Relax-and-Recover
=================
Relax-and-Recover is the leading Open Source bare metal disaster recovery
and system migration 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) as well as a multitude of backup strategies
(incl. IBM TSM, HP DataProtector, Symantec NetBackup, Bacula, rsync).
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 excuse for not having a disaster recovery solution implemented.
Recovering from disaster is made very straightforward 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 and integrating Relax-and-Recover into complex environments is made
possible by its modular framework. Consistent logging and optionally extended
output help understand the concepts behind Relax-and-Recover, troubleshoot
during initial configuration and help debug during integration.
Professional services and support are available as well.
For more detailed information about Relax-and-Recover, please read the
Relax-and-Recover User Guide.
REQUIREMENTS
------------
Relax-and-Recover is written entirely in Bash and does not require any
external programs. However, the rescue system that is created by
Relax-and-Recover requires some programs that are needed to make our
rescue system work:
- mingetty
- sfdisk
All other required programs (like sort, dd, grep, etc.) are so common, that
we don't list them as requirements. In case your specific workflow requires
additional tools, Relax-and-Recover will tell you.
INSTALLATION
------------
On RPM based systems you should use the rear RPM package. Either obtain it
from the Relax-and-Recover homepage or build it yourself from the TAR archive
with:
rpmbuild -ta rear-<version>.tar.gz
This will create an RPM for your distribution. The RPM is not platform-
dependant and should work also on other RPM based distributions.
On DEB based systems you should be able to install the RPM with alien.
Otherwise use the manual installation (see below) or, even better, contribute
the DEB package to the project.
QUICK START GUIDE
-----------------
This quick start guide will show you how to run Relax-and-Recover from the git
checkout and create a bootable USB backup.
Start by cloning the Relax-and-Recover sources from Github:
git clone https://github.com/rear/rear.git
Move into the rear/ directory:
cd rear/
Prepare your USB media. Change /dev/sdb to the correct device in your situation.
Relax-and-Recover will 'own' the device in this example.
***This will destroy all data on that device.***
sudo usr/sbin/rear format /dev/sdb
Relax-and-recover asks you to confirm that you want to format the device:
Yes
The device has been labeled REAR-000 by the 'format' workflow.
Now edit the 'etc/rear/local.conf' configuration file:
----
cat > etc/rear/local.conf <<EOF
### write the rescue initramfs to USB and update the USB bootloader
OUTPUT=USB
### create a backup using the internal NETFS method, using 'tar'
BACKUP=NETFS
### write both rescue image and backup to the device labeled REAR-000
BACKUP_URL=usb:///dev/disk/by-label/REAR-000
EOF
----
Now you are ready to create a rescue image. We want verbose output.
sudo usr/sbin/rear -v mkrescue
The output I get is:
----
Relax-and-Recover 1.13.0 / $Date$
Using log file: /home/jeroen/tmp/quickstart/rear/var/log/rear/rear-fireflash.log
Creating disk layout
Creating root filesystem layout
TIP: To login as root via ssh you need to set up /root/.ssh/authorized_keys
Copying files and directories
Copying binaries and libraries
Copying kernel modules
Creating initramfs
Writing MBR to /dev/sdb
Copying resulting files to usb location
----
You might want to check the log file for possible errors or see what
Relax-and-Recover is doing.
Now reboot your system and try to boot from the USB device.
If that worked, you can dive into the advanced Relax-and-Recover options and
start creating full backups. If your USB device has enough space, initiate a
backup using:
sudo usr/sbin/rear -v mkbackup
That is it. You are now better prepared for failure !
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 use by
Relax-and-Recover to create configuration files (mostly for the boot
environment). 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
(I put there stuff to install Linux over the network).
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 was 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 '/usr/share/rear/conf/default.conf' for an overview of the possible methods
and their options. An example to use TSM for backup and PXE for output and
would be to add these lines to '/etc/rear/local.conf':
----
BACKUP=TSM
OUTPUT=PXE
----
And since all your computers use NTP for time synchronisation, you should also
add these lines to '/etc/rear/site.conf':
----
TIMESYNC=NTP
----
Don't forget to distribute the 'site.conf' to all your systems.
The resulting PXE files (kernel, initrd and pxelinux configuration) will be
written to files 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.
USAGE
-----
To use Relax-and-Recover you always call the main script '/usr/sbin/rear':
----
# rear help
Usage: rear [-d] [-D] [-r KERNEL] [-s] [-S] [-v] [-V] COMMAND [ARGS...]
Relax-and-Recover comes with ABSOLUTELY NO WARRANTY; for details see
the GNU General Public License at: http://www.gnu.org/licenses/gpl.html
Available options:
-d debug mode; log debug messages
-D debugscript mode; log every function call
-r KERNEL kernel version to use; current: '2.6.32-131.2.1.el6.x86_64'
-s simulation mode; show what scripts rear would include
-S step-by-step mode; acknowledge each script individually
-v verbose mode; show more output
-V version information
List of commands:
checklayout check if the disk layout has changed
dump dump configuration and system information
format format and label media for use with rear
mkbackup create rescue media and backup system
mkbackuponly backup system without creating rescue media
mkrescue create rescue media only
validate submit validation information
Use 'rear -v help' for more advanced commands.
----
To view/verify your configuration, run +rear dump+. It will print out the
current settings for +BACKUP+ and +OUTPUT+ methods and some system information.
To create a new rescue environment, simply call +rear mkrescue+. Do not forget
to copy the resulting rescue system away so that you can use it in the case of
a system failure. Use +rear mkbackup+ instead if you are using the builtin
backup functions (like +BACKUP=NETFS+)
To recover your system, start the computer from the rescue system and run
+rear recover+. Your system will be recovered and you can restart it and
continue to use it normally.