Ever have a very minimal Unix server (say a DNS server or firewall) that has more configuration than you can afford to lose, but which doesn't need a complicated backup program?
You want to back it up over the network to a management machine, but most backup solutions will take more than five minutes to install. What to do?
Stupid Backup is your solution!
It's a very simple shell script that's trivial to understand and modify. This README is substantially longer than the actual script!
The script simply reads a list of host names on the command line, ssh's to each box in turn, tars up things you feel need backing up, and saves those tar files on the local machine in a directory for each remote host.
It keeps a few days (five by default) of the tar files on hand, and is smart enough not to remove any old backups if the host is unreachable.
Just edit one or two lines, throw it into cron, and go!
You can be up and running in about five minutes. Really!
First, the account you run this from needs to be able to log in over ssh without a password as root to the machines being backed up.
The only sane way to do this is public key authentication, with the
local account's public key on a line in the remote machine's root
account's .ssh/authorized_keys file.
(You can check that this was done correctly by then doing
ssh root@remotehost echo hi
If that works without asking for a password, you're good to go.)
Second, there are also two lines near the top of the stupid-backup
shell script that you can edit.
One sets the variable NUM to the number of days of backups to
keep. It is set to five by default. Feel free to change it if you like.
The other, BACKUPDIR, sets the directory on the current machine in
which to keep the backups. You will need to edit that one.
(It should also go without saying that the directory the variable points to needs to exist.)
Third, every remote machine being backed up will also need two files
in that machine's /etc directory. One is /etc/backup.inc, which
needs a set of lines saying which directories to back up. For example:
etc
var
root
u/perry
The second is a file named /etc/backup.exc, which is a set of files
and directories in the included directories not to back up. For
example:
etc/postfix/*.db
var/db
var/run/*
var/spool/postfix/private/*
var/spool/postfix/public/*
var/tmp/*
backup.inc and backup.exc are just fed as command line options to
tar, so there's nothing at all special about how they work.
Once you have edited stupid-backup and have set up the backup.inc
and backup.exc files on each box, and made sure the local machine
can ssh without a password to the root account on the remote machine,
you can test that everything is working this way (replace "host1" etc.
with the names of the machines you are backing up):
stupid-backup host1 host2 host3
When you are sure that works, just put a line in the crontab for the account doing the backups that looks sort of like this:
15 2 * * * /home/youraccount/bin/stupid-backup host1 host2 host3
E-mail will be sent to that account every night listing the hosts that have been backed up and showing the backup files that are present.
Years ago, I (Perry Metzger) needed to back up a couple of boxes, and most solutions available seemed to be designed for doing complicated incremental backup schemes across a large number of machines. That was far more than I required.
I hacked this together instead in a few minutes. It has served me well ever since, with minimal changes.
Stupid Backup is too stupid to claim rights to, so I have dedicated it to the public domain.
To the extent possible under law,
Perry E. Metzger
has waived all copyright and related or neighboring rights to
Stupid Backup.
This work is published from:
United States.
I'm actively interested in comments, suggestions and improvements to this program. Please let me know, either with a bug report on Github or by email. (My address is "perry" at the domain "piermont.com")