Abstract: One or more techniques and/or systems are provided for storage device health status synchronization. For example, a first health status registry is maintained for a first storage controller at a first storage site. The first storage controller stores storage device health status information of storage devices currently owned by or assigned to the first storage controller within the first health status registry. A second health status registry is maintained for a second storage controller at a second storage site. The second storage controller stores storage device health status information of storage device currently owned by or assigned to the second storage controller within the second health status registry. The first health status registry and the second health status registry are synchronized during operation of the first storage site and the second storage site and/or are merged between the first storage site and the second storage site after disaster recovery.

Abstract: One or more techniques and/or systems are provided for storage device health status synchronization. For example, a first health status registry is maintained for a first storage controller at a first storage site. The first storage controller stores storage device health status information of storage devices currently owned by or assigned to the first storage controller within the first health status registry. A second health status registry is maintained for a second storage controller at a second storage site. The second storage controller stores storage device health status information of storage device currently owned by or assigned to the second storage controller within the second health status registry. The first health status registry and the second health status registry are synchronized during operation of the first storage site and the second storage site and/or are merged between the first storage site and the second storage site after disaster recovery.

Abstract: One or more techniques and/or systems are provided for storage device health status synchronization. For example, a first health status registry is maintained for a first storage controller at a first storage site. The first storage controller stores storage device health status information of storage devices currently owned by or assigned to the first storage controller within the first health status registry. A second health status registry is maintained for a second storage controller at a second storage site. The second storage controller stores storage device health status information of storage device currently owned by or assigned to the second storage controller within the second health status registry. The first health status registry and the second health status registry are synchronized during operation of the first storage site and the second storage site and/or are merged between the first storage site and the second storage site after disaster recovery.

Abstract: In one aspect of the disclosure, progress identifiers (e.g., a plurality of flags) and/or generation numbers are utilized to determine a “correct” non-volatile random access memory (NVRAM) replay source to use during a retried switchover or early switchback. Initially, a switchover sequence is initiated. The switchover sequence includes a replay of logged information to storage devices of an aggregate to ensure data consistency of the aggregate. Progress of the switchover sequence is tracked using the progress identifiers and/or generation numbers. After an interruption during the switchover sequence, switchover is retried or an early switchback is performed. The retried switchover or early switchback decides whether to replay logged information, and, if so, determines an NVRAM replay source to replay logged information from based on states of the progress identifiers and/or comparison of the generation numbers.

Abstract: One or more techniques and/or systems are provided for storage device health status synchronization. For example, a first health status registry is maintained for a first storage controller at a first storage site. The first storage controller stores storage device health status information of storage devices currently owned by or assigned to the first storage controller within the first health status registry. A second health status registry is maintained for a second storage controller at a second storage site. The second storage controller stores storage device health status information of storage device currently owned by or assigned to the second storage controller within the second health status registry. The first health status registry and the second health status registry are synchronized during operation of the first storage site and the second storage site and/or are merged between the first storage site and the second storage site after disaster recovery.

Abstract: In one aspect of the disclosure, progress identifiers (e.g., a plurality of flags) and/or generation numbers are utilized to determine a “correct” non-volatile random access memory (NVRAM) replay source to use during a retried switchover or early switchback. Initially, a switchover sequence is initiated. The switchover sequence includes a replay of logged information to storage devices of an aggregate to ensure data consistency of the aggregate. Progress of the switchover sequence is tracked using the progress identifiers and/or generation numbers. After an interruption during the switchover sequence, switchover is retried or an early switchback is performed. The retried switchover or early switchback decides whether to replay logged information, and, if so, determines an NVRAM replay source to replay logged information from based on states of the progress identifiers and/or comparison of the generation numbers.

Abstract: One or more techniques and/or systems are provided for storage device health status synchronization. For example, a first health status registry is maintained for a first storage controller at a first storage site. The first storage controller stores storage device health status information of storage devices currently owned by or assigned to the first storage controller within the first health status registry. A second health status registry is maintained for a second storage controller at a second storage site. The second storage controller stores storage device health status information of storage device currently owned by or assigned to the second storage controller within the second health status registry. The first health status registry and the second health status registry are synchronized during operation of the first storage site and the second storage site and/or are merged between the first storage site and the second storage site after disaster recovery.

Abstract: One or more techniques and/or systems are provided for load balancing between storage controllers. For example, a first storage controller and a second storage controller may be configured at a first storage site according to a high availability configuration, and may be configured as disaster recovery partners for a third storage controller and a fourth storage controller at a second storage site. If the first storage controller fails, the second storage controller provides failover operation for a first storage device. If a disaster occurs at the second storage site, the second storage controller provides switchover operation for a third storage device and a fourth storage device. Responsive to the first storage controller being restored, the third storage device may be reassigned from the second storage controller to the first storage controller for load balancing at the first storage site during disaster recovery of the second storage site.

Abstract: In one aspect of the disclosure, progress identifiers (e.g., a plurality of flags) and/or generation numbers are utilized to determine a “correct” non-volatile random access memory (NVRAM) replay source to use during a retried switchover or early switchback. Initially, a switchover sequence is initiated. The switchover sequence includes a replay of logged information to storage devices of an aggregate to ensure data consistency of the aggregate. Progress of the switchover sequence is tracked using the progress identifiers and/or generation numbers. After an interruption during the switchover sequence, switchover is retried or an early switchback is performed. The retried switchover or early switchback decides whether to replay logged information, and, if so, determines an NVRAM replay source to replay logged information from based on states of the progress identifiers and/or comparison of the generation numbers.

Abstract: One or more techniques and/or systems are provided for load balancing between storage controllers. For example, a first storage controller and a second storage controller may be configured at a first storage site according to a high availability configuration, and may be configured as disaster recovery partners for a third storage controller and a fourth storage controller at a second storage site. If the first storage controller fails, the second storage controller provides failover operation for a first storage device. If a disaster occurs at the second storage site, the second storage controller provides switchover operation for a third storage device and a fourth storage device. Responsive to the first storage controller being restored, the third storage device may be reassigned from the second storage controller to the first storage controller for load balancing at the first storage site during disaster recovery of the second storage site.

Abstract: One or more techniques and/or systems are provided for storage device health status synchronization. For example, a first health status registry is maintained for a first storage controller at a first storage site. The first storage controller stores storage device health status information of storage devices currently owned by or assigned to the first storage controller within the first health status registry. A second health status registry is maintained for a second storage controller at a second storage site. The second storage controller stores storage device health status information of storage device currently owned by or assigned to the second storage controller within the second health status registry. The first health status registry and the second health status registry are synchronized during operation of the first storage site and the second storage site and/or are merged between the first storage site and the second storage site after disaster recovery.

Abstract: In one aspect of the disclosure, progress identifiers (e.g., a plurality of flags) and/or generation numbers are utilized to determine a “correct” non-volatile random access memory (NVRAM) replay source to use during a retried switchover or early switchback. Initially, a switchover sequence is initiated. The switchover sequence includes a replay of logged information to storage devices of an aggregate to ensure data consistency of the aggregate. Progress of the switchover sequence is tracked using the progress identifiers and/or generation numbers. After an interruption during the switchover sequence, switchover is retried or an early switchback is performed. The retried switchover or early switchback decides whether to replay logged information, and, if so, determines an NVRAM replay source to replay logged information from based on states of the progress identifiers and/or comparison of the generation numbers.