Abstract: Embodiments include a checkpointing fault tolerance network architecture enables a first computer system to be remotely located from a second computer system. An intermediary computer system is situated between the first computer system and the second computer system to manage the transmission of checkpoint information from the first computer system to the second computer system in an efficient manner. The intermediary computer system responds to requests from the second computer system for updated data corresponding to memory pages selected by the second computer system, or memory pages identified through application of policy information defined by the second computer system.

Abstract: A checkpointing fault tolerance network architecture enables a backup computer system to be remotely located from a primary computer system. An intermediary computer system is situated between the primary computer system and the backup computer system to manage the transmission of checkpoint information to the backup VM in an efficient manner. The intermediary computer system is networked to the primary VM through a first connection and is networked to the backup VM through a second connection. The intermediary computer system identifies updated data corresponding to memory pages that have been less frequently modified by the primary VM and transmits such updated data to the backup VM through the first connection. In such manner, the intermediary computer system holds back updated data corresponding to more frequently modified memory pages, since such memory pages may be more likely to be updated again in the future.

Abstract: A system and related method of operation for migrating the memory of a virtual machine from one NUMA node to another. Once the VM is migrated to a new node, migration of memory pages is performed while giving priority to the most utilized pages, so that access to these pages becomes local as soon as possible. Various heuristics are described to enable different implementations for different situations or scenarios.

Abstract: Replicated data storage units are autonomously identified and assembled into generationally related data storage volumes. A data storage manager, implementing a re-signaturing process executed at defined intervals or manually initiated on a server or client system connected to the storage area network, scans the collection of visible data storage units to identify those related as a data storage volume. Each replicated data storage unit includes metadata that embeds an identification of the replicated data storage unit and volume accessible to the data storage manager. To assemble a set of replicated data storage units into a generational volume, the data storage unit metadata is rewritten to establish a unique data storage volume identity including information to associate the data storage volume in a lineage with the source data storage volume.

Abstract: In order to synchronize copies of a virtual disk, a virtualization layer maintains a first record of file system blocks of a first copy of the virtual disk that are modified during an access session by a virtual machine using the first copy of the virtual disk. The file system blocks correspond to a file system of the virtual disk. During an attempt to synchronize the first copy with a second copy of the virtual disk, (i) a second record of file system blocks that are currently used by the file system is obtained from the guest operating system, and (ii) file system blocks in the first copy of the virtual disk that are present in both the first record and the second record are copied into the second copy of the virtual disk.

Abstract: A virtualized computer system employs a virtual disk with a space efficient (SE) format to store data for virtual machines running therein. Data within a virtual disk with a SE format is stored in a grain, where multiple grains are included in a storage block. Writes to a grain within shared storage block in a virtual disk with an SE format are serviced by allocating a new grain and storing the write data to the new grain. Metadata associated with the client that transmitted the write request to the virtual disk is then updated to point to the new grain instead of the grain within the shared storage block.

Abstract: In a virtualized system running one or more virtual machines on a first hypervisor, a second hypervisor is installed and control of the hardware resources of the physical computer supporting the virtualized system is migrated from the first hypervisor to the second hypervisor without interrupting the operation of the first hypervisor and the virtual machines. Initially a minimal set of hardware resources is hot-removed from control by the first hypervisor, and the second hypervisor is launched on the minimal set of hardware resources. Both the remaining hardware resources and the virtual machines are then migrated from the first hypervisor to the second hypervisor until all the virtual machines have been migrated over to the second hypervisor, while the virtual machines and the first hypervisor continue running largely unaffected by the migration process.

Abstract: A method for detecting malicious code within a first virtual machine comprising creating a snapshot of the first virtual machine and transferring the snapshot to a second machine. A scan operation is run on the snapshot using resources of the second machine. In response to detecting malicious code during the scan operation, action is taken at the first virtual machine to address the detection of the malicious code. Thus, the action in response to detecting the malicious code may include placing the first virtual machine in quarantine.

Abstract: A method for replacing a current desktop image having a current operating system on storage media for a computing device is described. In the method, an agent process is executed on the computing device for downloading from a server to a staging area on local storage media a replacement desktop disk image having a replacement operating system. The replacement desktop image includes a prefetch set of files and metadata for additional files, the prefetch set of files including a minimal set of files necessary to boot the replacement operating system, the replacement desktop image not including contents of the additional files. The computing device is rebooted to replace the current desktop image with the replacement desktop image. The computing device is then rebooted again to load the replacement operating system using the prefetch set of files.