Abstract: Embodiments are directed to error resistant logging. A write-ahead log (WAL) for preserving a verifiable record of file system activity may be provided such that the WAL may include a sequence of log blocks that each may include a cyclic redundancy check (CRC) value of a next adjacent log block in the WAL. In response to executing a file system operation associated with payload data, further actions may be performed, including: generating log blocks based on the payload data; generating a log segment that includes the log blocks; modifying a portion of the contents of a head-block of the log segment such that the modified head-block of the log segment has a CRC value that matches a CRC value of a tail-block of the WAL; copying the contents of the modified head-block of the log segment into the tail-block of the WAL.

Abstract: Embodiments are directed to managing data in a file system. An object from the file system that has parent objects may be provided. A snapshot in a current epoch may be generated such that the first snapshot may be based on the object and descendants of the object. A coverage set may be provided for the object that references the snapshot and also references each other snapshot that includes the parent objects. Read-only access to a version of the object may be provided based on a correspondence of the version and a snapshot referenced by the coverage set of the object. A coverage engine compares the update to a coverage update epoch (cue) associated with the parent objects. The coverage engine updates coverage sets of the parent objects based on grandparents of the object.

Abstract: Embodiments are directed to managing data in a file system that includes a plurality of storage nodes and a plurality of storage volumes such that each storage node may be a compute instance provided by a cloud computing environment (CCE) and each storage volume may be based on blobs provided by the CCE. Write requests that include write data may be provided. A lowest range of addresses in the storage volume may be determined for storing the write data. Buckets may be determined based on the range of addresses and the write data assigned to the buckets. If portions of the buckets remain unassigned, other data may be provided from a cache volume or the blobs. The write data and the other data may be written to the portion of the blobs.

Abstract: Embodiments are directed to a file system engine that provides a file system with parent objects associated with child objects. The file system engine provides a replication snapshot associated with an epoch of the file system such that each child object modified during the epoch and each associated parent object is associated with the replication snapshot. A root object of a portion of the file system included in the replication snapshot may be provided. A replication engine may traverse the portion of file system starting from the root object such that the parent objects that are not associated with the replication snapshot are omitted from the traversal. The replication engine may determine replication objects based on the traversal such that each replication object was modified during the epoch. Then the replication engine may execute a replication job that copies replication objects to a target file system.

Abstract: Embodiments are directed to file systems. A replication engine may establish a secure communication channel between a source file system and a target file system. The replication engine may: instantiate a replication job associated with rules; determine changes in the source file system; determine characteristics of the replication job that may be based on the changes; compare the to the characteristics and a black-out schedule; execute the replication job to communicate the changes in the source file system to the target file system based on a result of the comparison. Upon completion of the replication job, the replication engine may automatically instantiating a next replication job to copy subsequent changes in the source file system to the target file system.

Abstract: Embodiments are directed to managing data in a file system. An object from the file system that has parent objects may be provided. A snapshot in a current epoch may be generated such that the first snapshot may be based on the object and descendants of the object. A coverage set may be provided for the object that references the snapshot and also references each other snapshot that includes the parent objects. Read-only access to a version of the object may be provided based on a correspondence of the version and a snapshot referenced by the coverage set of the object. A coverage engine compares the update to a coverage update epoch (cue) associated with the parent objects. The coverage engine updates coverage sets of the parent objects based on grandparents of the object.

Abstract: Embodiments are directed to file systems. A replication engine may establish a secure communication channel between a source file system and a target file system. The replication engine may: instantiate a replication job associated with rules; determine changes in the source file system; determine characteristics of the replication job that may be based on the changes; compare the to the characteristics and a black-out schedule; execute the replication job to communicate the changes in the source file system to the target file system based on a result of the comparison. Upon completion of the replication job, the replication engine may automatically instantiating a next replication job to copy subsequent changes in the source file system to the target file system.

Abstract: Embodiments are directed to managing data in a file system. A file system engine provides a file system that includes file system objects that may be accessible by two or more clients that use different native permission schemes. And, a permissions engine may determine map rules based on characteristics of a request to access request a file. The permission engine may execute the one or more map rules to provide platform permission values based on the native permission values. The permission engine may compare requested platform permission values to the platform permission values associated with the file. The permission engine may provide the access rights to the file based on an affirmative result of the comparison.

Abstract: Embodiments are directed to file systems. A replication engine may establish a secure communication channel between a source file system and a target file system. The replication engine may: instantiate a replication job associated with rules; determine changes in the source file system; determine characteristics of the replication job that may be based on the changes; compare the to the characteristics and a black-out schedule; execute the replication job to communicate the changes in the source file system to the target file system based on a result of the comparison. Upon completion of the replication job, the replication engine may automatically instantiating a next replication job to copy subsequent changes in the source file system to the target file system.