Server failure is a major disaster in any organization. The magnitude of the failure can range from disk failure to critical system device failure. The former requires installation of new disks after which backups are restored. The latter may necessitate deployment of new hardware, whose configuration may be different to that which it is going to replace. Server restoration on a different hardware poses some problems.
To minimize downtime due to server failure in mission critical datacenters, implementation of failover/standby/backup server(s) is possible. This scenario provides quick restoration. One solution is to have two servers that are identical, both systems running together. Same hardware in both the main server and backup server is needed. Synchronization between the two servers must be done so as to restore any data changes on the main server to the backup server. Hardware synchronization is also necessary in the form of identical hardware updates. It is costly to maintain both servers from a maintenance and backup perspective. In situations where more than one mission critical server exists, the maintenance and backup costs become prohibitive. Added to the maintenance requirements of such server systems is the constraint to deploy hardware with identical configuration, which may not be easily available. Outsourcing the disaster recovery solution to a vendor that specializes in virtual machine technology overcomes this problem.
The virtual machine technology enables multiple operating systems to run concurrently on a single machine. Virtualization increases the efficiency and the effectiveness of the disaster recovery process and offers cost-savings opportunities. Virtualization is hardware-agnostic; systems can be restored without identical or near-identical hardware. This creates flexibility and expands options regarding the type of hardware one can recover to.
Disaster recovery can be implemented with hardware that need not be identical to the primary server. The standby server with server virtualization makes restoration of an entire server an easy process. With virtualization, restoring a server is as simple as retrieving a copy of the virtual machine’s image files and restoring them. This alone could reduce recovery time from hours or days to minutes.
The virtual server software hides the physical hardware from the virtual servers. The virtual server software creates a generic hardware platform that’s consistent, regardless of the physical hardware used to host the virtual servers. This simplifies the “bare metal” restore process, because it is possible to perform a bare metal install on dissimilar hardware
An organization with a number of servers must adopt a backup system, to ensure business continuity following a system crash, with the backup provider employing virtualization technologies.