Object service receives request to copy file to destination and identifies group identifier for fingerprints group corresponding to sequential segments in file. Object service communicates request for fingerprints group to deduplication service associated with group identifier range including group identifier. Deduplication service communicates fingerprints group, retrieved from fingerprint storage, to object service, which communicates fingerprints group and group identifier to destination. Object service communicates request for file segments, corresponding to fingerprints missing in destination, communicated from destination, to deduplication service, which communicates requested segments, retrieved from source storage, to object service, which communicates requested segments to destination. System identifies generation identifier associated with time of communicating by object service or deduplication service, and generation identifier associated with another time of communicating by object service or deduplication service. If generation identifier associated with time differs from generation identifier associated with other time, object service or deduplication service restarts communication.