Error detection/correction and fault detection/recovery – Data processing system error or fault handling – Reliability and availability
Reexamination Certificate
2000-03-22
2003-07-01
Iqbal, Nadeem (Department: 2184)
Error detection/correction and fault detection/recovery
Data processing system error or fault handling
Reliability and availability
C714S022000
Reexamination Certificate
active
06587970
ABSTRACT:
FIELD OF THE INVENTION
The present invention is directed to information storage systems, and more particularly, to an information storage system that is capable of detecting a change in the operational status of a first host computer and changing the operation of a second host computer in response to the detected change.
DESCRIPTION OF THE RELATED ART
Providing replacement computer resources for a failed computer resource is termed site failover. Site failover is but one conventional example of a renewable host resource. Site failover from one computer system to another has historically been an expensive and labor intensive procedure. For example, to provide site failover for a first or primary computer system, a complete secondary or failover computer system was traditionally required. In the event of a failure of the primary computer system, the failover computer system would be brought up for use as a temporary replacement of the primary computer system, while the primary computer system was repaired.
To ensure that the failover computer system was a viable replacement for the primary computer system, data on the primary computer system would be periodically copied or backed up to the failover computer system for use in the event of failure of the primary computer system. Typically this back up would be performed manually over a network, or by tape, CD, or diskette. To facilitate site failover, the primary and failover computer systems were typically required to be identical, in terms of both hardware and software. In addition, to ensure that the failover computer system would be ready when needed, the failover computer system was typically maintained in an off state, until needed for replacing the primary computer system upon the failure of the primary computer system.
Years ago, site failures were typically due to a failure of the storage system to which a host computer was attached, rather than a failure of the host computer itself. This is because the storage system was frequently one of the least reliable components of the computer system. With the advent or more reliable storage systems featuring more reliable disk drives and other storage devices, data mirroring, data striping, etc., site failures are now more frequently caused by a failure in the host computer, rather than the storage system to which it is attached.
The use of more reliable storage systems has reduced some of the labor associated with site failover. Even so, some amount of manual intervention is still required. For example, when a failure occurs in a primary host computer, a new failover host computer still needs to be manually brought up in its stead. This typically requires powering down the primary host computer and the storage system, re-configuring cables that were previously connected between the primary host computer and the storage system to re-connect them between the failover host computer and the storage system, powering on the failover host computer system and the storage system, and then bringing the failover host computer up on-line as a replacement for the primary host computer.
Although the use of more reliable storage systems can dispense with the need for a complete failover computer system (i.e., failover host computer and failover storage system), conventional methods of site failover are expensive. For example, because some amount of manual intervention is still involved, conventional methods of site failover require skilled personnel to be on hand while the primary host computer is operational to effect site failover, when necessary. In addition, most conventional methods of site failover still require that the primary host computer and the failover host computer be identically configured in terms of both hardware and software to facilitate site failover. This duplication of resources is expensive, both initially and in terms of upgrades. For example, when advances in computer technology render a primary host computer obsolete, the identically configured failover host computer is also rendered obsolete. Furthermore, because the failover host computer is typically maintained in a powered-off state until needed, a great deal of computing resources are wasted.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, a method and apparatus for automatically configuring additional resources for a host computer is described. In one embodiment, a method is provided that includes acts of detecting a change in operation of a first host computer, and automatically configuring a second host computer to provide additional computational resources for the first host computer in response to the act of detecting.
According to another embodiment of the present invention, a computer system is provided. The computer system includes a first host computer, a second host computer, and a controller that is operatively coupled to the first host computer and the second host computer. The controller automatically configures the second host computer to provide additional computational resources for the first host computer in response to a change in operation of the first host computer.
According to another embodiment of the present invention, a computer system is provided that includes a first host computer, a second host computer, and configuration means, coupled to the first host computer and the second host computer, for automatically configuring the second host computer to provide additional computational resources for the first host computer in response to a change in operation of the first host computer.
According to another embodiment of the present invention, a storage system for use with a first host computer and a second host computer is provided. The storage system includes a first storage device to store data of the first host computer, and a controller that is coupled to the first storage device. The controller, when operatively coupled to the first host computer and the second host computer, automatically configures the second host computer to use the data of the first host computer and provide additional computational resources for the first host computer in response to a change in operation of the first host computer.
According to another aspect of the present invention, a method and apparatus for performing load balancing is described. In one embodiment, a method is provided that includes acts of detecting a decrease in performance of a first host computer, and automatically configuring a second host computer to provide additional computational resources for the first host computer in response to the act of detecting.
According to another embodiment of the present invention, a computer system is provided. The computer system includes a first host computer, a second host computer, and a controller that is operatively coupled to the first host computer and the second host computer. The controller automatically configures the second host computer to provide additional computational resources for the first host computer in response to a decrease in performance of the first host computer.
According to another embodiment of the present invention, a computer system is provided that includes a first host computer, a second host computer, and configuration means, coupled to the first host computer and the second host computer, for automatically configuring the second host computer to provide additional computational resources for the first host computer in response to a decrease in performance of the first host computer.
According to another embodiment of the present invention, a storage system for use with a first host computer and a second host computer is provided. The storage system includes a first storage device to store data of the first host computer, and a controller that is coupled to the first storage device. The controller, when operatively coupled to the first host computer and the second host computer, automatically configures the second host computer to use the data of the first host computer and provide additional computational resources for the first host compu
Chehadeh Mohamed
Vu Quang
Wang Yao
Bonura Tim M.
EMC Corporation
Iqbal Nadeem
Wolf Greenfield & Sacks P.C.
LandOfFree
Method and apparatus for performing site failover does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for performing site failover, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for performing site failover will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3110583