Pool of devices providing operating system redundancy

A method for providing operating system redundancy in a computing system including a host computing device coupled to a first logical unit device comprising a first physical memory disk and including a first operating system and to a second logical unit device comprising a second physical memory disk and including a second operating system via a sub-loader such that the host computing device sees the first and second logical unit devices and the sub-loader as a single memory device, the first operating system and the second operating system being clones of one another such that any modifications applied during operation of the first operating system are identically applied to the second operating system, the method comprising:

• designating, by the sub-loader, the first logical unit device as a primary logical unit device, the first logical unit device being a first type of memory device and having a first mirroring scheme;
• determining, by the sub-loader, that the first logical unit device is unresponsive pursuant to failing to receive a response to perform a functional request after a predetermined threshold of time;
• removing, by the sub-loader, the designation of primary logical unit device from the first logical unit device;
• designating, by the sub-loader, the second logical unit device as a new primary logical unit device after removal of the primary logical unit device designation from the first logical unit device, the second logical unit being a second type of memory device and selected to have a different mirroring scheme than the first mirroring scheme and to have a different redundant array of independent disks (RAID) configuration than the first logical unit device;
• maintaining by the sub-loader a first table for each of the first and second logical unit devices for tracking out-of-synch sectors on each respective logical unit device relative to sectors on the primary logical unit device, and maintaining a second table indicating which of the first and the second logical unit devices is the primary logical unit device;
• and
• after designating the second logical device as the new primary logical unit device, attempting to bring the first logical unit device back in synch with the new primary logical unit device so that the first logical unit device is available,
• wherein removing the primary logical unit device designation from the first logical unit device and designating the second logical unit device as the new primary logical unit device is transparent to the host computing device.

A computer program product for facilitating operating system redundancy, the computer program product comprising a non-transitory computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:

• a first executable portion for designating a first logical unit device as a primary logical unit device comprising a first physical memory disk and storing a first operating system, the first logical unit device being a first type of memory device;
• a second executable portion for determining that the first logical unit device is unresponsive pursuant to failing to receive a response to perform a functional request after a predetermined threshold of time;
• a third executable portion for removing the designation of primary logical unit device from the first logical unit device;
• a fourth executable portion for designating a second logical unit device as a new primary logical unit device after removal of the primary logical unit device designation from the first logical unit device, the second logical unit device comprising a second physical memory disk and including a second operating system, the second operating system being a clone of the first operating system such that any modifications applied during operation of the first operating system are identically applied to the second operating system, and the second logical unit device being a second type of memory device and selected to have a different mirroring scheme than the first mirroring scheme and to have a different redundant array of independent disks (RAID) configuration than the first logical unit;
• a fifth executable portion for maintaining a first table for each of the first and second logical unit devices for tracking out-of-synch sectors on each respective logical unit device relative to sectors on the primary logical unit device, and maintaining a second table indicating which of the first and the second logical unit devices is the primary logical unit device;
• and
• a sixth executable portion for, after designating the second logical device as the new primary logical unit device, attempting to bring the first logical unit device back in synch with the new primary logical unit device so that the first logical unit device is available,
• wherein removing the primary logical unit device designation from the first logical unit device and designating the second logical unit device as the new primary logical unit device is transparent to the host computing device.