Tarsnap - Online backups for the truly paranoid

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Simple usage

Even the world's best backup service is useless if it's not used properly. Fortunately, there's only two steps to proper backups:

  1. Making backups
  2. Testing / restoring backups

Remember that thanks to deduplication, only unique data will be uploaded. It's better to create "too many" backups rather than "not enough"!

Assumptions

This page assumes that:

  • You installed Tarsnap to /usr/local/bin/.
  • You are using a configuration file that has keyfile and cachedir set.
  • You have a /root directory.
  • You would like to use Tarsnap as the root user. If necessary, become root by running:
    su

If any of those assumptions are incorrect, no problem! Simply adjust the directory names (below), or add --keyfile and --cachedir, as appropriate.

Step 1: Making backups

First, create a backup script; this may be run manually, or scheduled to run automatically.

Step 1A: Backup script

  1. Create a /root/tarsnap-backup.sh script containing:
    #!/bin/sh
    /usr/local/bin/tarsnap -c \
    	-f "$(uname -n)-$(date +%Y-%m-%d_%H-%M-%S)" \
    	/MY/DATADIR
    Please note:
    • We recommend using the full path, as this avoids potential problems with $PATH and crontab.
    • Replace /MY/DATADIR as appropriate.
    • The -f command defines the "archive name" in which your data is stored on the Tarsnap servers.
      • The command $(uname -n) automatically turns into your computer's $HOSTNAME.
      • Optionally, change the format of the timestamp.
  2. Make the script executable, then run it whenever you want:
    chmod u+x /root/tarsnap-backup.sh
    /root/tarsnap-backup.sh
  3. Check that you can restore these backups with Step 2: Testing / restoring backups.

Step 1B: Automatic backups (optional)

  1. Add this to your crontab:
    14 5 * * * /root/tarsnap-backup.sh
  2. Wait a day for the script to run automatically.
  3. Check that you can restore these backups with Step 2: Testing / restoring backups.

Step 2: Testing / restoring backups

Second, check that the previous backup(s) worked.

  1. See a list of archives:
    tarsnap --list-archives | sort
  2. Restore one of those archives:
    tarsnap -x -f mybackup-2015-08-09_19-37-20
  3. Check that the files and directories are what you expect.

More advanced usage

There are many other options available with tarsnap. We recommend reading the tips, then the general usage documentation or read the man pages.