Abstract: One or more techniques and/or systems are provided for controlling restoration of a storage aggregate. For example, a local storage device, located at a first storage site, and a remote storage device, located at a second storage site, may be assigned to a first storage aggregate. Responsive to a disaster of the first storage site, a gate may be created for the local storage device. The gate may block automated reconstruction and/or automated synchronization that may otherwise occur with respect to the local storage device. Until the local storage device is restored, the remote storage device may be used to service I/O requests that were otherwise directed to the local storage device. Responsive to receiving a user restoration command, the gate may be removed from the local storage device. Synchronization between the local storage device and the remote storage device may then be facilitated.

Abstract: One or more techniques and/or systems are provided for mirror vote synchronization. For example, a first storage device is located at a first storage site, and a second storage device is located at a second storage site. The second storage device is configured according to a data mirroring configuration where data from the first storage device is mirrored to the second storage device. Mirror vote metadata is generated based upon an up-to-date state of the data mirroring configuration. The mirror vote metadata indicates whether the first storage device and/or the second storage device are up-to-date or not. The mirror vote metadata may be replicated between the first storage site and the second storage site. If the first storage site fails, then the second storage site may provide switchover operation using the second storage device based upon the mirror vote metadata.

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 controlling restoration of a storage aggregate. For example, a local storage device, located at a first storage site, and a remote storage device, located at a second storage site, may be assigned to a first storage aggregate. Responsive to a disaster of the first storage site, a gate may be created for the local storage device. The gate may block automated reconstruction and/or automated synchronization that may otherwise occur with respect to the local storage device. Until the local storage device is restored, the remote storage device may be used to service I/O requests that were otherwise directed to the local storage device. Responsive to receiving a user restoration command, the gate may be removed from the local storage device. Synchronization between the local storage device and the remote storage device may then be facilitated.

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 controlling restoration of a storage aggregate. For example, a local storage device, located at a first storage site, and a remote storage device, located at a second storage site, may be assigned to a first storage aggregate. Responsive to a disaster of the first storage site, a gate may be created for the local storage device. The gate may block automated reconstruction and/or automated synchronization that may otherwise occur with respect to the local storage device. Until the local storage device is restored, the remote storage device may be used to service I/O requests that were otherwise directed to the local storage device. Responsive to receiving a user restoration command, the gate may be removed from the local storage device. Synchronization between the local storage device and the remote storage device may then be facilitated.

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 mirror vote synchronization. For example, a first storage device is located at a first storage site, and a second storage device is located at a second storage site. The second storage device is configured according to a data mirroring configuration where data from the first storage device is mirrored to the second storage device. Mirror vote metadata is generated based upon an up-to-date state of the data mirroring configuration. The mirror vote metadata indicates whether the first storage device and/or the second storage device are up-to-date or not. The mirror vote metadata may be replicated between the first storage site and the second storage site. If the first storage site fails, then the second storage site may provide switchover operation using the second storage device based upon the mirror vote metadata.

Abstract: One or more techniques and/or systems are provided for mirror vote synchronization. For example, a first storage device is located at a first storage site, and a second storage device is located at a second storage site. The second storage device is configured according to a data mirroring configuration where data from the first storage device is mirrored to the second storage device. Mirror vote metadata is generated based upon an up-to-date state of the data mirroring configuration. The mirror vote metadata indicates whether the first storage device and/or the second storage device are up-to-date or not. The mirror vote metadata may be replicated between the first storage site and the second storage site. If the first storage site fails, then the second storage site may provide switchover operation using the second storage device based upon the mirror vote metadata.

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 controlling restoration of a storage aggregate. For example, a local storage device, located at a first storage site, and a remote storage device, located at a second storage site, may be assigned to a first storage aggregate. Responsive to a disaster of the first storage site, a gate may be created for the local storage device. The gate may block automated reconstruction and/or automated synchronization that may otherwise occur with respect to the local storage device. Until the local storage device is restored, the remote storage device may be used to service I/O requests that were otherwise directed to the local storage device. Responsive to receiving a user restoration command, the gate may be removed from the local storage device. Synchronization between the local storage device and the remote storage device may then be facilitated.

Abstract: One or more techniques and/or systems are provided for controlling restoration of a storage aggregate. For example, a local storage device, located at a first storage site, and a remote storage device, located at a second storage site, may be assigned to a first storage aggregate. Responsive to a disaster of the first storage site, a gate may be created for the local storage device. The gate may block automated reconstruction and/or automated synchronization that may otherwise occur with respect to the local storage device. Until the local storage device is restored, the remote storage device may be used to service I/O requests that were otherwise directed to the local storage device. Responsive to receiving a user restoration command, the gate may be removed from the local storage device. Synchronization between the local storage device and the remote storage device may then be facilitated.

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 mirror vote synchronization. For example, a first storage device is located at a first storage site, and a second storage device is located at a second storage site. The second storage device is configured according to a data mirroring configuration where data from the first storage device is mirrored to the second storage device. Mirror vote metadata is generated based upon an up-to-date state of the data mirroring configuration. The mirror vote metadata indicates whether the first storage device and/or the second storage device are up-to-date or not. The mirror vote metadata may be replicated between the first storage site and the second storage site. If the first storage site fails, then the second storage site may provide switchover operation using the second storage device based upon the mirror vote metadata.

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 mirror vote synchronization. For example, a first storage device is located at a first storage site, and a second storage device is located at a second storage site. The second storage device is configured according to a data mirroring configuration where data from the first storage device is mirrored to the second storage device. Mirror vote metadata is generated based upon an up-to-date state of the data mirroring configuration. The mirror vote metadata indicates whether the first storage device and/or the second storage device are up-to-date or not. The mirror vote metadata may be replicated between the first storage site and the second storage site. If the first storage site fails, then the second storage site may provide switchover operation using the second storage device based upon the mirror vote metadata.

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.