If you are new to Rsync, please visit our How To Use Rsync – The Basics post. In it we break down what Rsync is and its basic usage. It will provide you with a good background to understand the details of using Rsync between computers.
Rsync Between Remote Computers
Although Rsync does a great job of synchronizing files between local folders it really shines when working between remote computers. And if you are familiar with using ssh from the command line, you will find it relatively easy to use Rsync.
The basic command is pretty simple, and so long as you have ssh available and rsync installed on the remote machine(s) this format will work.
From a remote source:
rsync [options] [user]@[source computer]:[source folder] [destination folder].
Or to a remote source:
rsync [options] [source folder] [user]@[destination computer]:[destination folder].
Or between two remote computers:
rsync [options] [user]@[source computer]:[source folder] [user]@[destination computer]:[destination folder]
Rsync Between Remote Computers with SSH Examples
rsync email@example.com:~/source/file /home/user/destination/
rsync /home/bdoga/source/file firstname.lastname@example.org:~/destination/
rsync email@example.com:~/source/file firstname.lastname@example.org:~/destination/
In these examples the “file” will be placed in the destination directory on either the local or remote computers. Also for the remote machines you will notice that a single “:” colon was used. This indicates that rsync should use a remote shell, typically SSH to make the connection. And it will fire up rsync on the remote side of the connection to handle the details. Additionally you can force the connection to use an rsync daemon by specifying a “::” double colon instead.
Using the native rsync protocol alone is a little faster, because it doesn’t have any SSH connection overhead. But it also is not an encrypted connection, so there are trade offs to either option. I typically just use the SSH option since I typically have SSH already available and configured on my servers.
Some more useful options
I already discussed the “-a” archive option, in my Rsync Basics post. But it is my goto option for ensuring an exact copy, permissions and all is made. Now that we are connecting to a remote machine, the “-z” (zip) option gets the chance to shine a bit. When you are transferring data over the internet you may not always have a fast connection. The Zip option will ensure that, potentially, much less bandwidth is required to transfer your data.
Another option that is sometimes useful with remote connections is the “-P” (–Progress –Partial) option. This will display the current progress of the file that is being copied. And it will keep “partial” copies of files if a transfer gets interrupted during the sync. In my opinion the Progress that is displayed is great if you are transferring larger files. But if you are moving lots of little files the output is not very useful. And the overhead to produce the Progress output can cause some noticeable slowdown in a transfer.
One additional par of options are the –include, and –exclude options. They are pretty self explanatory, in that they allow you to include or exclude specific files from your sync. These options can be used to fine tune what you are copying from a directory, and ensure you only get what you want. –include ‘R‘ –exclude ‘‘
More Remote Computer Rsync Examples
rsync -avzhP email@example.com:/home/user/source/ /home/user/destination/
rsync -avzhP --include '*.sql' --exclude 'dbname*.sql' firstname.lastname@example.org:/home/user/source/ /home/user/destination/
In the above example only .sql files would be copied from the source. But no .sql files where the file name started with “dbname” would be copied. Or you could add multiple entries to ensure you got all the files you needed in one go.
rsync -avzhP --include '*.html' --include '*.php' email@example.com:/home/user/source/ /home/user/destination/
In this next example, all .html and .php files will be copied. But no other files.
Rsync continues to be a super useful utility in your systems administration toolkit. Now that you have a good understanding of its usage you are ready to tackle some of Rsync’s more advanced features. Or learn how other programs like Rdiff-backup build upon it to create an awesome tools. And a big thanks to some other sites which we have referenced over the years. Check them out here, and here.