Abstract: Direct monitoring of a plurality of storage nodes in a primary cluster is performed based on connectivity with the storage nodes. Indirect monitoring of a first storage node is performed, in response to direct monitoring of the first storage node indicating failure of the connectivity with the first storage node, wherein a second storage node of the plurality of nodes is a backup node for the first storage node. The indirect monitor of the first storage node indicates failure of the first storage node in response to performance of storage access operations by the second storage node that were previously performed by the first storage node. A cluster-switch operation is initiated to switch to from the primary cluster to a backup cluster based on an occurrence of at least one cluster-failure condition that comprises the indirect monitor of the first storage node indicating failure of the first storage node.

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: Monitoring health of associated, but separated storage clusters can be done at both a node scope and a cluster scope. Monitoring the storage clusters at the cluster scope includes monitoring the network elements that support the storage clusters and connect the storage clusters. Initially, a fabric monitor in each cluster discovers cluster topology. This cluster topology is communicated and maintained throughout the managing storage elements of the storage clusters. After the storage cluster topologies have been discovered, the fabric monitors of each cluster can periodically determine status of network elements of the storage clusters. This allows the storage clusters to maintain awareness of interconnect status, and react to changes in status. In addition, each managing storage element monitors its own health. This information is aggregated to determine when to trigger corrective actions, alerts, and/or storage features in accordance with rules defined at the managing storage elements.

Abstract: A storage controller receives data from a host. The data is provided to a storage stack on the storage controller. The storage stack can perform deduplication, compression or file layout operations on the data, which is then written to a first storage unit coupled to a first port of the storage controller. The storage controller determines whether a second port of the first storage controller is configured as a remote port. In response to determining that the second port is configured as a remote port, the data is also provided to a pass-thru stack on the first storage controller. The pass-thru stack performs protocol conversion on the data and writes the data to the second port on the storage controller.

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: Direct monitoring of a plurality of storage nodes in a primary cluster is performed based on connectivity with the storage nodes. Indirect monitoring of a first storage node is performed, in response to direct monitoring of the first storage node indicating failure of the connectivity with the first storage node, wherein a second storage node of the plurality of nodes is a backup node for the first storage node. The indirect monitor of the first storage node indicates failure of the first storage node in response to performance of storage access operations by the second storage node that were previously performed by the first storage node. A cluster-switch operation is initiated to switch to from the primary cluster to a backup cluster based on an occurrence of at least one cluster-failure condition that comprises the indirect monitor of the first storage node indicating failure of the first storage node.

Abstract: A storage controller receives data from a host. The data is provided to a storage stack on the storage controller. The storage stack can perform deduplication, compression or file layout operations on the data, which is then written to a first storage unit coupled to a first port of the storage controller. The storage controller determines whether a second port of the first storage controller is configured as a remote port. In response to determining that the second port is configured as a remote port, the data is also provided to a pass-thru stack on the first storage controller. The pass-thru stack performs protocol conversion on the data and writes the data to the second port on the storage controller.

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.