Description of the Acronis Universal Restore for Linux add-on
This article applies to:
- Acronis Backup & Recovery 11 Server for Linux
- Acronis Backup & Recovery 11 Advanced Server
- Acronis Backup & Recovery 11 Virtual Edition
Purpose of Acronis Universal Restore for Linux:
- Recovery of system bootability on dissimilar hardware
- Hardware-independent cloning and deployment of operating systems
- Physical-to-physical, physical-to-virtual and virtual-to-physical machine migration
Basic scenarios of when to use:
- Make the restored operating system bootable using Acronis Bootable Media when Acronis Universal Restore is installed
- Make the operating system bootable after hardware changes without image restore
How it works:
- Boot loader configuration changes - Acronis Universal Restore can automatically modify the configuration of the GRUB boot loader. This may be required, for example, to ensure the system bootability when the new machine has a different volume layout than the original machine.
- Patching drivers - When Acronis Universal Restore is applied to a Linux operating system, it updates a temporary file system known as the initial RAM disk (initrd). This ensures that the operating system can boot on the new hardware. Acronis Universal Restore adds modules for the new hardware (including device drivers) to the initial RAM disk. As a rule, it finds the necessary modules in the in the /lib/modules directory of the operating system you are recovering. If Universal Restore cannot find a module it needs, it records the module’s file name into the log.
(!) Acronis Universal Restore never modifies the Linux kernel.
(!) Despite the fact that Acronis Backup & Recovery 11 for Linux can work with kernel 2.4.20 or later, Acronis Universal Restore can be applied to Linux operating systems only with a kernel version of 2.6.8 or later.
You can revert to the original initial RAM disk if necessary.
The initial RAM disk is stored on the machine in a file. Before updating the initial RAM disk for the first time, Acronis Universal Restore saves a copy of it to the same directory. The name of the copy is the name of the file, followed by the _acronis_backup.img suffix. This copy will not be overwritten if you run Acronis Universal Restore more than once (for example, after you have added missing drivers).
To revert to the original initial RAM disk, do any of the following:
- Rename the copy accordingly. For example, run a command similar to the following:
mv initrd-18.104.22.168-0.21-default_acronis_backup.img initrd-22.214.171.124-0.21-default
- Specify the copy in the initrd line of the GRUB boot loader configuration.