Section 12.4. System Cloning

12.4. System Cloning

In cloning, the system recovery archive is extracted onto a different physical computer from the computer that was used to generate the archive. This is the norm in many recovery scenarios. Cloning is also becoming popular with system administrators who seek shortcuts to managing systems with similar configurations.

When an archive is created from one system, many aspects of that system's configuration may be similar to those of other systems. For example, the systems may be on the same subnet with the same route tables. Or they may have the same network, SCSI, or Fibre Channel adaptor cards. Perhaps they even have the same model of disk arrays or tape librariesall running the same versions of various firmware. Yet there is still the potential for incompatibilities when using recovery archives to clone systems. The recovery process may fail if the system configuration stored in the archive is too dissimilar from the new target system.

When you attempt to restore an archive onto a system with different hardware, the system recovery tool should detect dissimilar hardware. This detection can normally be noticed at the system console during recovery. If the cloning process completes, it may become necessary to change system settings such as IP addresses or hostnames. This can be done post deployment, but these particular parameters can be modified prior to archive extraction using the Ignite-UX itool interface on the client console.

Consider an example in which a system targeted for archive recovery has a root volume group with different sized disks/LUNs or different numbers of disks, from those that were on the system that created the archive. Ignite-UX detects that the client system has a different hardware configuration and brings up the itool user interface on the client, from where the system administrator may reconfigure the related installation parameters concerning disks, volumes, and filesystems. If the system administrator does not manually reconfigure them, Ignite-UX attempts to modify logical volume and filesystem sizes during installation to ensure that there is, by default, 10 percent free space. If there is insufficient disk space for Ignite-UX to work with, it generates an error.