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vrdb(5)								       vrdb(5)

NAME

vrdb - Volume Replication Data Base specification

DESCRIPTION

The volume replication data base is stored in binary form in /vice/db/VRDB on each file server. The makevrdb option of the volu- til(8) program constructs the VRDB on the system control machine (SCM). The data base consists of fixed-length records, each of which describes a replicated (aka group) volume. Each file server copies the VRDB into memory at start-up and whenever an updated version of it is received. The data base is used to map group volume names and numbers into a VSG and the set of read-write volumes which comprise it. The VRDB is generated from an ASCII version stored on the SCM in /vice/vol/VRList. The VRList is updated as a side-effect of every cre- ate and purge of a replicated volume. Its format is: <group volname> <group volnum> <# of replicas> <rwvol 1> ... <rwvol 8> <VSG num> A sample line from the VRList is: project.coda.src 7f000010 3 c9000012 ca000013 cb000013 0 0 0 0 0 E0000107 Note that all volume and VSG numbers are given in hex. Details of the VRDB structure can be found in <vrdb.h>.

FILES

/vice/db/VRDB /vice/vol/VRList

BUGS

File servers keep the in-memory copy as a singly-linked list. It should be converted to a pair of hash-tables, one keyed by group vol- name, the other by group volnum, for fast lookup. The maximum number of replication sites is fixed at 8. Adding, delet- ing, or moving replication sites after creation is not supported.

SEE ALSO

volutil (8), maxgroupid (5), vsgdb (5)

AUTHOR

Jay Kistler, 1990, created vrdb(5)

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