In some embodiments, a method receives a share of a signature of a decision block from at least a portion of the plurality of replicas. The share of the signature being generated when a respective replica signs the decision block and the decision block includes a set of requests from a client for a service. A combined signature is created based on the share of the signature block from at least the portion of the plurality of replicas. The method broadcasts a message that includes the combined signature to the plurality of replicas. The plurality of replicas use the combined signature to determine whether to process the decision block for the service.

A computer-implemented method at a data management system comprises: receiving, at a storage appliance from a server hosting a virtual machine, a write made to the virtual machine; computing, at the storage appliance, a fingerprint of the transmitted write; comparing, at the storage appliance, the computed fingerprint to malware fingerprints in a malware catalog; repeating the computing and comparing; and disabling the virtual machine if a number of matches from the comparing breaches a predetermined threshold over a predetermined amount of time.

A system of communicating data over a high availability industrial control system is disclosed. The industrial control system includes a first data producer, a second data producer in communicative connection with the first data producer, a first data consumer, and a second data consumer in communicative connection with the first data consumer. The system further includes the first producer communicating the data over multiple connection paths from the first producer to the first consumer and the second consumer through intermediate modules, and the second producer communicating the data over multiple connection paths from the second producer to the first consumer and the second consumer through intermediate modules. Also disclosed is a method of communicating data over the high availability industrial control system.

A maximum lag between data stores can be specified that corresponds to a recovery point objective defined in a service level agreement. Lag can be monitored during a data replication between a primary data store and a secondary data store located in geographically different regions. Activity on the primary data store including incoming data transactions can be throttled as a function of the lag and the maximum lag.

A method, system and computer program product for checkpointing virtual machines (VMs). The system includes a primary computer hosting a hypervisor and a primary VM. The hypervisor is configured instantiate the primary VM, divide the state of the primary VM into a plurality of memory blocks, and generate an error correction block based on the plurality of memory blocks. The system further includes a plurality of secondary computers. Each of the secondary computers stores a secondary VM and one of either the memory blocks or the error correction block.

Cloud computing is continuously growing as a business model for hosting information and communications technology applications. While the on-demand resource consumption and faster deployment time make this model appealing for the enterprise, other concerns arise regarding the quality of service offered by the cloud. Systems and methods are provided for enabling disaster recovery of applications hosted in the cloud and for monitoring data center sites for failure.

The disclosure describes a failure-free execution agreement that includes n=3F+1 parties acting as replicas, and a number of parties acting as clients. One replica is designated as a primary. At most F replicas are presumed Byzantine faulty. The basic agreement protocol proceeds in three rounds: (1) client sends a request to the primary, who sends to all replicas; (2) each replica sends a threshold-part signature on hash to a first collector; (3) the collector combines the threshold-parts into a single signature and sends to all 3F+1 replicas which then commit and send to a second collector. The client proceeds when a signed block of requests arrives from the second collector.

Apparatus adapted for exascale computers are disclosed. The apparatus includes, but is not limited to at least one of: a system, data processor chip (DPC), Landing module (LM), chips including LM, anticipator chips, simultaneous multi-processor (SMP) cores, SMP channel (SMPC) cores, channels, bundles of channels, printed circuit boards (PCB) including bundles, floating point adders, accumulation managers, QUAD Link Anticipating Memory (QUADLAM), communication networks extended by coupling links of QUADLAM, log2 calculators, exp2 calculators, logALU, Non-Linear Accelerator (NLA), and stairways. Methods of algorithm and program development, verification and debugging are also disclosed. Collectively, embodiments of these elements disclose a class of supercomputers that obsolete Amdahl's Law, providing cabinets of petaflop performance and systems that may meet or exceed an exaflop of performance for Block LU Decomposition (Linpack).

Systems and methods for facilitating test failover on a remote virtual machine without creating a full copy of the remote virtual machine. A snapshot is created of a remote virtual machine disk, the remote virtual machine disk protecting a source virtual machine disk. An instant, thin provisioned virtual machine is created from the snapshot, and the instant, thin provisioned virtual machine is powered on based on a received instruction to power on the instant, thin provisioned virtual machine thereby creating a running instance of a virtual machine, thereby facilitating test failover on the remote virtual machine without creating a full copy of the remote virtual machine.

A Management system 10 includes: resource pools 11.sub.1-11.sub.4 which act as the hardware components on which multiple virtual machines are running; an inter-connecting network 12 which connects various resource pools; and a HA manager 13 which snoops all traffic of the inter-connecting network 12 to detect failure of a target VM and triggers corresponded actions when failure is detected.