Rsync:
According to wikipedia, rsync was first announced in June of 1996.
See link: http://en.wikipedia.org/wiki/Rsync
In its basic form, rsync is used to copy files from one folder to another folder and maintain a synchronized copy of the files, when activated.
The folders can be on the same computer, different computers on the same network, or on another network. It uses a delta algorithm to compare new files to old and only transfer enough bytes to compare, make changes, and delete when necessary. There are many options when using rsync. Read the man pages, read the internet forums, and do what works best for you.
I use ssh and rsync to maintain a copy of about 100GB worth of important data that changes on a weekly basis. Rsync is loaded on the source and destination machines. I ssh between the machines and initiate rsync on the destination machine. Bandwidth is not an issue for me as they are both on a gigabit router so I do not use compression. IF you are going across the internet, use compression to more efficiently use bandwidth.
My rsync command looks something like this:
rsync -r root@<server>:/folder1/folder2/folder3/ /home/Rsync/folder1/
From the destination server, the command starts rsync, login as root on the source server,
and begins rsync on the source server. (You should have rsync loaded on both servers)
The "r" says recursive. (get all the underlying folders and files).
The first path ending in folder3/ is my source directory.
This is followed by a space and the path to my destination folder.
I end each path in a "slash" but the syntax is up to you.
I don't save the owners/rights because of the type of data I am saving.
If you are backing up user folders, you should save owners/rights to simplify any restore you might need to make.
I have just briefly touched on rsync and how it works for me. Study it, read the man pages, read the forums on the net, and let it work for you.
NOTE:
This post was later than I expected. We had record 100 year snowfall and low temperatures in my area of Oklahoma and several things were put on hold for a few days. Through the use of linux and ssh, we were able to maintain servers, computer support, backups, etc., from our homes, as the power and internet stayed up.
Have fun computing and until next time,
Jim
