Abstract: The “free world replication protocol” makes use of client computing resources, wherein the clients are not part of the replicated key-value store, but instead reside in the “free world” outside of the dedicated resources of the nodes of the replicated key-value store. In the free world replication protocol, only a single “write” client is authorized to modify the key-value store at any time but any number of clients may be authorized to read data from the key-value store. The write client sends its transactions to multiple nodes in the replicated key-value store. As a result, the latency between the transaction being sent from the client and the transaction being received by the multiple nodes is reduced. A consensus protocol, driven by a master node, is used to periodically ensure consistency, but the data transactions themselves do not make use of a master node.

Abstract: Uniformly-sampled, residue-generating analog-to-digital converters (ADCs), such as uniformly-sampled continuous-time pipelined ADCs, suffer from over-ranging of the residue signal, which can lead to severe signal distortion. Conventionally, power consuming techniques and oversampling are used to address the over-ranging problem. To reduce the range of the residue signal and reduce other impairments, an event-driven sub-quantizer (sub-ADC) and a sub-digital-to-analog converter (sub-DAC) can be implemented in at least one of the stages of the residue-generating ADC, to generate a continuous-time residue signal.

Abstract: Systems and methods which provide for managing multiple mirror resources in a storage distribution network are provided. In some embodiments, a system provides for both high availability and disaster recovery functionality at different mirroring locations. Other embodiments may provide for multiple high availability and/or multiple disaster recovery mirror resources. These mirror resources are operated in a heterogeneous manner in the sense that each have its own transport, protocol, and the like, but are configured function cooperatively or as a single mirror with respect to mirroring a primary node. Embodiments may provide for the mirroring and resynchronization of mirrored resources in the event of a communication loss with a particular resource without ceasing the mirroring operations to other resources.

Abstract: The “free world replication protocol” makes use of client computing resources, wherein the clients are not part of the replicated key-value store, but instead reside in the “free world” outside of the dedicated resources of the nodes of the replicated key-value store. In the free world replication protocol, only a single “write” client is authorized to modify the key-value store at any time but any number of clients may be authorized to read data from the key-value store. The write client sends its transactions to multiple nodes in the replicated key-value store. As a result, the latency between the transaction being sent from the client and the transaction being received by the multiple nodes is reduced by comparison to existing protocols in which each client sends transactions to a single node and that node forwards the transactions. A consensus protocol, driven by a master node, is used to periodically ensure consistency, but the data transactions themselves do not make use of a master node.

Abstract: The “free world replication protocol” makes use of client computing resources, wherein the clients are not part of the replicated key-value store, but instead reside in the “free world” outside of the dedicated resources of the nodes of the replicated key-value store. In the free world replication protocol, only a single “write” client is authorized to modify the key-value store at any time but any number of clients may be authorized to read data from the key-value store. The write client sends its transactions to multiple nodes in the replicated key-value store. As a result, the latency between the transaction being sent from the client and the transaction being received by the multiple nodes is reduced by comparison to existing protocols in which each client sends transactions to a single node and that node forwards the transactions. A consensus protocol, driven by a master node, is used to periodically ensure consistency, but the data transactions themselves do not make use of a master node.

Abstract: The “free world replication protocol” makes use of client computing resources, wherein the clients are not part of the replicated key-value store, but instead reside in the “free world” outside of the dedicated resources of the nodes of the replicated key-value store. In the free world replication protocol, only a single “write” client is authorized to modify the key-value store at any time but any number of clients may be authorized to read data from the key-value store. The write client sends its transactions to multiple nodes in the replicated key-value store. As a result, the latency between the transaction being sent from the client and the transaction being received by the multiple nodes is reduced by comparison to existing protocols in which each client sends transactions to a single node and that node forwards the transactions. A consensus protocol, driven by a master node, is used to periodically ensure consistency, but the data transactions themselves do not make use of a master node.

Abstract: A technique efficiently configures a peered cluster storage environment. The configuration technique illustratively includes three phases: a discovery phase, a node setup phase and a cluster setup phase. The discovery phase may be employed to initiate discovery of nodes of a disaster recovery (DR) group through transmission of multicast advertisement packets by the nodes over interconnects, including a Fiber Channel (FC) fabric, to each other node of the group. In the node setup phase, each node of a cluster assigns its relationships to the nodes discovered and present in the FC fabric; illustratively, the assigned relationships include high availability (HA) partner, DR primary partner and DR auxiliary partner. In the cluster setup phase, the discovered nodes of the FC fabric are organized as the peered cluster storage environment (DR group) configured to service data in a highly reliable and available manner.

Abstract: Systems and methods which provide for managing multiple mirror resources in a storage distribution network are provided. In some embodiments, a system provides for both high availability and disaster recovery functionality at different mirroring locations. Other embodiments may provide for multiple high availability and/or multiple disaster recovery mirror resources. These mirror resources are operated in a heterogeneous manner in the sense that each have its own transport, protocol, and the like, but are configured function cooperatively or as a single mirror with respect to mirroring a primary node. Embodiments may provide for the mirroring and resynchronization of mirrored resources in the event of a communication loss with a particular resource without ceasing the mirroring operations to other resources.

Abstract: Systems and methods which provide for managing multiple mirror resources in a storage distribution network are provided. In some embodiments, a system provides for both high availability and disaster recovery functionality at different mirroring locations. Other embodiments may provide for multiple high availability and/or multiple disaster recovery mirror resources. These mirror resources are operated in a heterogeneous manner in the sense that each have its own transport, protocol, and the like, but are configured function cooperatively or as a single mirror with respect to mirroring a primary node. Embodiments may provide for the mirroring and resynchronization of mirrored resources in the event of a communication loss with a particular resource without ceasing the mirroring operations to other resources.

Abstract: One or more techniques and/or systems are provided for interconnect failover between a primary storage controller and a secondary storage controller. The secondary storage controller may be configured as a backup or failover storage controller for the primary storage controller in the event the primary storage controller fails. Data and/or metadata describing the data (e.g., data and/or metadata stored within a write cache) may be mirrored from the primary storage controller to the secondary storage controller over one or more interconnect paths. Responsive to identifying a failover trigger for a failed interconnect path, the secondary storage controller is instructed to fence (e.g., block) I/O operations from the failed interconnect path. Streams of data and/or metadata that were affected by the failure may be instructed to transmit such data and/or metadata over one or more non-failed interconnect paths to the secondary storage controller during failover of the failed interconnect path.

Abstract: One or more techniques and/or systems are provided for interconnect failover between a primary storage controller and a secondary storage controller. The secondary storage controller may be configured as a backup or failover storage controller for the primary storage controller in the event the primary storage controller fails. Data and/or metadata describing the data (e.g., data and/or metadata stored within a write cache) may be mirrored from the primary storage controller to the secondary storage controller over one or more interconnect paths. Responsive to identifying a failover trigger for a failed interconnect path, the secondary storage controller is instructed to fence (e.g., block) I/O operations from the failed interconnect path. Streams of data and/or metadata that were affected by the failure may be instructed to transmit such data and/or metadata over one or more non-failed interconnect paths to the secondary storage controller during failover of the failed interconnect path.

Abstract: One or more techniques and/or systems are provided for interconnect failover between a primary storage controller and a secondary storage controller. The secondary storage controller may be configured as a backup or failover storage controller for the primary storage controller in the event the primary storage controller fails. Data and/or metadata describing the data (e.g., data and/or metadata stored within a write cache) may be mirrored from the primary storage controller to the secondary storage controller over one or more interconnect paths. Responsive to identifying a failover trigger for a failed interconnect path, the secondary storage controller is instructed to fence (e.g., block) I/O operations from the failed interconnect path. Streams of data and/or metadata that were affected by the failure may be instructed to transmit such data and/or metadata over one or more non-failed interconnect paths to the secondary storage controller during failover of the failed interconnect path.

Abstract: Systems and methods which provide for managing multiple minor resources in a storage distribution network are provided. In some embodiments, a system provides for both high availability and disaster recovery functionality at different mirroring locations. Other embodiments may provide for multiple high availability and/or multiple disaster recovery mirror resources. These mirror resources are operated in a heterogeneous manner in the sense that each have its own transport, protocol, and the like, but are configured function cooperatively or as a single minor with respect to minoring a primary node. Embodiments may provide for the minoring and resynchronization of mirrored resources in the event of a communication loss with a particular resource without ceasing the minoring operations to other resources.

Abstract: A technique efficiently configures a peered cluster storage environment. The configuration technique illustratively includes three phases: a discovery phase, a node setup phase and a cluster setup phase. The discovery phase may be employed to initiate discovery of nodes of a disaster recovery (DR) group through transmission of multicast advertisement packets by the nodes over interconnects, including a Fibre Channel (FC) fabric, to each other node of the group. In the node setup phase, each node of a cluster assigns its relationships to the nodes discovered and present in the FC fabric; illustratively, the assigned relationships include high availability (HA) partner, DR primary partner and DR auxiliary partner. In the cluster setup phase, the discovered nodes of the FC fabric are organized as the peered cluster storage environment (DR group) configured to service data in a highly reliable and available manner.

Abstract: One or more techniques and/or systems are provided for mirroring a caching log data structure from a primary storage controller to a secondary storage controller over multiple interconnect paths. The secondary storage controller may be configured as a backup or failover storage controller for the primary storage controller in the event the primary storage controller fails. Data and/or metadata describing the data may be mirrored from the primary storage controller to the secondary storage controller over one or more interconnect paths. The caching log data structure may be parsed into a plurality of streams. The streams may be assigned to interconnect paths between the primary storage controller and the secondary storage controller. A data ordering rule is enforced during mirroring of storage information of the streams across the interconnect paths (e.g., the secondary storage controller is to receive data in the order it was sent by respective streams).

Abstract: One or more techniques and/or systems are provided for interconnect failover between a primary storage controller and a secondary storage controller. The secondary storage controller may be configured as a backup or failover storage controller for the primary storage controller in the event the primary storage controller fails. Data and/or metadata describing the data (e.g., data and/or metadata stored within a write cache) may be mirrored from the primary storage controller to the secondary storage controller over one or more interconnect paths. Responsive to identifying a failover trigger for a failed interconnect path, the secondary storage controller is instructed to fence (e.g., block) I/O operations from the failed interconnect path. Streams of data and/or metadata that were affected by the failure may be instructed to transmit such data and/or metadata over one or more non-failed interconnect paths to the secondary storage controller during failover of the failed interconnect path.

Abstract: Systems and methods herein are operable to simultaneously mirror data to a plurality of mirror partner nodes. In embodiments, a mirror client may be unaware of the number of mirror partner nodes and/or the location of the plurality of mirror partner nodes, and issue a single mirror command requesting initiation of a mirror operation. An interconnect layer may receive the single mirror command and split the mirror command into a plurality of mirror instances, one for each mirror node partner, wherein the mirror instances may be simultaneously launched. After the plurality of mirror operations has begun, the interconnect layer may manage completion reports indicating the completion status of respective mirror operations, and send a single return to the mirror client indicating whether the mirror command succeeded.