's data is never touched.
  * This uses ssh as the remote-shell program as the transport. 
  * **-c** arcfour:  Turns on the lowest grade encryption to speed up the transfer.
  * **-l** root:  Specifies the user to log in as on the remote machine.
  * The source is always named first 
    * host1's /disk01 (source) is the remote host 
  * The destination is always named second.
    * /disk01 (destination) is a local directory. 
  * Trailing / on the source means copy the contents of this directory to the destination.  Without the trailing / the source gets the directory name copied with all it's files in it.