rsync is powerful and easy to use utility to keep files in sync between two servers. The principal way of rsync‘s command structure  is to push files from point A to point B.

rsync -vzru /home/location_A/ user@server2.example.com:/home/location_B/

In the command above, files from 

 on a local disk and server is `pushed` to 

 on 

.

The flags means the following:

The 

 is really useful because it means all directories and subdirectories will be copied.

 means that it won’t copy files again which are the same as the destination receiver

rsync -vrzua -e 'ssh -p 34229' /home/location_A/ user@server2.example.com:/home/location_B/

In the above example, two additional flags were added, namely 

 and 

. These means:

The 

 switch is extremely useful as it will copy all the attributes, e.g. directory permissions and so on.

Typically 

 commands are stored in a 

 to run every XX minutes.

If you want continuous 

, and you are well aware of what it’s going to do to your network traffic, then you need to use an utility called 

 because running one 

 if the previous one hasn’t completed will cause problems.

Here is an example of the flock command:

 produces: