backup recovery oss

[email protected] . www.trivadis.com . Info-Tel: 0800 87 482 347 . Date 24. Oct. 2008. Page 1 / 34

Backup using OpenSource utilities Daniel Steiner . Consultant . 24. Oct. 2008

1 Preface This document presents an overview of the available Open Source backup softwares. It will show several possibilities and alternative, in order to give you a feeling about the power of these Open Source solutions. If you search for backup software on http://www.sourceforge.net, you get more than 700 results. This demonstrates the large range of Open Source software for backup and recover purposes. The scope of this document will of course be reduced and focuses on the most interesting softwares. Most OpenSource backup utilities are based on Linux / Unix standard tools like tar, cpio, bzip2, gzip, ssh, rsync, mt and mtx. Therefore an easy installation is always possible, indeed all these tools are part of Linux distributions or other UNIX derivatives. This document describes only a few, but very useful applications. The range of software varies between Enterprise level and very simple software applications. The chapter, Software list, presents some important Open Source backup projects. From this list, We picked a few applications to describe them more in deep:

BackupPC: Network backup server, which writes the backups to disk only

Bacula: Network backup server, which can handle tapes and tape libraries

Monderescue: Disaster recovery tool, which can create directly bootable medias

SystemRescueCD: Bootable CD, which contains a lot of tools for backup and recover procedures

Installserver based recovery: It's also possible to restore using an installation system

Trivadis backup module: Perl script which collects partition, LVM and software raid information and creates a partimage or compressed tar archive

rdiff-backup: Mirror application based on rsync

rsnapshot: Mirror application based on rsync


2 Software list

2.1 Data backup

Below a not complete list of OpenSource backup utilities. Yellow marked tools are presented in this document:

Software Web URL Notes

BackupPC: http://backuppc.sourceforge.net/info.html

Amanda: http://amanda.zmanda.com/

Bacula: http://www.bacula.org/

Cedar Backup: http://cedar-backup.sourceforge.net/

Cobian Backup: http://www.educ.umu.se/~cobian/cobianbackup.htm Windows only! Delphi

rsnapshot: http://www.rsnapshot.org/

rdiff-backup: http://www.nongnu.org/rdiff-backup/

snapbackup: http://snapbackup.com/

lbackup: http://connect.homeunix.com/lbackup/doku.php?id=overview

synbak: http://www.initzero.it/products/opensource/synbak/

Restore: http://restore-backup.com/

2.2 Cloning or disaster:

Also not complete list of cloning or disaster OpenSource software:


CDBkup: http://cdbkup.sourceforge.net/

partimage: http://www.partimage.org/Main_Page

SysrescuCD: http://www.sysresccd.org/Main_Page

Clonezilla: http://clonezilla.sourceforge.net/

CloneIt: http://www.ferzkopp.net/joomla/content/view/12/14/

FOG (Freee Ghost): http://freeghost.no-ip.org/index.php?option=com_frontpage&Itemid=1

Mondoarchive: http://www.mondorescue.org/, ftp://ftp.mondorescue.org/

snapbackup: http://snapbackup.com/

2.3 Network mirroring software

To mirror over network or locally. This list also not complete, shows only Open Source software:


Unison: http://www.cis.upenn.edu/~bcpierce/unison/index.html

Dirvish: http://www.dirvish.org/

rsync: http://www.samba.org/rsync/


3 Backup scenarios To understand which backup application can be used for which requirement, a short presentation of the different backup scenarios are shown in this chapter. The backup differs a lot depending on the requirements of the service level agreements. Sometimes, it's enough to backup user and application data only. But, if the availability of a service must be guaranteed, a short restore time is required also for the operating system (Recovery Time Objective).

3.1 Data backups

Only user, OS configuration and application data is saved. This backups can be done periodically (scheduled).

3.2 Operating system backups

All operating system relevant data, like boot parameters or kernel relevant setting, are part of this backup type. Those backups can be part of data backups, so you also can schedule them.

Picture 2: Operating system backups

Picture 1: Data backups


3.3 Data restores

Data restore means, the Operating system has already been restored. If the backup contains operating system data, it can only be restored, after the operating system itself has been restored using disaster recovery software, see next chapter.

3.4 Operating system or disaster recoveries

If you have to recover a crashed server, for example loss of all data on operating system disk or hardware damage, you will have to follow this scenario. The procedure to recover such a server is usually divided in several steps:

1. If needed, installation of new hardware 2. Installation of a mini operating system 3. Recovering of operating system relevant data 4. Recovering of user and application data

Picture 3: Data restores

Picture 4: Operating system or disaster recoveries


4 BackupPC

BackupPC is a high-performance, enterprise-grade system for backing up Linux, Windows PC's and laptops to a server's disk. BackupPC is highly configurable and easy to install and maintain. It can be used for daily, weekly or monthly periodic backups. Because the costs of disks and raid systems, it is now practical and cost effective to backup servers directly onto local storage on a backup server. But, if you want to save your data for a long time, you should plan to backup these data to tapes. BackupPC provides you a very reliable, flexible backup solution, if you don't need to backup the data on tapes. If you need to backup the saved data on tape you have a lot of choices, if you want to use OpenSource software.

Category Data backups

Tools used rsync, samba, ssh, nfs or tar

Gui Web based (Apache / perl)

Requirements Apache, Perl, rsnyc, samba, tar, gzip, bzip2, ...

Schedule able Yes, internal

Configuration /etc/BackupPC, or Webgui

Picture 5: BackupPC, exemplary


4.1 Features

A powerful web (HTTP/CGI) user interface allows administrators to view log files, configuration, current status and allows users to initiate and cancel backups, browse and restore files from backups

Different backup mechanism are available (tar, scp, rsync, ...) Incremental backups possible A clever pooling scheme minimizes disk storage and disk I/O. Identical files across multiple backups of

the same or different PCs are stored only once resulting in substantial savings in disk storage and disk I/O

Optional compression support further reducing disk storage. Since only new files (not already pooled) need to be compressed, there is only a modest impact on CPU time

Supports mobile environments where laptops are only intermittently connected to the network and have dynamic IP addresses (DHCP)

Flexible configuration parameters allow multiple backups to be performed in parallel, specification of which shares to backup, which directories to backup or not backup, various schedules for full and incremental backups, schedules for email reminders to users and so on. Configuration parameters can be set system-wide or also on a per-PC basis

Users are sent periodic email reminders if their PC has not recently been backed up. Email content, timing and policies are configurable

Tested on Linux, Freenix and Solaris hosts and Linux, Win95, Win98, Win2000, WinXP clients. Detailed documentation

4.2 Advantages

No client-side software is needed. The standard smb protocol is used to extract backup data on Windows clients. On Linux clients, tar over ssh/rsh/nfs is used to backup the data.

Easy to use web interface Good backup status informations in the web interface A full set of restore options is supported, including direct restore (via smbclient, tar, or rsync/rsyncd) or

downloading a zip or tar file

4.3 Disadvantages

No tape backup is possible Setup of UNIX clients needs UNIX and SSH knowledge Backup storage cannot be on different file systems, because of using hard links Uses quite a lot of CPU resources (rsync)

4.4 Backup

Usually backups are executed in specified time slots, but, if a server was not reachable for a longer time period, the backup is started immediately after BackupPC recognizes the client in the network. Using BackupPC, you do not schedule the backup at a specified time, you can define a time slot, when the backup should be usually done. Following variables control the backup time slots:

$Conf{WakeupSchedule}: In which time period should be the backup started? Can be defined generally or by individual clients.

$Conf{BlackoutPeriods}: What time of day without a normal backup. Normally defined generally, but you can define this also for individual clients.


Status of backups can be reviewed in the web interface:

It's also possible to start backups manually in the web interface. Just select the client and click on the corresponding backup button (Start Incr Backup or Start Full Backup), see Picture 7 next.

Picture 6: Overview of backups in BackupPC webinterface


4.5 Recovery

The restore is also quite easy, like the backup. Everything can be done in the web interface.

Select date of the backup to restore, just click on the Backup# link to select it:

Select data (files and folders) to restore:

Picture 7: Available backup for restore in BackupPC webinterface

Picture 8: Select files and folder to restore in BackupPC


Restore it:

For example a resulting Tar archive looks like this, tar tf ...:

tar tf restore.gtar ./apache2/ ./apache2/conf.d/ ./apache2/conf.d/inst_server.conf.in

Picture 9: Restore options in BackupPC


5 Bacula

Bacula provides the system administrator with a robust, well documented and seriously maintained backup solution comparable to enterprise backup frameworks. The backup catalog is stored in a Database. Bacula is a set of programs which allow the system administrator to manage backup, recover, and verify backup sets across a network of computers of different kinds. Bacula can also run entirely upon a single computer and can backup to various types of media, including tape and disk. In technical terms, it is a network Client/Server based backup program. Bacula is quite easy to use and efficient. For instance by offering many advanced storage management features that make it easy to find and recover lost or damaged files. Due to its modular design, Bacula is scalable from small single computer systems to systems composed of hundreds of computers located over a large network.


Tools used Programm Language C++

Gui QT4 Gui, console based Gui

Requirements MySQL or Postgress DB, mtx for librarys

Schedule able Internal scheduler for automatic and simultaneous job execution

Configuration Internal configuration files

Picture 10: Bacula, exemplary


5.1 Features

A central server and catalog with distributed backup All components communicate via the network and are deployed separately. Internal scheduler for automatic and simultaneous job execution with priorities. Interactive restore of one or more files from:

current backup prior backup of time and date list of files/directories to restore restore by JobId ...

Simple administration with consoles (command line, GUI, and web) Labeled Volumes, to prevent accidental overwriting Support for ANSI / IBM labels Machine independent Volume data format - extensible Support for Unicode on Win32; UTF-8 on Unix Python interpreter for user event (job start, end, ...) scripting Rescue CDROM for bare metal recovery. Hardware Features

Backups can span multiple volumes Multiple backups (jobs, clients, OSes) per volume Supports most tape drives with configurable Device resources Support for multiple drive autochangers (libraries) Supports tape barcode readers Extensive Pool and Volume library management Rapid restoration of individual files (one user reported 4 to 6 hours with tar and 3 to 4 minutes with Bacula!)

Security Features Daemon authorization with CRAM-MD5 Director and Storage daemon can be run non-root MD5, SHA1, ... signatures for each file CRC checksum for each Volume block Restricted consoles and tray-monitors Communications (TLS) encryption Data (PKI) encryption Tripwire like intrusion detection (Verify)

5.2 Advantages

very good support of platforms, operating systems and hardware functionality comparable to enterprise backup solutions robust easy to use excellent documentation no license costs

5.3 Disadvantages

initial configuration not easy

5.4 Backup

scheduler for automatic and simultaneous job execution


5.5 Recovery

fast recovery possible through the GUI and informations from the catalog For more detailed information about Bacula, please consult the Bacula documentation of Roman Gchter on http://www.trivadis.com/de/know-how-community/download-area.html

Picture 11: Bacula scheduler in action


6 Mondorescue

Mondorescue is a disaster recovery solution. It supports Linux (i386, x86_64, ia64) and FreeBSD (i386). It's packaged for multiple distributions (RedHat, RHEL, SuSE, SLES, Mandriva, Debian, Gentoo). It supports tapes, disks, network and CD/DVD as backup media, multiple filesystems, LVM, software and hardware Raid.

Category Baremetal backups (Disaster)

Tools used mkisofs, cdrecord, syslinux, gzip, bzip2, ...

Gui ncurses based gui (command line)

Requirements CD writing tools, syslinux, mindi, gzip, bzip2, ...

Schedule able Yes, via cron

Configuration none

Picture 12: Mondorescue, exemplary


6.1 Features

Automatic system rescue backup through crontab The images can be created directly on running servers The backup can be written directly to CD, DVD, local disk or network drive Created boot image uses the same kernel as the original system, so you shouldn't have problems with

drivers Interactive restore mode, this is very useful for restores on different systems Multiple Linux distributions supported

6.2 Advantages

Very easy to handle backup procedure Could be used to clone servers Differential backups are possible

6.3 Disadvantages

Sometimes, it does not properly restore without using interactive mode, if you have complex disk configuration like LVM or software RAID setups

Not all messages a are coherent Restore is not that simple like a backup

6.4 Backup

To backup, you can choose between two possibilities:

1. Interactive backup with a ncurses based gui (only in console!) 2. Command line, you must enter all needed options as parameters in the command line!

Very important: To make sure, the restore is working fine, you must test it, a wrong backup parameter can make the restore unusable!


6.4.1 ............................................................................................................................ Interactive backup

For an interactive backup, just type mondoarchive:

Backup command, mondoarchive ...:

mondoarchive Initializing... See /var/log/mondoarchive.log for details of backup run. Checking sanity of your Linux distribution /sbin/mkfs.vfat Filesystem 1048576-blocks Used Available Capacity Mounted on /dev/sda1 90036 4577 80886 6% / Done. Execution run ended; result=1 Type 'less /var/log/mondoarchive.log' to see the output log

Following steps and questions will occur during interactive backup:

Welcome screen, choose the media for the backup:

Where to store the ISO image?

Which compression level?

What's the maximum size of DVD or CDROM?

What name prefix for the backup archive?

What's should be included in backup?

What should be excluded from backup?

Should the written data be verified?

Picture 13: Mondorescue backup media options


Execution?

Floppy disk creation always fails, but you can disable the creation using -F option?

Backup finished!

Picture 14: Mondorescue, catalog Picture 15: Mondorescue, boot and data disk

Picture 16: Mondorescue, filesystem backup Picture 17: Mondorescue, filesystem backup progress


6.4.2 ............................................................................................................................ Non interactive backup

To start the non interactive backup, you must only execute one command. Depending the options you have given, the backup will be done direct to CDROM, DVD, NFS share or local disk. mondoarchive creates in all cases a bootable Disk, which can be booted for restore action. For further details about using mondoarchive, please refer to the manual pages.

Backup command, mondoarchive ...:

mondoarchive -O -p ubuntu-t61 -i -N -E /backup -d /backup/ -s 4000m -F -G -l GRUB Initializing... See /var/log/mondoarchive.log for details of backup run. Checking sanity of your Linux distribution Disk /dev/dm-0 doesn't contain a valid partition table Disk /dev/dm-1 doesn't contain a valid partition table Disk /dev/dm-2 doesn't contain a valid partition table Disk /dev/dm-3 doesn't contain a valid partition table Disk /dev/dm-4 doesn't contain a valid partition table Disk /dev/dm-5 doesn't contain a valid partition table Disk /dev/dm-6 doesn't contain a valid partition table Done. BusyBox's sources are available from http://www.busybox.net Making catalog of files to be backed up ---evalcall---1--- Making catalog of / ... ---evalcall---E--- Call to mkisofs to make ISO (ISO #1) ...OK Done. Done. Writing boot+data floppy images to disk No Imgs ---promptpopup---1--- No regular Boot+data floppies were created due of space constraints. However, you can burn /var/cache/mindi/mondorescue.iso to a CD and boot from that. ---promptpopup---Q--- [OK] --- --> Backup and/or verify ran to completion. However, errors did occur. /var/cache/mindi/mondorescue.iso, a boot/utility CD, is available if you want it Data archived OK. See /var/log/mondoarchive.log for details of backup run.

6.5 Recovery

Very Important: You must take care about the following criteria's.

If you have LVM partitions, the nuke (full automatic) restore does not work properly! You need to partition the first hard disk manually.

After partitioning, you need to reboot the server, before you can continue with the restore process. To do so, you need to make a configuration save of the hard disk. Then you have to restore the server using mondo. You must always use interactive mode to restore such a server.

Additionally during interactive restore mode, you must enter the configurations for /boot and swap partitions. Just enter /boot without any size value, for the swap partition you must enter in the mount point and also for the file system type setting swap.

After this you can restore the server. If you will be asked for erasing the disk, enter No to keep the disk partitions.

On Ubuntu installations, you must edit the /etc/fstab and the grub configuration files to correct the disk label information for all file systems. After the restore the UID's of the file systems are different.


7 System rescue CD

SystemRescueCd is a Linux (Gentoo) system on a bootable CD-ROM which contains tools to recover or repair your system. It aims to provide an easy way to carry out admin tasks on your computer, such as creating and editing the partitions of the hard disk. It contains a lot of system utilities (parted, partimage, fstools, ...) and basic tools (editors, midnight commander, network tools). It is very easy to use: Just boot the CDROM. The kernel supports most of the important file systems (ext2/ext3, reiserfs, reiser4, xfs, jfs, vfat, ntfs, iso9660), as well as network filesystems (samba and nfs).

Category Recovery CD

Tools used Gentoo Linux based bootable CD

Gui X11 is available

Requirements CD burner

Schedule able -

Configuration none

Picture 18: System rescue CD, exemplary


7.1 Features

Boot able recovery environment Includes all necessary tools to recover or repair a server Also usable for Windows repair actions Includes graphical tools like gparted, browser, ... From version 1.0 on, chroot is now possible on 64bit servers

7.2 Advantages

Very flexible universal boot CDROM X11 window based applications PXE (network based booting via DHCP and TFTP server) network boot possible for versions above or

equal 1.0 Supports a lot of hardware and file system types

7.3 Disadvantages

Requires UNIX skills, because the most commands are command line based Not bootable over network without significant changes of the ISO image for versions below 1.0


7.4 Usage

Just insert the CDROM into drive and boot from it. When boot prompt is shown, you can switch between different help screens using + + F1, F2, F3, F4, F5, F6 and F7 keys.

It's possible to start X11 window session, to do so, start the wizard command. This lets you choose the type of X11 configuration. To make sure the X11 server starts, choose Xvesa-cfg mode, in this mode you can select the screen resolution. This mode is only available on 32-bit kernels.

Picture 19: System rescue CD boot welcome screen

Picture 20: System rescue CD application examples


8 Installserver based recovery

An installserver is a service which provides the ability to auto install any client over network. Most Linux support the automated installation of operating system. Trivadis recommends an installation through installserver, if this possible. An installserver consists of the following standard network services:

DHCP server TFTP server DNS server NFS, FTP, HTTP or HTTPS server Any automatic installation mechanism, this is usually provided by the Linux distributions:

For Redhat based distributions: Kickstart For SUSE based distributions: Autoyast For Debian based distributions: Autoinstall (FAI)

To recover a server which was confronted with a disaster/failure (no hard disk or no data is accessible), you have to install a new operating system, before you can restore any backup data. This is required, if you didn't perform any disaster backup previously. In case, your installation was already an install server based installation, you can install this system using the same autoyast or kickstart configuration file. An automated recovery of the operating system is also possible, even if you didn't install the failed system from installserver. But, in this case, you must collect the necessary configuration data previously from this system, see Picture 22. Note: This scenario does not include any backup functionality, it only helps to reactivate the operating system as fast as possible. In case of required restore, you must use any backup software.

Category Bare metal backups (Disaster)

Tools used Kickstart, Autoyast, ...

Gui none (Satellite server is web based)

Requirements Linux server, Apache, FTP server, TFTP server, DHCP server, DNS server, ...

Schedule able no

Configuration Kickstart or Autoyast files

Picture 21: Installserver based recover, exemplary


8.1 Features

Fast recovery option, an installation takes about 20 minutes Customizable using scripts

8.2 Advantages

Very fast OS recovering Flexible to restore on different architectures Can be used for training or test center environments

8.3 Disadvantages

Scripting knowledge to make customized installations Sometimes difficult because of PXE (network based booting via DHCP and TFTP server) booting


8.4 Usage

8.4.1 ............................................................................................................................ Collecting configurations

If no kickstart or autoyast profile is available, you must create a new one from a template. For this, you need the configuration of the server, you have to restore. You can collect this data using cfg2html, the Trivadis Installserver documentation or you should have collected the data manually previously to the server crash. The cfg2html package is available from updates or install server.

8.4.2 ............................................................................................................................ Autoyast and kickstart

The next diagram shows an overview for the install server based recovery procedure:

Prerequisites:

Normal daily backups of user data and operating system configurations Periodic snapshots of system configuration, for example with cfg2html Optionally, a script which collects all necessary data to build a autoyast or kickstart file

Backup environment:

Backup server which backups user and OS data daily (Bacula, BackupPC) Configuration database which contains the collected configuration data (Web server)

Installserver:

Trivadis install server or similar Configuration database with all collected autoyast and kickstart files

Picture 22: Installserver based recovery overview


9 Trivadis backup module The Trivadis backup module provides an easy perl-based solution to perform backups from a running server. The script could also be used for full backups, in this case you should backup the server from a bootable CD. The script uses standard

UNIX utilities, except you want to use partimage as the backup solution.

Category Bare metal backups (Disaster)

Tools used partimage or tar

Gui none (command line perl script)

Requirements Perl, partimage, tar, gzip, bzip2

Schedule able yes, via crontab

Configuration Command line options

Picture 23: Trivadis backup module, exemplary


9.1 Features

Automatically creates a copy of all partition tables of all local disks Auto select of all OS related partitions or Logical Volume Groups Backups can be done using partimage or simple tar archives partimage or compressed tar archive creation is possible Stores the disk, LVM and software raid configuration in separate files

9.2 Advantages

Backups can be done onto a remote Server Only standard Linux utilities needed, except you use partimage Just one script to backup the server Backups can be done on running server

9.3 Disadvantages

Script requirements must be resolved manually Restore is only manually possible No incremental or differential backups

9.4 Usage

The backup can be executed using one command. To display a short help, use -h or --help option:

BackupPartimage.pl -h:

Usage: BackupPartimage.pl [ -q ] [ --server ] [ --mbr ] [ --savepath ] [ --vg [ --vg ... ] ] [ --part [ --part ... ] ] [ --remotepath ] [ --type ] [ --all ] [ --onlyconfig ] [ --defaults ] [ --ztype ] -q => quiet mode, no warnings will be printed. --savepath => Where to save backups, default: '/data/backup'? --all => All partition will be saved, if argument was given. --onlyconfig => No tar or partimage backups will be done, only config of LVM, RAIDs and disks will be made. --defaults => shows the script defaults and exits. --ztype => zip format, allowed is bz2, gzip or none for uncompressed backups. Note: If partimage binary, '/usr/sbin/partimage', was not found on system, script switches automatically to tar backups! In case of any problems, try without '-q' option!!


10 rdiff-backup

Using rdiff-backup it is possible to make full and incremental backups, but the same data occurs once only in the backup archive. This means that the space in archive equals the size of the original (previous) data added to the newly changed data on the system.


Tools used rsync, ssh

Gui none (command line python script)

Requirements Python, librsync (dependency during installation of package)


Configuration Command line options

Picture 24: rdiff-backup, exemplary


10.1 Features

Incremental backups Backups (from or) to remote servers Doesn't waste space in the backup archives, the same data appears only once Command-line tool

10.2 Advantages

Restore with the same script possible Saves space, because of creating hard links for equal files

10.3 Disadvantages

Only command line tool available Uses quite a lot of CPU resources (rsync) For incremental backups it's necessary to create hard links, so only one file system is possible for the

archives


10.4 Usage

In order to make remote backups or restores, rdiff-backup must be installed on both servers. The syntax for remote folders is always like follows:

rdiff-backup user@host::/var user@host::/media/wmax1/rdiff/var

Note: Both, source and destination can be on remote servers. All commands are possible over a network archive, if you use the proper syntax.

Backup (full): This example shows the backup command to backup /var into /media/wmax1/rdiff/var folder.

Backup command, rdiff-backup ...:

rdiff-backup --exclude /var/log --exclude /var/tmp -exclude-sockets \ /var /media/wmax1/rdiff/var

Note: If you want to see, what's included in the backup, use v5 and -print-statistics option.

Backup (incremental):

Backup command, rdiff-backup ...:

rdiff-backup --exclude /var/log --exclude /var/tmp -exclude-sockets \ /var /media/wmax1/rdiff/var

Note: The command for incremental backups is the same. The utility checks the destination first for an existing backup, before it starts an incremental backup.

Show available backup (in time):

Backup command, rdiff-backup -l ...:

rdiff-backup -l /media/wmax1/rdiff/var Found 1 increments: increments.2008-03-28T14:16:04+01:00.dir Fri Mar 28 14:16:04 2008 Current mirror: Mon Mar 31 10:31:38 2008


Compare: This example shows the compare between the current system (/var folder) and the backup

archive (/media/wmax1/rdiff/var).

Backup command, rdiff-backup --compare ...:

rdiff-backup --compare /var /media/wmax1/rdiff/var hanged: lib/dhcp/dhclient.leases changed: lib/init.d changed: lib/init.d/daemons ... new: log new: log/Xorg.0.log new: log/Xorg.0.log.old ... deleted: tmp/rpm-tmp.851

This option is quite useful to check the changes between the (different) archives and the actual or given time, see -compare-at-time 1D option. For further information, please consult the man page.

Restore: There are different ways to restore a file or folder from archive. Using rdiff-backup, or just UNIX commands (like cp, scp, ...), if you need the newest backup to restore.

Backup command, rdiff-backup --restore-as-of \ :

rdiff-backup --restore-as-of 1D \ /media/wmax1/rdiff/var/log /var/log

This would restore a backup from the last day into original destination. It's also possible to redirect a restore.

Remove any old backup from archive:

Backup command, rdiff-backup -remove-older-than :

rdiff-backup --remove-older-than 2W /media/wmax1/rdiff/var

This would remove any backup older than 2 weeks. The restore does not create any directory for you. It does not recursive restore directories, if you select files only!


11 rsnapshot

The perl based rsnapshot is very similar to rdiff-backup, the main difference is the used scripting language. Another important difference is that rsnapshot uses a configuration file to automate the backups through crontab.


Tools used rsync, ssh

Gui none (command line perl script)

Requirements Perl, ssh, rsync, optionally logger, du, cp


Configuration One file: /etc/rsnapshot.conf

Picture 25: rsnapshot, exemplary


11.1 Features

Incremental backups Automatic remove of older backups, see interval option in configuration Fully crontab support (It creates a logfile, and works silently) Configuration is done in one file

11.2 Advantages

Very good for automated backups Customizable logger Takes care using USB or external disks, see no_create_root option

11.3 Disadvantages

Not a lot of interactivity Only in command line available Uses quite a lot of CPU resources (rsync) For incremental backups it's necessary to create hard links, so only one file system is possible for the

archives


11.4 Usage

Configuration:

Only, tho most important settings are shown next.

Main and only configuration file of rsnapshot, /etc/rsnapshot.conf:

... ########################### # SNAPSHOT ROOT DIRECTORY # ########################### # All snapshots will be stored under this root directory. # snapshot_root /media/wmax1/bt # If no_create_root is enabled, rsnapshot will not automatically create the # snapshot_root directory. This is particularly useful if you are backing # up to removable media, such as a FireWire or USB drive. # no_create_root 1 ... ######################################### # BACKUP INTERVALS # # Must be unique and in ascending order # # i.e. hourly, daily, weekly, etc. # ######################################### interval hourly 4 interval daily 7 interval weekly 4 #interval monthly 3 ... ############################### ### BACKUP POINTS / SCRIPTS ### ############################### # LOCALHOST #backup /home/ localhost/ backup /etc/ localhost/ # Ubunto test laptop: backup [email protected]:/etc ubuntu

snaphost_root:

This is the backup archive place, all backups will written here. no_create_root:

If the backup archive is on a mountable drive, you can enable this option. If set and the drive is not mounted, no creation of the root is forced, the script aborts.

interval: In this example, four backups will be rotated, if hourly backup was called. Seven backups will be rotated, if daily backup was called. Four backup will be rotated, if weekly backup was called Make sure, you configure the crontab properly:

Corresponding crontab:

0 */6 * * * /usr/bin/rsnapshot hourly 0 1 * * 1-6 /usr/bin/rsnapshot daily 0 1 * * 0 /usr/bin/rsnapshot weekly

backup:

All backups are defined with this directive. If no further option was given in command line, all this backups are executed.


You can test the configuration using rsnapsot configtest.

Backup:

Backup command, rsnapshot ...:

# rsnapshot -v hourly echo 10406 > /var/run/rsnapshot.pid /usr/bin/rm -rf /media/wmax1/bt/hourly.1/ /usr/bin/cp -al /media/wmax1/bt/hourly.0 /media/wmax1/bt/hourly.1 /usr/bin/rsync -ax --delete --numeric-ids --relative --delete-excluded /etc \ /media/wmax1/bt/hourly.0/localhost/ /usr/bin/rsync -ax --delete --numeric-ids --relative --delete-excluded \ --rsh=/usr/bin/ssh [email protected]:/etc \ /media/wmax1/bt/hourly.0/ubuntu touch /media/wmax1/bt/hourly.0/ rm -f /var/run/rsnapshot.pid

Restore: No restore option is actually included in the rsnapshot script. In case of restore, you must do this manually! You can use scp, cp or rsync to restore any file or folder.

Logging: If nothing else is configured, the logfile is in default location /var/log/rsnapshot.

Logfile example, /var/log/rsnapshot:

... [01/Apr/2008:10:55:23] /usr/bin/rsnapshot -v hourly: started [01/Apr/2008:10:55:23] echo 10204 > /var/run/rsnapshot.pid [01/Apr/2008:10:55:23] /usr/bin/cp -al /media/wmax1/bt/hourly.0 /media/wmax1/bt/hourly.1 [01/Apr/2008:10:55:28] /usr/bin/rsync -ax --delete --numeric-ids --relative --delete-excluded /etc /media/wmax1/bt/hourly.0/localhost/ [01/Apr/2008:10:55:28] touch /media/wmax1/bt/hourly.0/ [01/Apr/2008:10:55:28] rm -f /var/run/rsnapshot.pid [01/Apr/2008:10:55:28] /usr/bin/rsnapshot -v hourly: completed successfully [01/Apr/2008:11:05:40] /usr/bin/rsnapshot -v hourly: started [01/Apr/2008:11:05:40] echo 10406 > /var/run/rsnapshot.pid [01/Apr/2008:11:05:40] /usr/bin/rm -rf /media/wmax1/bt/hourly.1/ [01/Apr/2008:11:05:46] /usr/bin/cp -al /media/wmax1/bt/hourly.0 /media/wmax1/bt/hourly.1 [01/Apr/2008:11:05:51] /usr/bin/rsync -ax --delete --numeric-ids --relative --delete-excluded /etc /media/wmax1/bt/hourly.0/localhost/ [01/Apr/2008:11:05:51] /usr/bin/rsync -ax --delete --numeric-ids --relative --delete-excluded --rsh=/usr/bin/ssh [email protected]:/etc /media/wmax1/bt/hourly.0/ubuntu [01/Apr/2008:11:06:11] touch /media/wmax1/bt/hourly.0/ [01/Apr/2008:11:06:11] rm -f /var/run/rsnapshot.pid [01/Apr/2008:11:06:11] /usr/bin/rsnapshot -v hourly: completed successfully


12 Conclusion Depending on what kind of information/data needs to be backup, Open Source softwares offer serious and reliable alternatives to closed-source products. If you need enterprise ready backup software, Bacula appears to be the most serious candidate. Trivadis did a few Bacula installations on customer sites with very good feedback. However if no backup to tape is required, BackupPC can help a lot. In this case the backup server strategy will be followed. Trivadis uses BackupPC as a part of its backup strategy since three years and advices this solution to save all UNIX based clients with less than 100GB data. rsnapshot or rdiff-backup can also be considered if only a few servers need to be backed up. Because both of these tools use rsync for synchronization, they are quite reliable and proved it, in the practice. Also for disaster/recover purposes, Open Source provides strong backup recovery solutions. We recommend SystemRescueCD, mondoarchive or partimage which allow to design strong and reliable backup concepts. If you have to recover a server, SystemRescueCD can be very flexible and is used by Trivadis since many years.

Bacula BackupPC mondorescue rdiff-backup rsnapshot partimage System-RescueCD

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OpenSource backup tools comparision

ReliabilityUsabilityDisaster backupsData backupsEnterprise

Picture 1: OpenSource software comparision chart

backup recovery oss

Documents

cobian backup

cedar backup

data backup

software list

network backup server

range of software

disaster opensource

simple software applications