—delete—Deletes extraneous files from destination directories.
—delete-excluded—Also deletes excluded files from destination
directories.
—exclude-from=/home/matt-exclude.txt—Prevents backing
up files or directories listed in this file. (It is a simple list with each
excluded directory on its own line.)
—backup—Creates backups of files before deleting them from a
currently existing backup.
—backup-dir=‘date +%Y-%m-%d’—Creates a backup directory
for the previously mentioned files that looks like this: 2013-07-08. Why
this format for the date? Because it is standard, as outlined in ISO 8601
(see http://www.iso.org/iso/home/standards/iso8601.htm). It is clear,
works with scripts, and sorts beautifully, making your files easy to find.
-av—Tells rsync to use archive mode and verbose mode./—Denotes the directory to backup. In this case, it is the root directory of
the source, so everything in the file system is being backed up. You
could put /home here to backup all user directories or make a nice list
of directories to exclude in the file system.
/media/externaldrive/backup/seymour—Sets the destination
for the backup as the /backup/seymour directory on an external
hard drive mounted at /mount /externaldrive.To restore from this backup to the same original location, you reverse some of
the details and may omit others. Something like this works nicely:
Click here to view code image
matthew@seymour:~$ rsync --force --ignore-errors --delete --delete-
excluded
/media/externaldrive/backup/seymour /
This becomes even more useful when you think of ways to script its use. You
could create an entry in crontab, as described in Chapter 14, “Automating
Tasks and Shell Scripting.” Even better, you could set two computers to allow
for remote SSH connections using private keys created with ssh-keygen,
as described in Chapter 19, “Remote Access with SSH, Telnet, and VNC,” so
that one could backup the files from one computer to the other computer
without requiring manual login. Then you could place that in an automated
script.