Abstract: Techniques are described for enabling concurrent cross-region replications and garbage collection while maintaining consistency and data integrity among file systems. In some embodiments, techniques for garbage collection fencing utilize a system-level garbage fencing key (GC fencing key) and one or more job-level GC fencing keys in a source file system that perform one or more cross-region replications with one or more target file systems, one replication and one job-level GC fencing key per target file system. In some embodiments, one job-level GC fencing key in a source file system and one job-level GC fencing key in a source file system together provide garbage fencing for a cross-region replication. In certain embodiments, the metadata information in a GC fencing key can inform, instruct, or be used to configure garbage collectors to skip garbage collection for a range of snapshots in a file system.

Abstract: Novel techniques are described for maintaining file consistency between different cloud infrastructure regions during cross-region file storage replication. The novel techniques comprise upon detecting a file deletion status (i.e., a file directory entry version marked as deletion) in a source file system during a replication cycle, retrieving file name from a valid file directory entry of a prior snapshot to construct a temporary file directory entry containing necessary information for a target file system to reconstruct a duplicate file directory entry version marked as deletion. The temporary file directory entry is transferred from the source file system to the target file system during the same replication cycle.