Abstract: Efficient authentication in a file system with multiple security groups is disclosed. A file system (FS) executing on at least one processor device receives, from a first client application of a plurality of client applications, a request to access a first object, the request including a unique object ID that identifies the first object. The FS determines, based on a data structure maintained by the FS and inaccessible to the first client application, that the first client application is associated with a first security group of a plurality of different security groups. The FS determines, based on metadata of the first object, that the first object is associated with the first security group, and grants the first client application access to the first object.

Abstract: Systems and methods for enforcing consistency of file to storage node mappings in distributed file systems. An example method may include: receiving a request to perform a file operation with respect to a file associated with a directory of a distributed file system; identifying a directory layout version number associated with the directory; identifying a volume layout version number associated with a volume in which the directory resides; and responsive to determining that the directory layout version number matches the volume layout version number, performing the requested file operation with respect to the file.

Abstract: Systems and methods for reducing locks on a storage layout of a distributed file system by detecting and notifying clients of stale storage layouts. An example method may comprise: receiving a request to modify a file system object associated with a storage layout, the request comprising an index range and the storage layout comprising an index range; determining whether the request is associated with a stale storage layout in view of a comparison of the index range of the request and the one or more index ranges of the storage layout; receiving a lock request to prevent changes to the storage layout; and transmitting at least a portion of the storage layout to update the stale storage layout.

Abstract: Systems and methods for reducing locks on a storage layout of a distributed file system by detecting and notifying clients of stale storage layouts. An example method may comprise: receiving a request to modify a file system object associated with a storage layout, the request comprising an index range and the storage layout comprising an index range; determining whether the request is associated with a stale storage layout in view of a comparison of the index range of the request and the one or more index ranges of the storage layout; receiving a lock request to prevent changes to the storage layout; and transmitting at least a portion of the storage layout to update the stale storage layout.

Abstract: Systems and methods for allocating file system metadata to storage nodes of a distributed file system. An example method may include: defining, by a processing device, a plurality of tokens, wherein each token comprises a sequence of bits; associating each token of the plurality of tokens with a metadata node of a cluster of metadata nodes; receiving a request to create a directory; selecting, among the plurality of tokens, a token associated with the directory; generating a directory identifier comprising the selected token; and creating, on a metadata node associated with the selected token, a directory record comprising the directory identifier.

Abstract: Systems and methods for enforcing consistency of file to storage node mappings in distributed file systems. An example method may include: receiving a request to perform a file operation with respect to a file associated with a directory of a distributed file system; identifying a directory layout version number associated with the directory; identifying a volume layout version number associated with a volume in which the directory resides; and responsive to determining that the directory layout version number matches the volume layout version number, performing the requested file operation with respect to the file.

Abstract: Efficient authentication in a file system with multiple security groups is disclosed. A file system (FS) executing on at least one processor device receives, from a first client application of a plurality of client applications, a request to access a first object, the request including a unique object ID that identifies the first object. The FS determines, based on a data structure maintained by the FS and inaccessible to the first client application, that the first client application is associated with a first security group of a plurality of different security groups. The FS determines, based on metadata of the first object, that the first object is associated with the first security group, and grants the first client application access to the first object.

Abstract: Systems and methods for enforcing consistency of file to storage node mappings in distributed file systems. An example method may include: receiving a request to perform a file operation with respect to a file associated with a volume of a distributed file system; identifying, among a plurality of storage nodes of the distributed file system, a storage node associated with the file; obtaining a lock of a layout of the volume; and responsive to determining, by a processing device, that a directory layout version number matches a volume layout version number, performing the requested file operation with respect to the file.

Abstract: Systems and methods for reducing locks on a storage layout of a distributed file system by detecting and notifying clients of stale storage layouts. An example method may comprise: receiving a request to modify a file system object associated with a storage layout, the request comprising an index range and the storage layout comprising an index range; determining whether the request is associated with a stale storage layout in view of a comparison of the index range of the request and the one or more index ranges of the storage layout; receiving a lock request to prevent changes to the storage layout; and transmitting at least a portion of the storage layout to update the stale storage layout.

Abstract: Systems and methods for enforcing consistency of file to storage node mappings in distributed file systems. An example method may include: receiving a request to perform a file operation with respect to a file associated with a volume of a distributed file system; identifying, among a plurality of storage nodes of the distributed file system, a storage node associated with the file; obtaining a lock of a layout of the volume; and responsive to determining, by a processing device, that a directory layout version number matches a volume layout version number, performing the requested file operation with respect to the file.

Abstract: Systems and methods for allocating file system metadata to storage nodes of a distributed file system. An example method may include: defining, by a processing device, a plurality of tokens, wherein each token comprises a sequence of bits; associating each token of the plurality of tokens with a metadata node of a cluster of metadata nodes; receiving a request to create a directory; selecting, among the plurality of tokens, a token associated with the directory; generating a directory identifier comprising the selected token; and creating, on a metadata node associated with the selected token, a directory record comprising the directory identifier.

Abstract: Techniques for achieving tenant data confidentiality in a cloud environment are presented. A daemon process within a Tenant Storage Machine (TSM) manages a key store for a particular tenant of a cloud storage environment having multiple other tenants. Just TSM storage processes are given access to the key store. Data is decrypted for the particular tenant when access is needed and data is encrypted using encryption keys of the key store when written in the cloud storage environment.

Abstract: Techniques for translating Service Level Agreement (SLA) policy into storage controller requirements within a cloud storage environment are presented. System resource metrics for a storage controller are derived. The SLA policy is defined in terms of SLA parameters. Heuristics are used to translate the SLA parameters into defined percentages of system resources for the storage controller, which are compared to the system resource metrics and adjustments are updates are made as needed.

Abstract: Techniques for translating Service Level Agreement (SLA) policy into storage controller requirements within a cloud storage environment are presented. System resource metrics for a storage controller are derived. The SLA policy is defined in terms of SLA parameters. Heuristics are used to translate the SLA parameters into defined percentages of system resources for the storage controller, which are compared to the system resource metrics and adjustments are updates are made as needed.

Abstract: Techniques for achieving tenant data confidentiality in a cloud environment are presented. A daemon process within a Tenant Storage Machine (TSM) manages a key store for a particular tenant of a cloud storage environment having multiple other tenants. Just TSM storage processes are given access to the key store. Data is decrypted for the particular tenant when access is needed and data is encrypted using encryption keys of the key store when written in the cloud storage environment.

Abstract: Techniques for the session sensitive data backups and restores are presented. Data having a plurality of hard linked file references are backed up and restored once during a backup operation. Any modifications to the backed up data are noted as session-specific versions and also backed up once. The hard linked file references are maintained in a data structure and managed during backups to define associations to the backed up data and to the session-specific versions of the data. The data structure is also used during restores to re-establish desired hard linked file reference associations to either the backed up data or to a particular session-specific versions of the data.

Abstract: Techniques for the session sensitive data backups and restores are presented. Data having a plurality of hard linked file references are backed up and restored once during a backup operation. Any modifications to the backed up data are noted as session-specific versions and also backed up once. The hard linked file references are maintained in a data structure and managed during backups to define associations to the backed up data and to the session-specific versions of the data. The data structure is also used during restores to re-establish desired hard linked file reference associations to either the backed up data or to a particular session -specific versions of the data.

Abstract: Techniques for data replication are presented. A snap shot request is processed within an environment associated with a local volume by flushing pending Input/Output (I/O) operations into an event packet. The event packet is sent to a replicated volume and processed against the replicated volume to create a snap shot version of the local volume.

Abstract: Techniques for asynchronous data replication are presented. A bitmap records changes to selective blocks of data on a source between replication periods. During a replication, the bitmap is copied and used to acquire changed blocks from the source to write to a replica. Should a unprocessed block have a pending write detected during the replication, then that block is copied into cache from the source before the write is processed on the source. The pending write then processes against the source; the copied block is flushed to the replica; the original bitmap and copied bitmap are updated.

Abstract: Techniques for data replication are presented. A snap shot request is processed within an environment associated with a local volume by flushing pending Input/Output (I/O) operations into an event packet. The event packet is sent to a replicated volume and processed against the replicated volume to create a snap shot version of the local volume.