The Fileset Location Database (FLDB) is maintained by the FL Server. The FLDB records information about the locations of the filesets in a cell. Users do not need to know the location of a fileset to access it; the Cache Manager contacts the FL Server to obtain the location of a requested fileset.
Each read/write fileset has an entry in the FLDB; the entry includes information about the fileset's read-only and backup versions. Read-only and backup filesets normally do not have their own FLDB entries because they share an FLDB entry with the read/write fileset. However, a read-only fileset can have its own entry if its read/write source is removed.
For a DCE LFS fileset, information is also stored in the fileset's header, which is part of the data structure that records the physical addresses on the aggregate of the files in the fileset. It is essential that the FLDB entry and the fileset header be synchronized (that they match). Therefore, all fts commands that affect fileset status and the FLDB change both the appropriate FLDB entry and the fileset header. In some rare cases, however, you may need to resynchronize the entries yourself (see Managing Filesets).
A non-LFS fileset does not have a fileset header, but some information about the fileset is available from the local disk of the machine on which it resides. For example, the fileset ID number of each non-LFS fileset is stored in the dcelocal/var/dfs/dfstab on the local machine. (See Exporting Aggregates and Partitions for a description of the dfstab file.)
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A Fileset's Header Information