Rdiff-backup Quick Introduction

GPL / GNU Tool for Backups

JD P

Algoloma Systems

My Knowledge About Rdiff-backup

• Use extensively for the last 5 yrs

• Local Backups

• Client / Server Backups (versions must match)

• Pull and Push between servers

• ssh tunnels by default for remote connections

• Cross Platform

• Issues with larger files - librsync

Main Features

• rsync-like commands

• Create a mirror

• Keeps increments

• Preserves permissions, ownership, ACL+ and EAs+

• Highly space efficient - diffs and gzipped

• Bandwidth efficient

• Transparent data format

• Cross-platform (Win/Linux/Mac)

• Stats

+ ex libs needed

Similar to rsync commands

$ rdiff-backup source_directory target_directory 

$ rdiff-backup --remove-older-than 60D --force target_directory

$ rdiff-backup --list-increment-sizes target_directory 

Simple Example

# rdiff-backup / user@server::/backups/${hostname}

Rsync-like Options

• Source and Target are specified in rsync format

• Include files

• Exclude files

• Exclude wildcards

• Special files, pipes, devices, sockets, symbolic-links

• userid mapping

rdiff-backup Results

• Target directory

• Target directory/rdiff-backup-data/

• Target directory/rdiff-backup-data/increments/{directories}

• Latest backup appears like a mirror (cp to restore)
• Older versions are stored as incremental, compressed files
• Highly efficient on disk

rdiff-backup Results

• Older files are named:

• default.2011-10-12T03:07:23-04:00.diff.gz
• default.2011-10-29T03:07:23-04:00.diff.gz
• default.2011-11-04T03:07:25-04:00.diff.gz

• Above are /etc/nginx/sites-available/default files

Restore Process

• cp -a remote local

• To restore older versions (complete or a single file), use

 $ rdiff-backup --restore-as-of {time} \

        target_file_or_directory local_file_or_directory 

• Can directly specify an specific file in the increments/ directory (no time spec needed)

Time Specified

• now (most recent backup)

• 2011-10-29T03:07:23-04:00

• 5D - as in 5 days ago

• YYYY/MM/DD, YYYY-MM-DD, MM/DD/YYYY, or MM-DD-YYYY,

• "B" - backup sessions - 0B = current; 5B = 5 sessions ago

Failures

• If the rdiff-backup fails, the next run will automatically roll-back

• Seen 2 failures in 5 yrs.

• Only 1 failure caused a corrupt DB and that was a few yrs ago

Current Backup Script

$ geany a10_rdiff_backup.script.txt

Check on Backups

$ geany a10_rdiff_backup.inc_sizes.txt

Backup Best Practices Checklist

• Automatic & Easy? Yes

• Fast - incremental+? Yes

• Efficient - compressed? Yes

• Secure / encrypted? Yes ssh, but no stored encrypted

• Versioned / not simple mirror? Yes

• Stored Remotely? Yes

• Restoration Verified? Yes

Why Not?

• based on librsync - large files

• Client / Server means the versions need to match.

• 8.04 and 10.04 versions DO NOT WORK together

Warning: Local version 1.2.8 does not match remote version 1.1.15.

• Python not available

• Cross Platform for many, but not all

Learn More

• www.nongnu.org/rdiff-backup/

• Restore Examples

• man rdiff-backup

• blog.jdpfu.com

Questions?

• email: jdp (at) algoloma [dot] com
• Website: http://algoloma.com
• Blog: http://blog.jdpfu.com