Ubuntu Manpage: rear - bare metal disaster recovery and system migration tool

NAME

       rear - bare metal disaster recovery and system migration tool

SYNOPSIS

       rear [-h|--help] [-V|--version] [-dsSv] [-D|--debugscripts SET] [-c DIR] [-C CONFIG] [-r KERNEL] [--]
       COMMAND [ARGS...]

DESCRIPTION

Relax-and-Recover (abbreviated ReaR) is the leading Open Source disaster recovery solution. It is a
modular framework with many ready-to-go workflows for common situations.

Relax-and-Recover produces a bootable image. This image can repartition the system. Once that is done it
initiates a restore from backup. Restores to different hardware are possible. Relax-and-Recover can
therefore be used as a migration tool as well.

Currently Relax-and-Recover supports various boot media (incl. ISO, PXE, OBDR tape, USB or eSATA
storage), a variety of network protocols (incl. sftp, ftp, http, nfs, cifs) for storage and backup as
well as a multitude of backup strategies (incl. IBM Tivoli Storage Manager, MircoFocus Data Protector,
Symantec NetBackup, EMC NetWorker, EMC Avamar, FDR/Upstream, NovaStor DC, Rubrik Cloud Data Management
(CDM), Bareos, Bacula, rsync, rbme, Borg). This results in a bootable image that is capable of booting
via PXE, DVD/CD, bootable tape or virtual provisioning.

Relax-and-Recover was designed to be easy to set up, requires no maintenance and is there to assist when
disaster strikes. Its setup-and-forget nature removes any excuses for not having a disaster recovery
solution implemented.

Recovering from disaster is made very straight-forward by a 2-step recovery process so that it can be
executed by operational teams when required. When used interactively (e.g. when used for migrating
systems), menus help make decisions to restore to a new (hardware) environment.

Extending Relax-and-Recover is made possible by its modular framework. Consistent logging and optionally
extended output help understand the concepts behind Relax-and-Recover and help debug during development.

Relax-and-Recover comes with ABSOLUTELY NO WARRANTY; for details see the GNU General Public License at:
http://www.gnu.org/licenses/gpl.html

OPTIONS

   GLOBAL OPTIONS
       -h --help
           usage information

       -c DIR
           alternative config directory; instead of /etc/rear

       -C CONFIG
           additional config file; absolute path or relative to config directory

       -d
           debug mode (run many commands verbosely with debug messages in log file - also sets -v)

       -D
           debugscript mode (log executed commands via 'set -x' - also sets -v and -d)

       --debugscripts SET
           same as -d -v -D but debugscript mode with 'set -SET'

       -r KERNEL
           kernel version to use (by default use running kernel)

       -s
           simulation mode (show what scripts are run without executing them)

       -S
           step-by-step mode (acknowledge each script individually)

       -v
           verbose mode (show messages what ReaR is doing on the terminal)

       -V --version
           version information

   COMMANDS
       checklayout
           check if the disk layout has changed since the last run of mkbackup/mkrescue

       dump
           dump configuration and system information; run this to verify your setup

       format
           format and label USB or tape media to be used with rear; first argument is the USB or tape device to
           use, eg. /dev/sdX or /dev/stX

       help
           print full list of commands and options

       mkbackup
           create rescue media and backup the system (only for internal backup methods)

       mkbackuponly
           backup the system (only for internal backup methods) without creating rescue media

       mkrescue
           create rescue media only

       mountonly
           use ReaR as live media to mount and repair the system

       recover
           recover the system; can be used only when running from the rescue media

       restoreonly
           only restore the backup; can be used only when running from the rescue media

       mkopalpba
           create a pre-boot authentication (PBA) image to boot from TCG Opal 2-compliant self-encrypting disks

       opaladmin
           administrate TCG Opal 2-compliant self-encrypting disks

       validate
           submit validation information

       Use 'rear -v help' for more advanced commands.

BACKGROUND INFORMATION

       The process of bare metal disaster recovery consists of two parts:

       •   Recreate the system layout

       •   Restore the data to the system

       Most backup software solutions are very good at restoring data but do not support recreating the system
       layout. Relax-and-Recover is very good at recreating the system layout but works best when used together
       with supported backup software.

       In this combination Relax-and-Recover recreates the system layout and calls the backup software to
       restore the actual data. Thus there is no unnecessary duplicate data storage and the Relax-and-Recover
       rescue media can be very small.

       For demonstration and special use purposes Relax-and-Recover also includes an internal backup method,
       NETFS, which can be used to create a simple tar.gz archive of the system. For all permanent setups we
       recommend using something more professional for backup, either a traditional backup software (open source
       or commercial) or rsync with hardlink based solutions, e.g. RSYNC BACKUP MADE EASY.

RESCUE IMAGE CONFIGURATION

The OUTPUT variable defines from where our bootable rescue image will be booted and the OUTPUT_URL
variable defines where the rescue image should be send to. Possible OUTPUT settings are:

OUTPUT=RAMDISK
Create only the Relax-and-Recover initramfs.

OUTPUT=ISO
(Default) Create a bootable ISO9660 image on disk as rear-$(hostname).iso

OUTPUT=PXE
Create on a remote PXE/NFS server the required files (such as configuration file, kernel and initrd
image)

OUTPUT=OBDR
Create a bootable OBDR tape (optionally including the backup archive). Specify the OBDR tape device
by using TAPE_DEVICE.

OUTPUT=USB
Create a bootable USB disk.

OUTPUT=RAWDISK
Create a bootable image file named "rear-$(hostname).raw.gz", which

• supports UEFI boot if syslinux/EFI or Grub 2/EFI is installed,

• supports Legacy BIOS boot if syslinux is installed,

• supports UEFI/Legacy BIOS dual boot if syslinux and one of the supported EFI bootloaders are
installed.

When using OUTPUT=ISO, RAMDISK, OBDR, USB, or RAWDISK you should provide the backup target location
through the OUTPUT_URL variable. Possible OUTPUT_URL settings are:

OUTPUT_URL=file://
Write the image to disk. The default is in /var/lib/rear/output/.

OUTPUT_URL=nfs://
Write the image by mounting the target filesystem via NFS.

OUTPUT_URL=cifs://
Write the image by mounting the target filesystem via CIFS.

OUTPUT_URL=fish://
Write the image using lftp and the FISH protocol.

OUTPUT_URL=ftp://
Write the image using lftp and the FTP protocol.

OUTPUT_URL=ftps://
Write the image using lftp and the FTPS protocol.

OUTPUT_URL=hftp://
Write the image using lftp and the HFTP protocol.

OUTPUT_URL=http://
Write the image using lftp and the HTTP (PUT) procotol.

OUTPUT_URL=https://
Write the image using lftp and the HTTPS (PUT) protocol.

OUTPUT_URL=sftp://
Write the image using lftp and the secure FTP (SFTP) protocol.

OUTPUT_URL=rsync://
Write the image using rsync and the RSYNC protocol.

OUTPUT_URL=sshfs://
Write the image using sshfs and the SSH protocol.

OUTPUT_URL=null
Do not copy the rescue image from /var/lib/rear/output/ to a remote output location. OUTPUT_URL=null
is useful when another program (e.g. an external backup program) is used to save the rescue image
from the local system to a remote place, or with BACKUP_URL=iso:///backup when the backup is included
in the rescue image to avoid a (big) copy of the rescue image at a remote output location. In the
latter case the rescue image must be manually saved from the local system to a remote place.
OUTPUT_URL=null is only supported together with BACKUP=NETFS.

If you do not specify OUTPUT_URL variable then by default it will be aligned to what was defined by
variable BACKUP_URL. And, the rescue image will then be copied to the same location as your backup of the
system disk(s).

The ISO_DEFAULT variable defines what default boot option is used on the rescue image. Possible values
are manual, boothd or automatic. Manual will make you boot into the shell directly by default, boothd
will boot to the first disk (default) or automatic will automatically start in recovery mode.

RESCUE IMAGE KERNEL COMMAND LINE OPTIONS

       When booting the rescue image you can edit the kernel command line. There are some Relax-and-Recover
       specific kernel command line options:

       debug
           The rescue system start up scripts in /etc/scripts/system-setup.d/ are run one by one each one after
           pressing 'Enter' and the scripts are run with 'set -x' which prints commands and their arguments as
           they are executed.

       auto_recover or automatic
           Launch 'rear recover' automatically (without automated reboot). Together with 'debug' it runs 'rear
           recover' in debug mode.

       unattended
           Launch 'rear recover' automatically as with 'auto_recover' plus automated reboot after successful
           'rear recover'.

       ip= nm= netdev= gw=
           If IP address plus optionally netmask (default 255.255.255.0), network device (default eth0), and a
           default gateway are specified only that single network device is set up. Example:

           ip=192.168.100.2 nm=255.255.255.0 netdev=eth0 gw=192.168.100.1

       noip
           Skip network devices setup by the rescue system start up scripts (overrides ip= nm= netdev= gw=).

BACKUP SOFTWARE INTEGRATION

Currently Relax-and-Recover supports the following backup methods. There is a distinction between
Relax-and-Recover support for 3rd party backup software and Relax-and-Recover internal backup methods.
The latter also creates a backup of your data while the former will only integrate Relax-and-Recover with
the backup software to restore the data with the help of the backup software without actually creating
backups. This means that for all non-internal backup software you must take care of creating backups
yourself (unless otherwise noted).

Especially the rear mkbackup command can be confusing as it is only useful for the internal backup
methods and has usually no function at all with the other (external) backup methods.

The following backup methods need to be set in Relax-and-Recover with the BACKUP option. As mentioned we
have two types of BACKUP methods - internal and external.

The following BACKUP methods are external of Relax-and-Recover meaning that usually you are responsible
of backups being made:

BACKUP=REQUESTRESTORE
(default) Not really a backup method at all, Relax-and-Recover simply halts the recovery and requests
that somebody will restore the data to the appropriate location (e.g. via SSH). This method works
especially well with an rsync based backup that is pushed back to the backup client.

BACKUP=EXTERNAL
Internal backup method that uses an arbitrary external command to create a backup and restore the
data.

BACKUP=DP
Use Micro Focus Data Protector to restore the data.

BACKUP=FDRUPSTREAM
Use FDR/Upstream to restore the data.

BACKUP=GALAXY
Use CommVault Galaxy 5 to restore the data.

BACKUP=GALAXY7
Use CommVault Galaxy 7 to restore the data.

BACKUP=GALAXY10
Use CommVault Galaxy 10 (or Simpana 10) to restore the data.

BACKUP=NBU
Use Symantec NetBackup to restore the data.

BACKUP=TSM
Use IBM Tivoli Storage Manager to restore the data. The Relax-and-Recover result files (e.g. ISO
image) are also saved into TSM. There is a (currently experimental) first draft implementation that a
TSM backup is created by calling 'dsmc incremental' during 'rear mkbackup'.

BACKUP=NSR
Using EMC NetWorker (Legato) to restore the data.

BACKUP=AVA
Using EMC Avamar to restore the data.

BACKUP=SESAM
Using SEP Sesam to restore the data.

BACKUP=NBKDC
Using NovaStor DC to restore the data.

BACKUP=CDM
Using Rubrik Cloud Data Management (CDM) to restore the data.

BACKUP=RBME
Use Rsync Backup Made Easy (rbme) to restore the data.

BACKUP=BAREOS
Use Open Source backup solution BAREOS (a fork a BACULA) to restore the data.

BACKUP=BACULA
Use Open Source backup solution BACULA to restore the data.

BACKUP=DUPLICITY
Use encrypted bandwidth-efficient backup solution using the rsync algorithm to restore the data.

BACKUP=BORG
Use BorgBackup (short Borg) a deduplicating backup program to restore the data. Executing 'rear
mkbackup' will create a Borg backup, see the section 'ReaR with Borg back end' in the ReaR user-guide
'Scenarios' documentation.

The following BACKUP methods are internal of Relax-and-Recover:

BACKUP=NETFS
Internal backup method which can be used to create a simple backup (tar archive).

BACKUP=RSYNC
Use rsync to restore data.

If your favourite backup software is missing from this list, please submit a patch or ask us to implement
it for you.

When using BACKUP=NETFS you must provide the backup target location through the BACKUP_URL variable.
Possible BACKUP_URL settings are:

BACKUP_URL=file://
To backup to local disk, use BACKUP_URL=file:///directory/path/

BACKUP_URL=nfs://
To backup to NFS disk, use BACKUP_URL=nfs://nfs-server-name/share/path

BACKUP_URL=tape://
To backup to tape device, use BACKUP_URL=tape:///dev/nst0 or alternatively, simply define
TAPE_DEVICE=/dev/nst0

BACKUP_URL=rsync://
When backup method BACKUP=RSYNC is chosen then we need to define a corresponding BACKUP_URL rule:

BACKUP_URL=rsync://[user@]host[:port]/path
BACKUP_URL=rsync://[user@]host[:port]::/path

BACKUP_URL=cifs://
To backup to a Samba share (CIFS), use BACKUP_URL=cifs://cifs-server-name/share/path. To provide
credentials for CIFS mounting use a /etc/rear/cifs credentials file and define
BACKUP_OPTIONS="cred=/etc/rear/cifs" and pass along:

username=_username_
password=_secret password_
domain=_domain_

BACKUP_URL=usb://
To backup to USB storage device, use BACKUP_URL=usb:///dev/disk/by-label/REAR-000 or use a partition
device node or a specific filesystem label. Alternatively, you may specify the partition device using
USB_DEVICE=/dev/disk/by-label/REAR-000 if needed.

If you combine this with OUTPUT=USB you will end up with a bootable USB device.

BACKUP_URL=sshfs://
To backup to a remote server via sshfs (SSH protocol), use
BACKUP_URL=sshfs://user@remote-system.name.org/home/user/backupdir/

It is advisable to add ServerAliveInterval 15 in the /root/.ssh/config file for the remote system
(remote-system.name.org).

BACKUP_URL=iso://
To include the backup within the ISO image. It is important that the BACKUP_URL and OUTPUT_URL
variables are different. E.g.

BACKUP_URL=iso:///backup/
OUTPUT_URL=nfs://server/path/

When using BACKUP=NETFS and BACKUP_PROG=tar there is an option to select BACKUP_TYPE=incremental or
BACKUP_TYPE=differential to let rear make incremental or differential backups until the next full backup
day e.g. via FULLBACKUPDAY="Mon" is reached or when the last full backup is too old after
FULLBACKUP_OUTDATED_DAYS has passed. Incremental or differential backup is currently only known to work
with BACKUP_URL=nfs. Other BACKUP_URL schemes may work but at least BACKUP_URL=usb requires USB_SUFFIX to
be set to work with incremental or differential backup.

SUPPORT FOR SELF-ENCRYPTING DISKS

       Relax-and-Recover supports self-encrypting disks (SEDs) compliant with the TCG Opal 2 specification if
       the sedutil-cli executable is installed.

       Self-encrypting disk support includes

       •   recovery (saving and restoring the system’s SED configuration),

       •   setting up SEDs, including assigning a disk password,

       •   providing a pre-boot authentication (PBA) system to unlock SEDs at boot time.

       To prepare booting from an SED, run rear mkopalpba, then create the rescue system.

       To set up an SED, boot the Relax-and-Recover rescue system and run rear opaladmin setupERASE DEVICE
       (DEVICE being the disk device path like /dev/sda).

       For complete information, consult the section "Support for TCG Opal 2-compliant Self-Encrypting Disks" in
       the Relax-and-Recover user guide.

CONFIGURATION

To configure Relax-and-Recover you have to edit the configuration files in /etc/rear/. All *.conf files
there are part of the configuration, but only site.conf and local.conf are intended for the user
configuration. All other configuration files hold defaults for various distributions and should not be
changed.

In /etc/rear/templates/ there are also some template files which are used by Relax-and-Recover to create
configuration files (mostly for the boot environment). Modify the templates to adjust the information
contained in the emails produced by Relax-and-Recover. You can use these templates to prepend your own
configurations to the configuration files created by Relax-and-Recover, for example you can edit
PXE_pxelinux.cfg to add some general pxelinux configuration you use.

In almost all circumstances you have to configure two main settings and their parameters: The backup
method and the output method.

The backup method defines, how your data is to be saved and whether Relax-and-Recover should backup your
data as part of the mkrescue process or whether you use an external application, e.g. backup software to
archive your data.

The output method defines how the rescue system is written to disk and how you plan to boot the failed
computer from the rescue system.

See the default configuration file /usr/share/rear/conf/default.conf for an overview of the possible
methods and their options.

An example to use TSM for backup and ISO for output would be to add these lines to /etc/rear/local.conf
(no need to define a BACKUP_URL when using an external backup solution):

BACKUP=TSM
OUTPUT=ISO

And if all your systems use NTP for time synchronisation, you can also add these lines to
/etc/rear/site.conf

TIMESYNC=NTP

Do not forget to distribute the site.conf to all your systems.

The resulting ISO image will be created in /var/lib/rear/output/. You can now modify the behaviour by
copying the appropriate configuration variables from default.conf to local.conf and changing them to suit
your environment.

EXIT STATUS

       0
           Successful program execution.

       >0
           Usage, syntax or execution errors. Check the log file in /var/log/rear/ for more information.

EXAMPLES

       To print out the current settings for BACKUP and OUTPUT methods and some system information. This command
       can be used to see the supported features for the given release and platform.

           # rear dump

       To create a new rescue environment. Do not forget to copy the resulting rescue system away so that you
       can use it in the case of a system failure.

           # rear -v mkrescue

       To create a new rescue image together with a complete archive of your local system run the command:

           # rear -v mkbackup

FILES

       /usr/sbin/rear
           The program itself.

       /etc/rear/local.conf
           System specific configuration can be set here.

       /etc/rear/site.conf
           Site specific configuration can be set here (not created by default).

       /var/log/rear/
           Directory holding the log files.

       /tmp/rear.####
           Relax-and-Recover working directory. If Relax-and-Recover exits with an error, you must remove this
           directory manually.

       /usr/share/rear
           Relax-and-Recover script components.

       /usr/share/rear/conf/default.conf
           Relax-and-Recover default values. Contains a complete set of parameters and its explanation. Do not
           edit or modify things therein but use local.conf or site.conf for specific settings.

BUGS

       Feedback is welcome, please report issues or improvements to our issue-tracker at:
       http://github.com/rear/issues/

       Furthermore, we welcome pull requests via GitHub.

AUTHORS

       The ReaR project was initiated in 2006 by Schlomo Schapiro (https://github.com/schlomo) and Gratien
       D’haese (https://github.com/gdha) and has since then seen a lot of contributions by many authors. As ReaR
       deals with bare metal disaster recovery, there is a large amount of code that was contributed by owners
       and users of specialized hardware and software. Without their combined efforts and contributions ReaR
       would not be the universal Linux bare metal disaster recovery solution that it is today.

       As time passed the project was lucky to get the support of additional developers to also help as
       maintainers: Dag Wieers (https://github.com/dagwieers), Jeroen Hoekx (https://github.com/jhoekx),
       Johannes Meixner (https://github.com/jsmeix), Vladimir Gozora (https://github.com/gozora), Sebastien
       Chabrolles (https://github.com/schabrolles), Renaud Metrich (https://github.com/rmetrich) and Pavel
       Cahyna (https://github.com/pcahyna). We hope that ReaR continues to prove useful and to attract more
       developers who agree to be maintainers. Refer to the MAINTAINERS
       (https://github.com/rear/rear/blob/master/MAINTAINERS) file for the list of active and past maintainers.

       To see the full list of authors and their contributions look at the git history
       (https://github.com/rear/rear/graphs/contributors). We are very thankful to all authors and encourage
       anybody interested to take a look at our source code and to contribute what you find important.

       Relax-and-Recover is a collaborative process using Github at http://github.com/rear/

       The Relax-and-Recover website is located at: http://relax-and-recover.org/

COPYRIGHT

       (c) 2006-2022

       The copyright is held by the original authors of the respective code pieces as can be seen in the git
       history at https://github.com/rear/rear/graphs/contributors

       Relax-and-Recover comes with ABSOLUTELY NO WARRANTY; for details see the GNU General Public License at
       http://www.gnu.org/licenses/gpl.html

                                                   2023-12-03                                            REAR(8)