Abstract: An information handling system includes a cloud device including an on-the-cloud analytics device, and a node device. The node device includes an on-the-box analytics device, a data collector device, a data management device, and a load mitigator device. The data collector device sources a plurality of data-producing agents within the information handling system. The data management device receives and manages data produced by the data collector. The load mitigator device receives the data from the data management device, and analyzes the data and additional system data. The additional system data is associated with the information handling system. The load mitigator device also determines whether to route analytics for the information handling system to the on-the box analytics device or to the on-the-cloud analytics. Based on the determination, the load mitigator device routes the analytics to either the on-the box analytics device or to the on-the-cloud analytics device.

Abstract: A method and system that migrates a subscriber session from a first authentication, authorization, and accounting (AAA) authentication server to a second AAA authentication server, where the first AAA authentication server is stateful. The method includes receiving an authenticate session request from a client application, sending (505) the authenticate session request to the first AAA authentication server, detecting (511) connectivity failure with the first AAA authentication server, and sending (513) a reauthentication required message to the client application.

Abstract: An apparatus comprises a processing device comprising a processor coupled to memory. The processing device is configured to obtain failover information corresponding to a first node of a plurality of nodes where each node is configured to communicate with a storage system over a plurality of paths. The failover information comprises a failover node selection order according to which other nodes of the plurality of nodes are configured for selection in response to the first node becoming unavailable. The processing device is configured to determine that health information corresponding to a given node indicates that the given node is exhibiting performance issues on at least one of the paths and to modify the failover node selection order based at least in part on the determination.

Abstract: A controller may identify a problematic path from several paths over which to route egress traffic from a site, may determine a threshold amount of traffic to shift from the problematic path, and may implement different potential traffic shifts for shifting similar amounts of traffic as the threshold amount. The controller may provide the labels or header values that different nodes in the site may place in the egress traffic in order to control which path is used to distributed that egress traffic. The controller may modify routing policies affecting different Autonomous System numbers, address prefixes, or other routing parameters to select and/or shift egress traffic, that is associated with those routing parameters and that is about equal to the threshold amount of traffic, from the problematic path to a different path.

Abstract: Techniques are described for using in-band communication channels to exchange state information between components of a distributed storage environment, including between client computing devices and storage servers hosting network-connected block storage volumes. The exchange of the state information can be used, for example, to inform client computing devices of relevant events involving one or more storage volumes attached to compute instances (for example, virtual machines (VMs)) running on the client computing devices, involving one or more failover servers storing backup copies of one or more storage volumes, or involving any other relevant system components.

Abstract: A data linkage system including a data collection system that collects data held by an information system and a data storage system that stores data held by a plurality of the information systems and collected by the data collection system includes a processing monitoring system that monitors processing at each stage on data in the data linkage system, and when processing which failed is detected, the processing monitoring system has this processing re-executed.

Abstract: In a data processing system having multiple production hosts, each with a backup agent, interfaced to a storage array and to a backup server, an array I/O priority engine on the storage array establishes and enforces I/O priorities for I/O backup and production communications with the array to ensure that backup does not consume a disproportionate CPU processing and array bandwidth load or disrupt more critical production processing.

Abstract: A method of storing and deleting data maintains a record of backups of the stored data, the record defining an entry for each backup comprising details of the data that has been backed up and the location of the data that has been backed up. The record of backups of the stored data is updated with a new entry every time at least part of the stored data is stored at a new location different from the first location. Once an instruction is received to delete the stored data, the maintained record of backups of the stored data is accessed, and an instruction is transmitted for each respective entry in the record of backups, the instruction comprising an instruction to delete the stored data at the respective location for the respective entry.

Abstract: Methods, apparatuses and systems for cloud-based disaster recovery are provided. The method, for example, includes configuring, at a cloud-based computing platform, a workload associated with a function-based service used by a client machine, the workload including generated steps listing servers associated with the function-based service and configured based on information provided by a user at the client machine; and restoring the servers for each of the generated steps of the workload including executing at least one of a pre-restore script, a post-restore script, or a manual input upon receiving, from the client machine, a failure indication associated with the servers.

Abstract: Techniques are described for handling stale variant cases that arise in adaptive streaming of content by media players. For example, embodiments include a delegate subsystem integrated with a media player client. The delegate subsystem can act as a proxy for requesting variant manifest update requests on behalf of the media player client and for receiving corresponding responses. The delegate subsystem can track the received update responses to determine whether the responses indicate a stale variant condition. If so, the delegate subsystem can issue a failover trigger to the media player client, such as by returning an error code, a variant gap tag, or the like. The failover trigger can cause the media player client 110 automatically to respond by executing a failover routine.

Abstract: Architectures and techniques are described that can enhance the functionality of a witness for an active-active storage array. In the event of a dual storage area network (SAN) failure, or another suitable event, host-array connectivity can take precedence for the witness in determining a winner or loser. Techniques are presented to identify connectivity issues and to utilize connectivity data in connection with determining a winner or a loser.

Abstract: Disclosed is a method of data concurrent recovery for a distributed storage system, that is, a method for synchronous repair of multiple failed nodes with a minimum recovery bandwidth when a node in a distributed storage system fails. First an assistant node is selected to get helper data sub-block, then the repair matrix related to the data block stored in the node to be repaired is constructed, and finally the lost data block is reconstructed by multiplying the repair matrix and the helper data helper data sub-block; the missing data block is reconstructed by decoding, wherein the node to be recovered includes all failed systematical nodes, or all or partly failed parity nodes. The method is applicable to concurrently recover multiple failed nodes at minimal recovery bandwidth, and the nodes to be recovered are selected according to the demand to reduce the recovery bandwidth as much as possible.

Abstract: Methods and apparatus to orchestrate infrastructure installation of a hybrid system are disclosed. An example apparatus includes a first virtual appliance including a management endpoint. The first virtual appliance is to organize tasks to be executed to install a computing infrastructure. The example apparatus includes a first component server to execute tasks. The component server includes a management agent to communicate with the management endpoint to receive a task to be executed to install the computing infrastructure. The first virtual appliance is to associate a role with the first component server and to determine whether the first component server satisfies a prerequisite associated with the role. The first virtual appliance is to facilitate addressing an error when the first component server is determined not to satisfy the prerequisite.

Abstract: A self-healing system configured to automatically restore non-responsive or failed applications to a normal operating state. A self-healing system may restart an application after confirming that the application itself has failed—and not an underlying dependency failure. The self-healing system may also evaluate a server hosting an application reported as being non-responsive to determine whether that server has itself failed. If an application is non-responsive or has failed on an otherwise healthy host, and the dependent service use by the application are available, the self-healing system automatically restores the application to a responsive state. To do so, the self-healing system may generate a run list specifying a sequence of scripts invoked to restore the application to the responsive state.

Abstract: A method, a system, and a computer program product for analysis of query filtering mechanisms for table fragments. A query plan for execution of a query is generated. The query requires access to at least one table stored in a database system. The query includes one or more filter predicates. The table is partitioned into a plurality of fragments. A determination whether a fragment in the table is compressed and whether the fragment is associated with an index is made. A filter predicate is selected for processing the fragment. For the selected filter predicate, a filter evaluation of the selected filter predicate for the fragment is determined. The filter evaluation of the selected predicate is executed for the fragment.

Abstract: Systems, methods, and computer program products are described herein for graphical user interface command patterns. A change request to a graphical user interface is received. A discrete command is generated based on the change request. The change request is temporarily rendered on the graphical user interface using the discrete command to retrieve local data. In parallel with the temporary rendering, backend data is retrieved in response to the discrete command. An update to the graphical user interface is rendered based on an existence of a delta between the local data and the backend data.

Abstract: A method, a system, and a computer program product for executing a query. The query requiring access to one or more tables stored in a database system is executed. The query includes one or more filter predicates. Using a unique key value corresponding to a first predicate, at most one row in the tables including a portion of data matching the unique key value is identified. Using filter values corresponding to the filter predicates, another portion of data in the identified row is compared to the filter values to determine whether that portion of data matches the filter values. Based on the comparison, a result of the execution of the query is outputted. The result includes data stored in the identified row upon determination that the data matches the unique key value corresponding to the first filter predicate and the filter values corresponding to remaining filter predicates. Otherwise, the result is empty.

Abstract: Embodiments of the present disclosure relate to a method, device, and computer program product for scheduling backup jobs. There is provided a method of scheduling backup jobs, comprising: in response to detecting that a target backup job is generated, obtaining predetermined execution information of the target backup job; determining an execution priority of the target backup job based on the predetermined execution information of the target backup job; determining an execution priority of an existing backup job in a waiting queue; and adding the target backup job to the waiting queue based on the execution priority of the existing backup job and the execution priority of the target backup job. Through embodiments of the present disclosure, it enables better utilization of system resources to achieve the Recover Point Objective for important data, ensuring a Service Level Agreement.

Abstract: A method for enabling (virtualized) application functions ((V)AFs) to associate to underlying (virtualized) network functions ((V)NFs) is provided in a Network Function Virtualization (NFV) environment in which a lifecycle management (LCM) of the (V)AFs and its associations with the underlying (V)NFs and resources are managed by the NFV Management and Orchestration (MANO) system. A service request is validated by an NFV Orchestrator (NFVO) parsing an (V)AF Descriptor ((V)AFD) file within an (V)AF catalogue. An (V)AF Record ((V)AFR) instance is created having information useable to maintain a state and one or more associations of the respective (V)AF. The NFVO, in cooperation with a Virtualized Network Function Manager (VNFM), Virtualized Infrastructure Manager (VIM) and an underlying network controller of the NFV MANO system, establishes the association between the respective (V)AF and the respective underlying (V)NF(s) using the (V)AFD.

Abstract: Aspects of the present disclosure involve systems, methods, computer program products, and the like, for providing a failover system and method for one or more collaboration conference web adapters. In general, the system and method allow for the movement of traffic or other communication packets associated with a collaboration conference from one adapter located in a first data center to another adapter located in a second data center. In one embodiment, the failover may occur in response to the detection or determination of a failure or loss of an operational state at an adapter of the system. In another embodiment, the failover may occur in response to a selection from an operations center to move the traffic to the selected adapter or second data center.

Abstract: Implementations of this specification provide a method and an apparatus for changing a master node in a blockchain system. An example method performed by a backup node in the blockchain system includes determining that an epoch change is to occur in a blockchain system, generating a random number, and in response to determining that the random number satisfies an epoch change trigger condition, sending an epoch change request message to multiple network nodes other than the backup node in the blockchain system. The backup node receives a request acknowledgement message from at least one of the multiple network nodes, the request acknowledgement message indicating that the backup node is to serve as the new master node, and in response to receiving a number of request acknowledgement messages that is greater than a predetermined number of messages, the backup node sends an epoch change acknowledgement message to the multiple network nodes.

Abstract: Embodiments of this application relate to an intra-cluster node troubleshooting method and device. The method includes: obtaining fault detection topology information of a cluster, where the fault detection topology information includes a fault detection relationship between all nodes in the cluster; obtaining a fault indication message, where the fault indication message is used to indicate unreachability from a detection node to a detected node; determining a sub-cluster of the cluster based on the fault detection topology information and the fault indication message, where nodes that belong to different sub-clusters are unreachable to each other; and determining a working cluster based on the sub-cluster of the cluster. According to the embodiments of this application, available nodes in the cluster can be retained to a maximum extent at relatively low costs. In this way, a quantity of available nodes in the cluster is increased, high availability is ensured.

Abstract: Described herein is a system that provides data service failover in shared storage clusters. An example shared storage cluster can include multiple data node devices equipped to access to a shared storage location. Each of the data node devices can host multiple network attached storage (NAS) servers. For each NAS server at a data node device, a different data node device in the shared storage cluster can be designated as a backup node. The designated backup nodes for NAS servers at any one data node device in the shared storage cluster can be distributed across multiple other data node devices in the shared storage cluster, thereby sharing the burden of data node device failure across multiple other data node devices.

Abstract: Systems and methods for providing data storage operations, such as archiving and/or backing up of data, for mail servers, such as Exchange servers, via a Simple Mail Transfer Protocol (SMTP) interface are described. For example, the systems and methods may provide an SMTP server between one or more Exchange servers and a media agent, which is configured to performing secondary copy operations, in order to quickly and/or efficiently generate archive or other secondary copies of various mailboxes within the mail server before or during the transfer of mail data to the media agent for data storage operations.

Abstract: Techniques for providing a backup network path using a standby wide area network (WAN) link with reducing monitoring. Packet loss and latency metrics are monitored for network paths in an adaptive private network (APN) connecting a first user and a second user according to control traffic operating at a first control bandwidth for each network path. A determination is made that a first network path uses a standby WAN link, has packet loss and latency metrics indicative of a good quality state, and has at least one characteristic that identifies the first network path as a backup network path. The control traffic is then reduced for the backup network path to a second control bandwidth substantially less than the first control bandwidth. The backup network path is made active when the number of active network paths is less than or equal to a minimum number.

Abstract: A method for performing security failover in an industrial production environment includes a programmable logic controller (PLC) receiving notification that a function block (FB) or a function (FC) on the programmable logic controller has been maliciously revised. The PLC next determines whether the function block or the function is also maliciously revised on a failover computing device. If the failover computing device is not maliciously revised, a failover operation is performed by the PLC. This operation includes sending a data block comprising one or more input parameters to the function block or the function and receiving an output data resulting from executing the function block or the function with the data block on the failover computing device.

Abstract: Examples herein relate to identifying a soft failure at member within a cluster dedicated to a microservice. Examples disclose identifying a statistical evaluation for each member within the cluster. Based on the statistical evaluation, identifying a soft failure among one of multiple members within the cluster. In response to the identification of the soft failure at one of the members within the cluster, performing an action.

Abstract: Systems and methods described herein include receiving, from a first network function, a request to receive a notification when a second network function becomes available after a failure. A status update may be received from the second network function indicating that the second network function is available. It may be determined that the second network function is in a stable state. A notification may be sent, to the first network function, that the second network function is available along with an indication of a time period in which to switch from accessing a third network function to accessing the second network function.

Abstract: A system and method for addressing failures in electronic display assemblies is provided. Each of a plurality of electronic display assembles include an electronic display, one or more components for operating the electronic display assembly, and a control device. A network operations center is located remote from, but in electronic communication with, each of the electronic display assembles. If the control devices determine that any of the components are not operating properly, the control device is configured to remove the power supplied to the components, wait a predetermined amount of time, and resume applying power.

Abstract: A system and method for triggering a recovery action during a component disruption in a production environment includes receiving data inputs from a plurality of components comprising the production environment, detecting an abnormality associated with a component of the plurality of components by analyzing the data inputs, and in response to the detecting the abnormality, triggering an analysis of the abnormality, analyzing the abnormality using a plurality of artificial intelligence engines to determine a plurality of outcomes from each artificial engine, consolidating the plurality of outcomes into a single outcome, the single outcome being input into an annotator engine to determine the recovery action to take during the component disruption in the production environment, and implementing the recovery action specific to the component with the detected abnormality.

Abstract: Techniques for load balancing and fault tolerant service are described. An apparatus may comprise load balancing and fault tolerant component operative to execute a load balancing and fault tolerant service in a distributed data system. The load balancing and fault tolerant service distributes a load of a task to a first node in a cluster of nodes using a routing table. The load balancing and fault tolerant service stores information to indicate the first node from the cluster of nodes is assigned to perform the task. The load balancing and fault tolerant service detects a failure condition for the first node. The load balancing and fault tolerant service moves the task to a second node from the cluster of nodes to perform the task for the first node upon occurrence of the failure condition.

Abstract: An automatic failure recovery system that, using machine learning, creates an operation procedure for recovering from a network failure or corrects the created operation procedure has a plurality of recovery tasks for recovering from the network failure; outputs failure data indicating network configuration information and failure information acquired upon occurrence of the network failure; selects an execution procedure of the recovery tasks, based on the failure data and a recovery model acquired in advance; executes the selected execution procedure when the network failure occurs; determines whether or not recovery from the network failure was achieved by the execution procedure; and notifies that the procedure is to be corrected, depending upon the result of the determination and a recovery level of the network failure.

Abstract: A method of operating a storage system is provided. The method includes detecting differing amounts of storage memory on two or more of a plurality of blades of the storage system and forming a plurality of resiliency groups of blades, based on the differing amounts of storage memory, each resiliency group comprising a subset of the plurality of blades of the storage system supporting data recovery in case of failure of two of the blades of the resiliency group.

Abstract: A printed circuit (PC) card apparatus can, in an absence of external power provided to a Peripheral Component Interconnect Express (PCIe) PC card, prevent and detect unauthorized access to secure data stored on a memory device mounted on the PCIe PC card. The PCIe card includes a primary battery to supply, when external power is disconnected from the PCIe card, power to an electronic security device mounted on the PCIe card. The PC card apparatus also includes a PCIe edge connector protector enclosing electrically conductive fingers of a PCIe edge card connector. The PCIe edge connector protector includes a hidden supplemental charge storage device integrated into the PCIe edge connector protector. The PCIe edge connector protector also includes electrically conductive contacts to transfer supplemental power from the supplemental charge storage device to the electronic security device.

Abstract: In one embodiment, a device in a network predicts failure of a network element in the network using a machine learning-based failure prediction model. The device updates, based on the predicted failure of the network element, a topology of the network to remove the network element from the topology of the network. The device recomputes a reactive routing table of the device using the updated topology of the network. The device notifies one or more other devices of the network of the predicted failure using a reactive routing protocol message.

Abstract: This disclosure relates generally to storage device, and more particularly to method and system for dynamically allocating front end ports in a storage device. In one embodiment, the method may include determining a need for re-allocating a set of servers being served by a first set of front end ports from among a plurality of front end ports of the storage device, evaluating remaining ports of the plurality of front end ports to identify a second set of front end ports to serve the set of servers, dynamically updating a configuration of each of the plurality of front end ports by emulating virtual worldwide names (vWWNs) of the first set of front end ports onto the second set of front end ports, and serving the set of servers from the second set of front-end ports based on the updated configuration.

Abstract: Bus enumeration of a switch fabric bus may be performed without assigning bus numbers to unused switch ports and/or corresponding slots to which the unused switch ports are routed. Accordingly, switches coupled to a switch fabric bus in a chassis may link-train with corresponding slots in the chassis in an attempt to establish active connections with devices coupled to the slots. Unused switch fabric bus lanes running from the switches to unused slots may be identified, and the unused switch ports corresponding to the unused switch fabric bus lanes may be disabled. During a subsequent bus enumeration procedure for the switch fabric bus, bus numbers may be allocated to the identified used switch ports (or corresponding used slots) but not to the identified unused switch ports (or corresponding unused slots). The link training, used/unused switch port identification, and bus enumeration may all be performed each time the chassis is reset.

Abstract: Some embodiments provide a system and method associated with improving resilience for a non-high availability service provided by a multi-node cluster (e.g., a bosh-based database service). A processor of a node in the cluster may determine that a lifecycle event has occurred (e.g., an initial deployment, failover, or deployment update). Responsive to the lifecycle event, the processor may store information about a role of a master node and timestamp information (e.g., on persistent storage). The processor may subsequently determine that a cluster deployment crash has occurred for the service. Timestamp information associated with multiple nodes may then be compared to establish one of the nodes as the master node. For example, the most recent timestamp may be used to establish the master node.

Abstract: Provided are a computer program product, system, and method for generating a health condition message on a health condition detected at a first server to send to a host system accessing the first server. A determination is made of a health condition with respect to access to a first storage. A determination is made of an estimated Input/Output (I/O) delay to access the first storage resulting from the determined health condition. A health condition message is generated indicating the estimated I/O delay. The health condition message is transmitted to the host system, wherein the host system uses the estimated I/O delay to determine whether to perform a swap operation to redirect host I/O requests to data from the first server to a second server.

Abstract: A system and method for automatic and dynamic virtual machine (VM) group membership adjustment to identify and maintain VM groupings for maintaining a data consistency and availability at a computer recovery site in response to a disaster event. Based on a hybrid approach of network and storage analytics using cognitive methods, the system automatically groups the VMs based on patterns of data exchanged between the VMs. The system can store the patterns found during the analysis, find the critical elements in those patterns (like VMs playing the key role of DB server), match the patterns and use them in case a detected failure to make the system functional again at the recovery site. The system stores the communications traffic patterns learned during the network analysis and uses analytics to form or change the VM grouping, and can perform the pattern matching to quickly readjust the group.

Abstract: A system can include one or more content distribution sites to provide content to one or more content satellite offices for delivery toward a set of destination devices for display. A content distribution site, of the one or more content distribution sites, can include one or more streamer devices. The one or more streamer devices can be associated with a single spoofed Internet protocol (IP) address. The spoofed IP address can facilitate failover among the one or more streamer devices. The one or more streamer devices can be configured to provide the content toward the set of destination devices using multicast with forward error correction (FEC). A content satellite office, of the one or more content satellite offices, can be configured to subscribe to a multicast group associated with the one or more streamer devices. The multicast group can be associated with the spoofed IP address to facilitate the failover among the one or more streamer devices.

Abstract: A device determines traffic and costs associated with a network that includes network devices interconnected by links, and determines traffic assignments for the network based on the traffic and the costs associated with the network. The device determines tunnel use for the network based on the traffic assignments, and determines peer link use for the network based on the tunnel use. The device determines costs associated with the traffic assignments, the tunnel use, and the peer link use for the network, and generates traffic plans based on the traffic assignments, the tunnel use, the peer link use, and the costs associated with the traffic assignments, the tunnel use, and the peer link use. The device causes one of the traffic plans to be implemented in the network by the network devices and the links.

Abstract: A route selection method, a route selection system, a network acceleration node, and a network acceleration system are provided. The route selection method comprises detecting, by an ingress network acceleration node, a link delay from the ingress network acceleration node to each egress network acceleration node, and determining whether each egress network acceleration node is available; obtaining, by the ingress network acceleration node, from an available egress network acceleration node, a link delay from the available egress network acceleration node to a source site IP; and selecting a desired route from the ingress network acceleration node to the source site IP based on a link delay from the ingress network acceleration node to an available egress network acceleration node and a link delay from the available egress network acceleration node to the source site IP.

Abstract: Mitigating the effects of a real node failure in a mapped redundant array of independent nodes, e.g., mapped cluster is disclosed. In response to a change in an accessibility to data stored on a real storage device of a real node of a real cluster, wherein the real storage device corresponds to a mapped storage device of a mapped node of a mapped cluster, substituting a reserved real storage device for the real storage device. The substituting the reserved real storage device can correspond to a change in a topology of the mapped cluster, wherein the change in the topology comprises replacing the mapped storage device with a substitute mapped storage device that corresponds to the replacement real storage device. The changed topology can enable writing of data to the substitute mapped storage device that can cause writing of corresponding data to the reserved real storage device.

Abstract: Aspects of the present invention include a method, system and computer program product. The method includes a processor operating first and second physical channel identifier (PCHID) devices comprised of a plurality of functional logic components, wherein one or more of the functional logic components are specific to one or more of the first and second PCHIDs and wherein one or more of the functional logic components are in common and not specific to one or more of the first and second PCHIDs; determining that an error condition exists in the first PCHID or the second PCHID; and executing a recovery method to remove the error condition from the first PCHID or the second PCHID in which the error condition exists.

Abstract: The present invention relates to a data processing system for providing business continuity protection, comprising: a business center comprising a first data processing unit, a first pre-communication unit, and at least a first post-communication unit; a disaster recovery center comprising a second data processing unit, a second pre-communication unit, and at least a second post-communication unit; wherein the first pre-communication unit and the second pre-communication unit are communicatively coupled to the first post-communication unit respectively when the business center operates normally; the first pre-communication unit and the second pre-communication unit are communicatively coupled to the second post-communication unit respectively when the disaster recovery center operates in place of the business center. The data processing system can reliably switch between the business center and the disaster recovery center, thereby providing a complete protection for the business continuity.

Abstract: A distributed key-value storage system may include a master node. The key-value store may be distributed among first and second nodes. The master node may receive a publish request to publish one or more key-value pairs. Each key-value pair may be stored in a retransmit buffer and sent to all the first nodes using a communication protocol of a first kind that does not include a retransmit protocol mechanism. Some of the key-value pairs may be sent to one or more second node using a communication protocol of a second kind that includes a retransmit protocol mechanism.

Abstract: The present invention relates to communications methods and apparatus for detecting and/or mitigating split brain occurrences in high availability systems. A split brain condition being a condition wherein both a standby processing node and another processing node of a cluster of processing nodes included in a high availability system are both operating at the same time in an active mode of operation. An exemplary method embodiment of operating a high availability system including a plurality of processing nodes includes the steps of determining at a standby processing node that a failure condition exists, said standby processing node being one of the cluster of processing nodes; switching the standby processing node from a standby mode of operation to an active mode of operation in response to determining that a failure condition exists; and determining whether the high availability system is experiencing a split brain condition.

Abstract: A Distributed Availability Group (DAG) spans two AGs, each spanning one or more replica nodes and functioning as primary or secondary AG. A primary AG is replicated to the secondary AG synchronously or asynchronously. A failover in the DAG results in the AGs swapping their roles. Multiple DAGs can be linked together as a chain, which provides many useful features including disaster recovery across geographical regions, massive read scale (numerous readable secondary nodes), online migration of databases (across different operating systems and computing environments). The systems using DAGs can replicate databases across multiple independent high availability (HA) failover clusters using complex replication topologies and allow for manual failover and failback. The systems allow chaining of multiple AGs to provision a treelike structure of replicas and numerous secondary replicas without impacting performance.

Abstract: Methods and apparatus are described for stitching independently encoded content streams together such that they appear to be part of a single streaming session.