release notes | Book: 2.10, 2.11, 2.12, 2.13, 2.14 | Wiki | Q&A black_bg
Web: Multi-page, Single page | PDF: A4-size, Letter-size | eBook: epub black_bg

Chapter 6. The replica Service (Replica Manager)

The replica service (which is also referred to as Replica Manager) controls the number of replicas of a file on the pools. If no tertiary storage system is connected to a dCache instance (i.e., it is configured as a large file store), there might be only one copy of each file on disk. (At least the precious replica.) If a higher security and/or availability is required, the resilience feature of dCache can be used: If running in the default configuration, the replica service will make sure that the number of replicas of a file will be at least 2 and not more than 3. If only one replica is present it will be copied to another pool by a pool to pool transfer. If four or more replicas exist, some of them will be deleted.