Abstract: Systems and methods are provided for replication sequencing and state management in a distributed storage system. A storage system may receive, from a remote storage system, a request to replicate first tag data for a data object replicated from the remote storage system to the storage system, wherein the first tag data is associated with a request sequence identifier; evaluate an object marker in object metadata for the data object, the object marker comprising an object marker sequence identifier associated with replication of second tag data previously stored for the data object; determine, based on an analysis of the request sequence identifier and the object marker sequence identifier, whether to replace the second tag data with the first tag data, wherein tag data replacement is prohibited if the object marker sequence identifier is after the request sequence identifier; and perform a storage operation associated with the data object.

Abstract: Systems and methods are provided for durable asynchronous replication in a distributed storage system. A storage system may commit a transaction comprising saving a data object to a persistent object storage location and saving a replication marker to a first persistent storage directory for pending replication tasks, wherein the replication marker comprises replication data for replicating the data object to a remote storage system, and wherein the first persistent storage directory comprises a replication queue; determine, based on a presence of the replication marker in the first persistent storage directory, to dequeue the replication marker from the replication queue; move the replication marker to a second persistent storage directory for in-process replication tasks; attempt replication of the data object to the remote storage system; and move the replication marker to a third persistent storage directory.

Abstract: A test application programming interface (API) request may be issued to a test service implementation. A test API response, which is responsive to the test API request, may be received from the test service implementation. First contents of the test API response may be compared to second contents of a control API response. The comparing may be performed based at least in part on a set of one or more expected differences associated with the test API response and the control API response. It may be determined, based on the comparing, whether an unexpected difference exists between the test API response and the control API response. An indication may be provided of whether the unexpected difference exists between the test API response and the control API response, and the unexpected difference may be automatically corrected, such as via one or more configuration changes.