Abstract: In some examples, a system includes a plurality of nodes connected to one or more networks, and each of the nodes may include at least one processor and one or more storage devices. The system may be configured to store data, and redundancy data for the data, across the plurality of nodes in the system based at least in part on a redundancy policy. Further, each of the nodes may maintain configuration information that indicates a data placement of the data and the redundancy data on the plurality of nodes. In addition, each of the nodes may be configured to have a function to act as a first node which is configured to determine, upon a change of the redundancy policy, updated configuration information for the system based on the change of the redundancy policy.

Abstract: A cluster system includes a plurality of computing nodes connected to a network, each node including one or more storage devices. The cluster system stores data and at least one of data replicas or erasure-coded segments across the plurality of nodes based on a redundancy policy. Further, configuration information, which may be indicative of a data placement of the data and the data replicas or erasure-coded segments on the plurality of nodes, is provided to each of the plurality of nodes. Additionally, each of the nodes may act as a first node which is configured to determine, upon a change of the redundancy policy, updated configuration information based on the change of the redundancy policy and to send a message including information indicating the change of the redundancy policy to the other nodes of the plurality of nodes.

Abstract: A cluster system includes a plurality of computing nodes connected to a network. Each node is configured to access its own storage device, and to send and receive input/output (I/O) operations associated with its own storage device. Further, each node of the plurality of nodes may be configured to have a function of acting as a first node, which sends a first message to other nodes of the plurality of nodes. The first message may include configuration information indicative of a data placement of data on the plurality of nodes in the cluster system according to an event. Following receipt of the first message from the first node, each of the other nodes may be configured to determine, based at least in part on the configuration information, whether data stored on its own storage device is affected by the event.

Abstract: Method and system is provided to perform a plurality of checks before performing a volume based snapshot restore (“VBSR”) operation. The checks may be performed by an application executed at a computing system that interfaces with a storage system. The application may determine if there are any inconsistent LUNS and foreign mapped LUNs. The application may also determine if there are any new LUNs or any new snapshots since the snapshot, which is the basis of the restore operation was created. The application may further determine if there are any backup relationships with respect to a volume that is being restored. The application takes the information and provides a report to a user. The report allows a user to ascertain the consequences of proceeding with the VBSR operation.

Abstract: A cluster system includes a plurality of computing nodes connected to a network, each node including one or more storage devices. The cluster system stores data and at least one of data replicas or erasure-coded segments across the plurality of nodes based on a redundancy policy. Further, configuration information, which may be indicative of a data placement of the data and the data replicas or erasure-coded segments on the plurality of nodes, is provided to each of the plurality of nodes. Additionally, each of the nodes may act as a first node which is configured to determine, upon a change of the redundancy policy, updated configuration information based on the change of the redundancy policy and to send a message including information indicating the change of the redundancy policy to the other nodes of the plurality of nodes.

Abstract: A cluster system includes a plurality of computing nodes connected to a network. Each node is configured to access its own storage device, and to send and receive input/output (I/O) operations associated with its own storage device. Further, each node of the plurality of nodes may be configured to have a function of acting as a first node, which sends a first message to other nodes of the plurality of nodes. The first message may include configuration information indicative of a data placement of data on the plurality of nodes in the cluster system according to an event. Following receipt of the first message from the first node, each of the other nodes may be configured to determine, based at least in part on the configuration information, whether data stored on its own storage device is affected by the event.

Abstract: A storage system includes a plurality of nodes connected to a network. Each node is capable of performing its own recovery of partially written data and maintaining consistency of the data stored on the storage system. The nodes may independently calculate the location of the data across the nodes and independently balance the data, maintain consistency based on a redundancy policy of the storage system, and migrate data according to a location change. If a node determines that the stored data thereon is incomplete or damaged, the node may reconstruct its respective data from replica data on other nodes. During migration of data between the nodes, I/O processing from a host is not interrupted in some examples.

Abstract: A storage system includes a plurality of nodes connected to a network. Each node is capable of performing its own recovery of partially written data and maintaining consistency of the data stored on the storage system. The nodes may independently calculate the location of the data across the nodes and independently balance the data, maintain consistency based on a redundancy policy of the storage system, and migrate data according to a location change. If a node determines that the stored data thereon is incomplete or damaged, the node may reconstruct its respective data from replica data on other nodes. During migration of data between the nodes, I/O processing from a host is not interrupted in some examples.

Abstract: A method, apparatus, and system of exclusive access during a critical sub-operation to enable simultaneous operations are disclosed. In one embodiment, a method of a host device includes identifying a critical sub-operation of an operation associated with a storage system, applying a lock associated with the critical sub-operation based on a type of the sub-operation, providing exclusive access of the critical sub-operation to a first instance requiring the critical sub-operation, denying other instances access to the critical sub-operation during an interval comprising a period when the first instance executes the critical sub-operation, and releasing the lock when the critical sub-operation is no longer required by the first instance. The first instance and the other instances may originate on different host devices.

Abstract: Method and system is provided to perform a plurality of checks before performing a volume based snapshot restore (“VBSR”) operation. The checks may be performed by an application executed at a computing system that interfaces with a storage system. The application may determine if there are any inconsistent LUNS and foreign mapped LUNs. The application may also determine if there are any new LUNs or any new snapshots since the snapshot, which is the basis of the restore operation was created. The application may further determine if there are any backup relationships with respect to a volume that is being restored. The application takes the information and provides a report to a user. The report allows a user to ascertain the consequences of proceeding with the VBSR operation.

Abstract: Method and system is provided to perform a plurality of checks before performing a volume based snapshot restore (“VBSR”) operation. The checks may be performed by an application executed at a computing system that interfaces with a storage system. The application may determine if there are any inconsistent LUNS and foreign mapped LUNs. The application may also determine if there are any new LUNs or any new snapshots since the snapshot, which is the basis of the restore operation was created. The application may further determine if there are any backup relationships with respect to a volume that is being restored. The application takes the information and provides a report to a user. The report allows a user to ascertain the consequences of proceeding with the VBSR operation.

Abstract: Techniques introduced herein allow writeable PPIs to be re-used. A writeable PPI manager can make use of existing writeable PPIs to offer logical units to clients without creating additional writeable PPIs. The writeable PPI manager can determine which writeable PPIs to re-use by testing the writeable PPIs for a variety of conditions. Advantageously, re-use of remaining logical units reduces unnecessary replication of data and increased overhead costs. Resources can thereby be conserved.

Abstract: According to one or more of the provisions set forth herein, data can be managed in a data storage system in an efficient manner. In one example, a first flexible copy volume of data is generated based on a snapshot copy volume of a flexible volume containing the data. The first flexible copy volume is configured to be operated upon according to a first set of operations. A second flexible copy of the data is also generated based on the snapshot copy volume. The second flexible copy volume is configured to be operated upon according to a second set of operations that differs from the first set of operations. Having a second copy of the data allows testing or other operations to be performed on the data while also maintaining an original version of the data.

Abstract: A method and system for generating authorization settings that indicate whether host administrators using a host-based storage-management application are authorized to perform provisioning operations on data storage entities residing on a data storage system are disclosed. Accordingly, a storage-management application receives from an administrator an authorization setting indicating on a per-user basis a set of provisioning operations which can be performed with a data storage entity via the storage-management application. The authorization settings are then communicated from the host-based storage-management application to the storage system where the data storage entity resides, and the authorization settings are stored. A storage-management application executing on any host can then utilize the authorization settings to control which users are allowed to interact with certain data storage entities, and what specific interactions (e.g., provisioning operations) are allowed.

Abstract: A method, apparatus, and system of exclusive access during a critical sub-operation to enable simultaneous operations are disclosed. In one embodiment, a method of a host device includes identifying a critical sub-operation of an operation associated with a storage system, applying a lock associated with the critical sub-operation based on a type of the sub-operation, providing exclusive access of the critical sub-operation to a first instance requiring the critical sub-operation, denying other instances access to the critical sub-operation during an interval comprising a period when the first instance executes the critical sub-operation, and releasing the lock when the critical sub-operation is no longer required by the first instance. The first instance and the other instances may originate on different host devices.

Abstract: Techniques introduced herein allow writeable PPIs to be analyzed prior to deletion to determine whether or not the writeable PPIs have reached the end of their life cycle. Prior to deletion a writeable PPI manager can inspect the writeable PPI to determine whether or not the writeable PPI has reached the end of the writeable PPI life cycle. If various criteria are not met, then the writeable PPI can be determined to have not yet reached the end of its life cycle and the deletion can be prevented.

Abstract: A method and system for generating authorization settings that indicate whether host administrators using a host-based storage-management application are authorized to perform provisioning operations on data storage entities residing on a data storage system are disclosed. Accordingly, a storage-management application receives from an administrator an authorization setting indicating on a per-user basis a set of provisioning operations which can be performed with a data storage entity via the storage-management application. The authorization settings are then communicated from the host-based storage-management application to the storage system where the data storage entity resides, and the authorization settings are stored. A storage-management application executing on any host can then utilize the authorization settings to control which users are allowed to interact with certain data storage entities, and what specific interactions (e.g., provisioning operations) are allowed.

Abstract: Information representing the RPC servers, on which each RPC service is currently being provided, is maintained on a directory server. A client may query the directory server and determine a specific one of the RPC servers on which to cause execution of a desired RPC service. Each RPC server may also register the service interface using which the corresponding RPC services can be accessed. As a result, the same RPC service may potentially be accessed with a different service interface on different RPC servers. Another aspect of the present invention provides a schema using which procedure interface definition (i.e., the name of the procedure, the parameters, and their attributes) can be represented. Such a feature is used to store the procedure definitions on the directory server, thereby enabling a client system to determine the procedure definition prior to sending an RPC request to execute the procedure.

Abstract: Information representing the RPC servers on which each RPC service is currently being provided, is maintained on a directory server. A client may query the directory server and determine a specific one of the RPC servers on which to cause execution of a desired RPC service. Each RPC server may also register the service interface using which the corresponding RPC services can be accessed. As a result, the same RPC service may potentially be accessed with a different service interface on different RPC servers. Another aspect of the present invention provides a schema using which procedure interface definition (i.e., the name of the procedure, the parameters and their attributes) can be represented. Such a feature is used to store the procedure definitions on the directory server, thereby enabling a client system to determine the procedure definition prior to sending an RPC request to execute the procedure.

Abstract: Information representing the RPC servers on which each RPC service is currently being provided, is maintained on a directory server. A client may query the directory server and determine a specific one of the RPC servers on which to cause execution of a desired RPC service. Each RPC server may also register the service interface using which the corresponding RPC services can be accessed. As a result, the same RPC service may potentially be accessed with a different service interface on different RPC servers. Another aspect of the present invention provides a schema using which procedure interface definition (i.e., the name of the procedure, the parameters and their attributes) can be represented. Such a feature is used to store the procedure definitions on the directory server, thereby enabling a client system to determine the procedure definition prior to sending an RPC request to execute the procedure.