HCoop / hcoop / debian / openafs.git / blame
| Commit | Line | Data |
|---|---|---|
| 805e021f CE |
1 | =head1 NAME |
| 2 | ||
| 3 | vldb.DB0, vldb.DBSYS1 - Contain the Volume Location Database and associated log | |
| 4 | ||
| 5 | =head1 DESCRIPTION | |
| 6 | ||
| 7 | The file F<vldb.DB0> contains the Volume Location Database (VLDB), which | |
| 8 | tracks the location of all AFS volumes stored on file server machines in | |
| 9 | the cell. The Volume Location (VL) Server (B<vlserver> process) provides | |
| 10 | information from the database to Cache Managers when they need to access | |
| 11 | AFS data. | |
| 12 | ||
| 13 | The file F<vldb.DBSYS1> is a log file in which the VL Server logs each | |
| 14 | database operation before performing it. When an operation is interrupted, | |
| 15 | the VL Server replays the log to complete the operation. | |
| 16 | ||
| 17 | Both files are in binary format and reside in the F</usr/afs/db> directory | |
| 18 | on each of the cell's database server machines. When the VL Server starts | |
| 19 | or restarts on a given machine, it establishes a connection with its peers | |
| 20 | and verifies that its copy of the database matches the copy on the other | |
| 21 | database server machines. If not, the VL Servers call on AFS's distributed | |
| 22 | database technology, Ubik, to distribute to all of the machines the copy | |
| 23 | of the database with the highest version number. | |
| 24 | ||
| 25 | Always use the commands in the B<vos> suite to administer the VLDB. It is | |
| 26 | advisable to create an archive copy of the database on a regular basis, | |
| 27 | using a tool such as the UNIX B<tar> command. | |
| 28 | ||
| 29 | =head1 SEE ALSO | |
| 30 | ||
| 31 | L<vldb_check(8)>, | |
| 32 | L<vlserver(8)>, | |
| 33 | L<vos(1)> | |
| 34 | ||
| 35 | =head1 COPYRIGHT | |
| 36 | ||
| 37 | IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved. | |
| 38 | ||
| 39 | This documentation is covered by the IBM Public License Version 1.0. It was | |
| 40 | converted from HTML to POD by software written by Chas Williams and Russ | |
| 41 | Allbery, based on work by Alf Wachsmann and Elizabeth Cassell. |