1. A method for collecting and aggregating datasets for storage in a file system with fault tolerance, the method comprising: collecting datasets from a data source on a machine where the datasets are generated; generating a batch comprising multiple messages from the datasets; assigning a tag to the batch and computing a checksum for the batch; writing the tag, the batch of multiple messages, and the checksum to an entry in a write-ahead-log (WAL) in storage; sending the datasets to a receiving location; in response to verifying the checksum of the batch of multiple messages at the receiving location, adding the tag to a map; writing a file to destination location; and identifying, in the file, tags associated with the batches in the file that have been written to the destination location.