Difference between revisions of "Full system backup with rsync"

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m (With a single command: replaced "$HOME/.gvfs" with "/home/*/.gvfs" because apparently it doesn't work any better than "~/" either)
(Include "see also" for Scheuref's snapshot rsync backup scripts)
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[[Category:System recovery]]
 
[[Category:System recovery]]
 
[[cs:Full System Backup with rsync]]
 
[[cs:Full System Backup with rsync]]
This [[rsync]] script allows creating a full backup copy across filesystems. It is setup so that the copy includes intact booting capabilities, optionally excluding selected files.
+
{{Article summary start}}
 +
{{Article summary text|Instructions on backing up the root tree, creating a bootable copy of your system, or for transferring your system to a new drive or partition.}}
 +
{{Article summary heading|Related}}
 +
{{Article summary wiki|Backup Programs}}
 +
{{Article summary wiki|rsync}}
 +
{{Article summary end}}
  
The approach has benefits over omitting system files by just copying personal data; if the system becomes corrupted in the main partition, overcoming the problem means booting into the backup as opposed to identifying and reinstalling affected programs.
+
This article is about using [[rsync]] to transfer a copy of your "/" tree, excluding a few select folders. This approach is considered to be better than [[disk cloning]] with {{ic|dd}} since it allows for a different size, partition table and filesystem to be used, and better than copying with {{ic|cp -a}} as well, because it allows greater control over file permissions, attributes, Access Control Lists (ACLs) and extended attributes. [http://www.bestbits.at/acl/about.html]
  
Instructions were converted from [http://bbs.archlinux.org/viewtopic.php?id=83071 this forum post].
+
Either method will work even while the system is running. Since it's going to take a while, you may freely browse the web during this time. Worst case scenario you won't get the same opened tabs when you restore the backup (or boot from it) because they weren't saved. Not a big deal.
  
==With a single command==
+
== With a single command ==
 
+
This operation can be done while the system is running. Since it's going to take a while, you may freely browse the web during this time. Worst case scenario you won't get the same opened tabs when you restore the backup (or boot from it) because they weren't saved. Not a big deal.
+
  
 
As root, run:
 
As root, run:
  
{{Warning|If you plan on backing up your system somewhere other than /mnt or /media, don't forget to add it to the list, to avoid an infinite loop.}}
+
# rsync -aAXv /* /path/to/backup/folder --exclude={/dev/*,/proc/*,/sys/*,/tmp/*,/run/*,/mnt/*,/media/*,/lost+found}
 +
For information on why these folders were excluded, read the next section.
  
# rsync -av /* /media/Backup/backup --exclude={/dev/*,/proc/*,/sys/*,/tmp/*,/run/*,/mnt/*,/media/*,/lost+found,/home/*/.gvfs}
+
{{Note|If you are heavy user of '''hardlinks''', you might consider using additionally '''{{ic|-H}}''' {{ic|rsync}}'s option, which by default is turned off as memory expensive during rsync run, but nowadays it should be no problem on most of modern machines. There are a lot of hard links below the /usr folder which save disk space.}}
  
{{Note|The contents of {{ic|/dev}}, {{ic|/proc}}, {{ic|/sys}}, {{ic|/tmp}}, {{ic|/run}} were excluded because they are populated at boot (while the folders themselves are ''not'' created), {{ic|/lost+found}} is filesystem-specific, and {{ic|/home/*/.gvfs}} should be added too, so that it won't complain at the end that "some files/attrs were not transferred".}}
+
{{Note|If you plan on backing up your system somewhere other than {{ic|/mnt}} or {{ic|/media}}, don't forget to add it to the list, to avoid an infinite loop.  Also, if there are any bind mounts in the system they should be excluded as well, as not to copy the bind mounted contents twice.  The example below is a good place to start and excludes all the necessary directories that are typically common to all users of Arch Linux.  Your system may have additional areas which you may also want to exclude.  Use the {{ic|mount}} command to list system mounts for additional insight on what to exclude.}}
  
{{Note|Additionally, you may also want to skip {{ic|/home/*/.thumbnails/*}}, {{ic|/home/*/.mozilla/firefox/*.default/Cache/*}} and {{ic|/home/*/.cache/chromium/*}}}}
+
{{Note|You may want to add rsync's '''{{ic|--delete}}''' option if you are running this multiple times to the same backup folder}}
  
==With a list==
+
== Using a script ==
For this method, two files are needed: the backup script and a file stating which files to include/exclude from the backup source.
+
  
===Backup script===
+
Same as in the above method, the system files are transferred in archive mode, ensuring that symbolic links, devices, permissions and ownerships, among other file attributes are preserved, while excluding files that match the patterns from the {{ic|--exclude}} string. On top of that, it shows at the end how much time it took, and it also writes a blank file stating when the backup was created. To learn more about what this script does, read {{ic|man rsync}} and {{ic|man date}}.
The script is very simple; it rsyncs in archive mode, ensuring that symbolic links, devices, permissions and ownerships, among other file attributes are preserved, while excluding files that match the patterns from the include/exclude list.
+
  
Save it as {{ic|backup.sh}} and make it executable:
+
{{Note|Again, if you plan on backing up your system somewhere other than {{ic|/mnt}} or {{ic|/media}}, don't forget to add it to the list, to avoid an infinite loop.}}
{{hc|$ nano ~/backup.sh|2=
+
#!/bin/sh
+
  
sudo sh -c "
+
{{Note|You may want to add rsync's '''{{ic|--delete}}''' option if you are running this multiple times to the same backup folder}}
    rsync -av --delete-excluded --exclude-from=backup.lst / $1;
+
    date > $1/BACKUP
+
"
+
}}
+
  
$ chmod +x ~/backup.sh
+
{{hc|$ cd ~/Scripts
 +
$ nano backup.sh|<nowiki>
 +
#!/bin/sh
  
'''Backup source:''' {{ic|/}} — In this case it performs a backup of the whole root.
+
if [ $# -lt 1 ]; then
 +
    echo "No destination defined. Usage: $0 destination" >&2
 +
    exit 1
 +
elif [ $# -gt 1 ]; then
 +
    echo "Too many arguments. Usage: $0 destination" >&2
 +
    exit 1
 +
elif [ ! -d "$1" ]; then
 +
  echo "Invalid path: $1" >&2
 +
  exit 1
 +
elif [ ! -w "$1" ]; then
 +
  echo "Directory not writable: $1" >&2
 +
  exit 1
 +
fi
  
'''Backup destination:''' {{ic|$1}} — Substitutes the backup destination later on.
+
case "$1" in
 +
  "/mnt") ;;
 +
  "/mnt/"*) ;;
 +
  "/media") ;;
 +
  "/media/"*) ;;
 +
  *) echo "Destination not allowed." >&2
 +
    exit 1
 +
    ;;
 +
esac
  
'''Exclude list:''' {{ic|<nowiki>--exclude-from=backup.lst</nowiki>}} — This example uses a file called ''backup.lst''.
+
START=$(date +%s)
 +
rsync -aAXv /* $1 --exclude /dev/* --exclude /proc/* --exclude /sys/* --exclude /tmp/* --exclude /run/* --exclude /mnt/* --exclude /media/* --exclude /lost+found --exclude /var/lib/pacman/sync/*
 +
FINISH=$(date +%s)
 +
echo "total time: $(( ($FINISH-$START) / 60 )) minutes, $(( ($FINISH-$START) % 60 )) seconds"
  
===Exclude list===
+
touch $1/"Backup from $(date '+%A, %d %B %Y, %T')"</nowiki>}}
As deciding which files should populate this list can be difficult, here's a typical example of files that do not need to be backed up.
+
  
Save the following as {{ic|backup.lst}}:
+
$ chmod +x backup.sh
  
{{hc|$ nano ~/backup.lst|
+
{{Note|The contents of {{ic|/dev}}, {{ic|/proc}}, {{ic|/sys}}, {{ic|/tmp}}, {{ic|/run}} were excluded because they are populated at boot (while the folders themselves are ''not'' created), {{ic|/lost+found}} is filesystem-specific. For Arch Linux, {{ic|/var/lib/pacman/sync/*}} can also be excluded. This can save a lot of time on every backup since the directory contains many small files that tend to change quite often. These are description files for every package from the repositories and can be re-generated with {{ic|pacman -Syu}}. Additionally, you may also want to skip {{ic|/home/*/.thumbnails/*}}, {{ic|/home/*/.mozilla/firefox/*.default/Cache/*}} and {{ic|/home/*/.cache/chromium/*}}.}}
# Include
+
  
''# Commented out. See bellow.''
+
Backing up is easy.
  
 +
While the system is running, open up a terminal and run (as root):
  
# Exclude
+
# /home/user/Scripts/backup.sh /some/destination
- /dev/*
+
(replace user with username since you created the directory as user in the user's home directory)
- /run/*
+
- /proc/*
+
- /sys/*
+
- /tmp/*
+
- lost+found/
+
- /media/*
+
- /mnt/*
+
}}
+
  
{{Warning|don't forget to also exclude the mounted directory where you'll put the backup to avoid an infinite loop. You can use some folder in /media or /mnt, since they're already on the list.}}
+
You can also replace both {{ic|$1}} instances from the script with the actual destination path, move it to one of the folders from {{ic|echo $PATH}}, and then simply run (as root):
  
;Exclude: Content in system directories; {{ic|/dev}}, {{ic|/proc}}, {{ic|/sys}} and {{ic|/tmp}} are excluded because they are created by the system at runtime, while the directories themselves need to be preserved since they are ''not'' regenerated at boot. Lastly, all {{ic|lost+found}} instances are skipped since they are partition-specific. For Archlinux {{ic|/var/lib/pacman/sync/*}} can also be excluded. This can save a lot of time on every backup since the directory contains many small files that tend to change quite often. These are description files for every package from the repositories. These files can be regenerated with {{ic|pacman -Syu}}.
+
# backup.sh
  
;Include: See the example at the bottom of this article if you explicitly want to keep something from the user folder or /media ''(although you could simply copy them after rsync is done, so this section is a bit redundant)''. Note that specifying every desired file or directory in {{ic|Include}} is not needed; this section only acts as a filter for statements in {{ic|Exclude}}.
+
== Boot requirements ==
  
===Backing up===
+
Having a bootable backup can be useful in case the filesystem becomes corrupt or if an update breaks the system. The backup can also be used as a test bed for updates, with the [testing] repo enabled, etc. If you transferred the system to a different partition or drive and you want to boot it, the process is as simple as updating the backup's {{ic|/etc/fstab}} and your bootloader's configuration file.
While the system is running, open a terminal and run (as root):
+
# ~/backup.sh /media/backup
+
  
{{Note|Substitute {{ic|/media/backup}} as appropriate.}}
+
=== Update the fstab ===
  
==Boot requirements==
+
Without rebooting, edit the backup's [[fstab]] to reflect the changes:
 +
{{hc|# nano /path/to/backup/etc/fstab|2=
 +
tmpfs        /tmp          tmpfs    nodev,nosuid            0  0
  
If you transferred the system to a different partition or drive and you want to boot it, the process is as simple as updating the backup's {{ic|/etc/fstab}} and your bootloader's configuration file (e.g. {{ic|/boot/grub/menu.lst}}). But if you plan on replacing the current install (or replacing the drive) and you know that you will no longer have a bootloader, you will also have to (''re'')install one.
+
<font color=#888888><i>/dev/sda1    /boot        ext2      defaults                0  2
 
+
Here's how you can find out the device name or [[UUID]] of a certain partition:
+
 
+
# fdisk -l
+
# blkid
+
 
+
===Update the fstab===
+
Edit the backup's [[fstab]] to reflect the changes:
+
{{hc|# nano /media/backup/etc/fstab|
+
tmpfs        /tmp          tmpfs    nodev,nosuid,noexec      0  0
+
 
+
<i>/dev/sda1    /boot        ext2      defaults                0  2
+
 
/dev/sda5    none          swap      defaults                0  0
 
/dev/sda5    none          swap      defaults                0  0
 
/dev/sda6    /            ext4      defaults                0  1
 
/dev/sda6    /            ext4      defaults                0  1
/dev/sda7    /home        ext4      defaults                0  2</i>
+
/dev/sda7    /home        ext4      defaults                0  2</i></font>}}
}}
+
  
 
Because rsync has performed a recursive copy of the ''entire'' root filesystem, all of the {{ic|sda}} mountpoints are problematic and booting the backup will fail. In this example, all of the offending entries are replaced with a single one:
 
Because rsync has performed a recursive copy of the ''entire'' root filesystem, all of the {{ic|sda}} mountpoints are problematic and booting the backup will fail. In this example, all of the offending entries are replaced with a single one:
{{hc|# nano /media/backup/etc/fstab|
 
tmpfs        /tmp          tmpfs    nodev,nosuid,noexec      0  0
 
  
/dev/'''sdb1'''    /            ext4      defaults                0  1
+
{{hc|# nano /path/to/backup/etc/fstab|
}}
+
tmpfs        /tmp          tmpfs    nodev,nosuid            0  0
 +
 
 +
/dev/'''sdb1'''    /            ext4      defaults                0  1}}
  
 
Remember to use the proper device name and filesystem type.
 
Remember to use the proper device name and filesystem type.
  
===Update the bootloader's configuration file===
+
=== Update the bootloader's configuration file ===
  
 
This section assumes that you backed up the system to another drive or partition, that your current bootloader is working fine, and that you want to boot from the backup as well.
 
This section assumes that you backed up the system to another drive or partition, that your current bootloader is working fine, and that you want to boot from the backup as well.
  
{{Tip|Instead of updating the configuration file, you can also temporarily edit the menu during boot. When the menu shows up, press ''e'' (for GRUB) or the ''Tab'' key (Syslinux) and change the relevant entries. To boot, press ''b'' (GRUB) or ''Enter'' (Syslinux).}}
+
For [[Syslinux]], all you need to do is duplicate the current entry, except pointing to a different drive or partition:
  
{{Note|You should take this opportunity to consult their wiki pages to learn which ones start counting drives/partitions from zero and which ones do not. For example, GRUB Legacy sees {{ic|(hd0,0)}} as the first partition of the first drive. Syslinux will see it as {{ic|h0 1}}.}}
+
{{Tip|Instead of editing {{ic|syslinux.cfg}}, you can also temporarily edit the menu during boot. When the menu shows up, press the {{ic|Tab}} key and change the relevant entries. Partitions are counted from one, drives are counted from zero.}}
 
+
All you need to do is duplicate the current entry, except pointing to a different drive or partition.
+
 
+
For [[GRUB Legacy]]:
+
 
+
# nano /boot/grub/menu.lst
+
 
+
For [[Syslinux]]:
+
  
 
  # nano /boot/syslinux/syslinux.cfg
 
  # nano /boot/syslinux/syslinux.cfg
  
For [[GRUB2]], it's recommended that you automatically re-generate a .cfg:
+
For [[GRUB]], it's recommended that you automatically re-generate the {{ic|grub.cfg}} file:
  
 +
# pacman -S os-prober
 
  # grub-mkconfig -o /boot/grub/grub.cfg
 
  # grub-mkconfig -o /boot/grub/grub.cfg
  
===(Re)install the bootloader===
+
== See also ==
 
+
This section assumes that the system was backed up on a machine that no longer has a bootloader installed, or a machine that only has Windows on it (e.g. Windows has taken over the MBR after reinstalling it).
+
 
+
{{Box RED|Remember:|Don't forget to set the ''boot'' flag on {{ic|/dev/sda1}} (or whatever partition the boot files are located) using either {{ic|gparted}} or {{ic|cfdisk}}, depending on whichever the LiveCD comes with. Else you may get a ''"Missing operating system. FATAL: INT18: BOOT FAILURE"'' message.}}
+
 
+
 
+
So, using a "live" Linux distribution and from a [[chroot]] environment ''(this is important)'', run:
+
 
+
{{Box RED|Note:|Use {{ic|/dev/sdx}}, not {{ic|/dev/sdx1}}; you want to install to the MBR.}}
+
 
+
'''GRUB Legacy''':
+
 
+
# grub-install /dev/sda
+
 
+
'''GRUB2''':
+
 
+
# grub-install /dev/sda
+
# grub-mkconfig -o /boot/grub/grub.cfg
+
 
+
'''Syslinux''':
+
 
+
# extlinux --install /boot/syslinux
+
# dd bs=440 conv=notrunc count=1 if=/usr/lib/syslinux/mbr.bin of=/dev/sda
+
  
== External links ==
+
# [http://blog.pointsoftware.ch/index.php/howto-local-and-remote-snapshot-backup-using-rsync-with-hard-links/ Howto – local and remote snapshot backup using rsync with hard links] Includes file deduplication with hard-links, MD5 integrity signature, 'chattr' protection, filter rules, disk quota, retention policy with exponential distribution (backups rotation while saving more recent backups than older)
A sample implementation can be found here:
+
* https://bitbucket.org/wooptoo/bin/raw/tip/bak
+
* https://bitbucket.org/wooptoo/bin/raw/tip/bak_list
+

Revision as of 16:56, 15 September 2013

Summary help replacing me
Instructions on backing up the root tree, creating a bootable copy of your system, or for transferring your system to a new drive or partition.
Related
Backup Programs
rsync

This article is about using rsync to transfer a copy of your "/" tree, excluding a few select folders. This approach is considered to be better than disk cloning with dd since it allows for a different size, partition table and filesystem to be used, and better than copying with cp -a as well, because it allows greater control over file permissions, attributes, Access Control Lists (ACLs) and extended attributes. [1]

Either method will work even while the system is running. Since it's going to take a while, you may freely browse the web during this time. Worst case scenario you won't get the same opened tabs when you restore the backup (or boot from it) because they weren't saved. Not a big deal.

With a single command

As root, run:

# rsync -aAXv /* /path/to/backup/folder --exclude={/dev/*,/proc/*,/sys/*,/tmp/*,/run/*,/mnt/*,/media/*,/lost+found}

For information on why these folders were excluded, read the next section.

Note: If you are heavy user of hardlinks, you might consider using additionally -H rsync's option, which by default is turned off as memory expensive during rsync run, but nowadays it should be no problem on most of modern machines. There are a lot of hard links below the /usr folder which save disk space.
Note: If you plan on backing up your system somewhere other than /mnt or /media, don't forget to add it to the list, to avoid an infinite loop. Also, if there are any bind mounts in the system they should be excluded as well, as not to copy the bind mounted contents twice. The example below is a good place to start and excludes all the necessary directories that are typically common to all users of Arch Linux. Your system may have additional areas which you may also want to exclude. Use the mount command to list system mounts for additional insight on what to exclude.
Note: You may want to add rsync's --delete option if you are running this multiple times to the same backup folder

Using a script

Same as in the above method, the system files are transferred in archive mode, ensuring that symbolic links, devices, permissions and ownerships, among other file attributes are preserved, while excluding files that match the patterns from the --exclude string. On top of that, it shows at the end how much time it took, and it also writes a blank file stating when the backup was created. To learn more about what this script does, read man rsync and man date.

Note: Again, if you plan on backing up your system somewhere other than /mnt or /media, don't forget to add it to the list, to avoid an infinite loop.
Note: You may want to add rsync's --delete option if you are running this multiple times to the same backup folder
$ cd ~/Scripts
$ nano backup.sh
#!/bin/sh

if [ $# -lt 1 ]; then 
    echo "No destination defined. Usage: $0 destination" >&2
    exit 1
elif [ $# -gt 1 ]; then
    echo "Too many arguments. Usage: $0 destination" >&2
    exit 1
elif [ ! -d "$1" ]; then
   echo "Invalid path: $1" >&2
   exit 1
elif [ ! -w "$1" ]; then
   echo "Directory not writable: $1" >&2
   exit 1
fi

case "$1" in
  "/mnt") ;;
  "/mnt/"*) ;;
  "/media") ;;
  "/media/"*) ;;
  *) echo "Destination not allowed." >&2 
     exit 1 
     ;;
esac

START=$(date +%s)
rsync -aAXv /* $1 --exclude /dev/* --exclude /proc/* --exclude /sys/* --exclude /tmp/* --exclude /run/* --exclude /mnt/* --exclude /media/* --exclude /lost+found --exclude /var/lib/pacman/sync/*
FINISH=$(date +%s)
echo "total time: $(( ($FINISH-$START) / 60 )) minutes, $(( ($FINISH-$START) % 60 )) seconds"

touch $1/"Backup from $(date '+%A, %d %B %Y, %T')"
$ chmod +x backup.sh
Note: The contents of /dev, /proc, /sys, /tmp, /run were excluded because they are populated at boot (while the folders themselves are not created), /lost+found is filesystem-specific. For Arch Linux, /var/lib/pacman/sync/* can also be excluded. This can save a lot of time on every backup since the directory contains many small files that tend to change quite often. These are description files for every package from the repositories and can be re-generated with pacman -Syu. Additionally, you may also want to skip /home/*/.thumbnails/*, /home/*/.mozilla/firefox/*.default/Cache/* and /home/*/.cache/chromium/*.

Backing up is easy.

While the system is running, open up a terminal and run (as root):

# /home/user/Scripts/backup.sh /some/destination

(replace user with username since you created the directory as user in the user's home directory)

You can also replace both $1 instances from the script with the actual destination path, move it to one of the folders from echo $PATH, and then simply run (as root):

# backup.sh

Boot requirements

Having a bootable backup can be useful in case the filesystem becomes corrupt or if an update breaks the system. The backup can also be used as a test bed for updates, with the [testing] repo enabled, etc. If you transferred the system to a different partition or drive and you want to boot it, the process is as simple as updating the backup's /etc/fstab and your bootloader's configuration file.

Update the fstab

Without rebooting, edit the backup's fstab to reflect the changes:

# nano /path/to/backup/etc/fstab
tmpfs        /tmp          tmpfs     nodev,nosuid             0   0

/dev/sda1    /boot         ext2      defaults                 0   2
/dev/sda5    none          swap      defaults                 0   0
/dev/sda6    /             ext4      defaults                 0   1
/dev/sda7    /home         ext4      defaults                 0   2

Because rsync has performed a recursive copy of the entire root filesystem, all of the sda mountpoints are problematic and booting the backup will fail. In this example, all of the offending entries are replaced with a single one:

# nano /path/to/backup/etc/fstab
tmpfs        /tmp          tmpfs     nodev,nosuid             0   0

/dev/sdb1    /             ext4      defaults                 0   1

Remember to use the proper device name and filesystem type.

Update the bootloader's configuration file

This section assumes that you backed up the system to another drive or partition, that your current bootloader is working fine, and that you want to boot from the backup as well.

For Syslinux, all you need to do is duplicate the current entry, except pointing to a different drive or partition:

Tip: Instead of editing syslinux.cfg, you can also temporarily edit the menu during boot. When the menu shows up, press the Tab key and change the relevant entries. Partitions are counted from one, drives are counted from zero.
# nano /boot/syslinux/syslinux.cfg

For GRUB, it's recommended that you automatically re-generate the grub.cfg file:

# pacman -S os-prober
# grub-mkconfig -o /boot/grub/grub.cfg

See also

  1. Howto – local and remote snapshot backup using rsync with hard links Includes file deduplication with hard-links, MD5 integrity signature, 'chattr' protection, filter rules, disk quota, retention policy with exponential distribution (backups rotation while saving more recent backups than older)