Abstract: Systems and methods for flushing an operation log journal to both ephemeral storage and persistent storage during a shutdown sequence of a virtual storage system to minimize data-loss scenarios are provided. According to one embodiment, the shutdown or reboot scenarios that result in loss of data are minimized by using persistent storage as a backup to ephemeral storage when the scenario results in rehosting of virtual storage system. For example, responsive to an event indicative of an imminent shutdown or reboot of the virtual storage system, vNVRAM memory may be flushed to both ephemeral storage and persistent storage (e.g., a boot disk). In this manner, when the virtual storage system is rehosted after an unplanned shutdown or reboot resulting from an unrecoverable host error (other than an unrecoverable hardware failure), the operation log journal may be recovered from persistent storage to facilitate vNVRAM replay and avoid data loss.

Abstract: Systems and methods for making use of non-persistent storage as the journaling storage media for a virtual storage system are provided. According to one embodiment, in order to meet the needs of Extreme Low Latency Workloads while also seeking to provide predictable performance and the lowest possible latency, ephemeral storage of the virtual storage system is used to preserve state information (e.g., in the form of boot arguments and an operation log journal) across a host failure recovery scenario in which the virtual storage system is expected to be redeployed within a compute instance brought up by a cloud environment of a hyperscaler on the same host, thereby providing improved data durability (fewer host failure scenarios that result in lost data) as compared to the use of ephemeral memory of the compute instance and lower write latency than the use of persistent storage provided by the cloud environment.

Abstract: Systems and methods for facilitating performance of data tiering by detecting and persisting types of backing storage of cloud volumes that are available for use by a virtual storage system are provided. In one example, during a boot phase of the virtual storage system within a compute instance of a cloud environment, information regarding a type of backing storage for each of multiple storage devices associated with the compute instance that is not available via hypervisor APIs is obtained via an API exposed by the cloud environment. The multiple storage devices may then be initialized to facilitate subsequent use of a subset thereof in connection with performing data tiering by persisting information indicative of the type of backing storage for the storage device within a reserved header region on each storage device.

Abstract: Systems and methods for making use of non-persistent storage as the journaling storage media for a virtual storage system are provided. According to one embodiment, in order to meet the needs of Extreme Low Latency Workloads while also seeking to provide predictable performance and the lowest possible latency, ephemeral storage of the virtual storage system is used to preserve state information (e.g., in the form of boot arguments and an operation log journal) across a host failure recovery scenario in which the virtual storage system is expected to be redeployed within a compute instance brought up by a cloud environment of a hyperscaler on the same host, thereby providing improved data durability (fewer host failure scenarios that result in lost data) as compared to the use of ephemeral memory of the compute instance and lower write latency than the use of persistent storage provided by the cloud environment.

Abstract: Systems and methods for facilitating performance of data tiering by detecting and persisting types of backing storage of cloud volumes that are available for use by a virtual storage system are provided. In one example, during a boot phase of the virtual storage system within a compute instance of a cloud environment, information regarding a type of backing storage for each of multiple storage devices associated with the compute instance that is not available via hypervisor APIs is obtained via an API exposed by the cloud environment. The multiple storage devices may then be initialized to facilitate subsequent use of a subset thereof in connection with performing data tiering by persisting information indicative of the type of backing storage for the storage device within a reserved header region on each storage device.

Abstract: Systems and methods for making use of non-persistent storage as the journaling storage media for a virtual storage system are provided. According to one embodiment, in order to meet the needs of Extreme Low Latency Workloads while also seeking to provide predictable performance and the lowest possible latency, ephemeral storage of the virtual storage system is used to preserve state information (e.g., in the form of boot arguments and an operation log journal) across a host failure recovery scenario in which the virtual storage system is expected to be redeployed within a compute instance brought up by a cloud environment of a hyperscaler on the same host, thereby providing improved data durability (fewer host failure scenarios that result in lost data) as compared to the use of ephemeral memory of the compute instance and lower write latency than the use of persistent storage provided by the cloud environment.

Abstract: Systems and methods for flushing an operation log journal to both ephemeral storage and persistent storage during a shutdown sequence of a virtual storage system to minimize data-loss scenarios are provided. According to one embodiment, the shutdown or reboot scenarios that result in loss of data are minimized by using persistent storage as a backup to ephemeral storage when the scenario results in rehosting of virtual storage system. For example, responsive to an event indicative of an imminent shutdown or reboot of the virtual storage system, vNVRAM memory may be flushed to both ephemeral storage and persistent storage (e.g., a boot disk). In this manner, when the virtual storage system is rehosted after an unplanned shutdown or reboot resulting from an unrecoverable host error (other than an unrecoverable hardware failure), the operation log journal may be recovered from persistent storage to facilitate vNVRAM replay and avoid data loss.

Abstract: Systems and methods for making use of non-persistent storage as the journaling storage media for a virtual storage system are provided. According to one embodiment, in order to meet the needs of Extreme Low Latency Workloads while also seeking to provide predictable performance and the lowest possible latency, ephemeral storage of the virtual storage system is used to preserve state information (e.g., in the form of boot arguments and an operation log journal) across a host failure recovery scenario in which the virtual storage system is expected to be redeployed within a compute instance brought up by a cloud environment of a hyperscaler on the same host, thereby providing improved data durability (fewer host failure scenarios that result in lost data) as compared to the use of ephemeral memory of the compute instance and lower write latency than the use of persistent storage provided by the cloud environment.

Abstract: A method for sharing a storage device amongst a plurality of computers while providing data integrity in the storage device is presented. A computer is registered for a reserved access type with the storage device by storing a computer identifier in the storage device. Access to the storage device is provided to the registered computer dependent on the registered computer's stored identifier and the reserved access type. Upon loss of knowledge of the stored identifier in the shared storage device by the registered computer, the computer replaces the previous identifier for the computer stored in the shared storage device with a new identifier. The registered computer may be a currently registered computer or a previously registered computer.

Abstract: A method for sharing a storage device amongst a plurality of computers while providing data integrity in the storage device is presented. A computer is registered for a reserved access type with the storage device by storing a computer identifier in the storage device. Access to the storage device is provided to the registered computer dependent on the registered computer's stored identifier and the reserved access type. Upon loss of knowledge of the stored identifier in the shared storage device by the registered computer, the computer replaces the previous identifier for the computer stored in the shared storage device with a new identifier. The registered computer may be a currently registered computer or a previously registered computer.

Abstract: A method for sharing a storage device amongst a plurality of computers while providing data integrity in the storage device is presented. A computer is registered for a reserved access type with the storage device by storing a computer identifier in the storage device. Access to the storage device is provided to the registered computer dependent on the registered computer's stored identifier and the reserved access type. Upon loss of knowledge of the stored identifier in the shared storage device by the registered computer, the computer replaces the previous identifier for the computer stored in the shared storage device with a new identifier. The registered computer may be a currently registered computer or a previously registered computer.