Backing up with RSYNC

RSYNC is a program that is widely used for backing up data. RSYNC is able to create full, as well as incremental backups, and is pretty easy to use. Moreover, RSYNC can also be used to backup data into remote machines. When backing up to remote machine, RSYNC can utilize SSH which means the communication is being protected by one of the world’s strongest protections. Here’s how RSYNC can be used –

Objective

1. All files in the directory /original needs to be backed up at /backup. The process must be repeated every 10 days.
2. The directory /backupneeds to be backed up at 192.168.10.254:/backup2. The process must be repeated every 15 days.

Phase 1:

We are using the –aoption for ‘archive’ . Archive is used to preserve permissions. The –voption is used for ‘verbose’ output.

root@firefly:~# ls -l /original/

total 0

-rw-r--r-- 1 root root 0 Dec 21 19:40 f1

-rw-r--r-- 1 root root 0 Dec 21 19:40 f2

-rw-r--r-- 1 root root 0 Dec 21 19:40 f3

-rw-r--r-- 1 root root 0 Dec 21 19:40 f4

-rw-r--r-- 1 root root 0 Dec 21 19:40 f5

-rw-r--r-- 1 root root 0 Dec 21 19:40 f6

-rw-r--r-- 1 root root 0 Dec 21 19:40 f7

-rw-r--r-- 1 root root 0 Dec 21 19:40 f8

This is the list of files to be backed up.

root@firefly:~# rsync -av /original/ /backup/

sending incremental file list

./

f1

f2

f3

f4

f5

f6

f7

f8

sent 401 bytes  received 167 bytes  1136.00 bytes/sec

total size is 0  speedup is 0.00

root@firefly:~# ls -l /backup/

total 0

-rw-r--r-- 1 root root 0 Dec 21 19:40 f1

-rw-r--r-- 1 root root 0 Dec 21 19:40 f2

-rw-r--r-- 1 root root 0 Dec 21 19:40 f3

-rw-r--r-- 1 root root 0 Dec 21 19:40 f4

-rw-r--r-- 1 root root 0 Dec 21 19:40 f5

-rw-r--r-- 1 root root 0 Dec 21 19:40 f6

-rw-r--r-- 1 root root 0 Dec 21 19:40 f7

-rw-r--r-- 1 root root 0 Dec 21 19:40 f8

As we can see, all the files have been copied to the destination directory. While using RSYNC, we need to keep in mind that RSYNC is sensitive about the trailing ‘/’ in the source argument. To RSYNC, ‘/original’and ‘/original/’ are not the same thing.

To repeat the task every 10 days, we would add the following crond rule-

Min	Hour	Day of Month	Month	Day of Week	Command
00	02	*/10	*	*	rsync -av /original/ /backup/

 

Phase 2

Here, we would copy the directory /backup from the source machine to the remote machine’s directory /backup2. Here’s how it’s done-

root@localhost:~# rsync -av -e ssh /backup/ 192.168.10.254:/backup2

That wasn’t hard, was it? The only remaining thing to do is to add a scheduled task with the help of crond.

Min	Hour	Day of Month	Month	Day of Week	Command
00	04	*/15	*	*	rsync -av -e ssh /backup/ 192.168.10.254:/backup2

And that’s it. Hope it helps.  ^_^