This page applies to Multiple Resilience Configurations Only
This section describes the use of the 'local' flag and its interaction with the location override flag.
The location information for a table stored on the database is as follows:
A flag in the @RELDATA entry for the table, which can be set to either 'local' or 'remote' using MAKEDB -expert. This flag is used in both local resilience and multiple resilience configurations.
Optionally, and for multiple resilience only, a persistent entry in the @NETWORK table giving a list of server numbers for the table.
When an application first accesses a
particular table, AUXDISTR creates an in-memory copy of an @NETWORK
table entry for that table as follows: the list of server numbers
is copied from the entry on the database, if there is one, and
otherwise is taken from the list of default servers supplied by
command tails. The network.local flag is
copied from the @RELDATA table entry (unless
the −nolocal command tail is used on AUXDISTR, in which case network.local will be set to No). The value of local contained in any persistent @network record for the table is ignored.
Subsequently this in-memory copy of the @NETWORK table entry is used to determine which servers to use whenever the table is accessed.
rec_post() and rec_kill()operations on the @NETWORK table operate exclusively on the in-memory copy of the table and are not passed on to the database. Posting to @NETWORK can change the list of server numbers and the 'local' flag. Deleting from @NETWORK causes the original default entry to be restored.
AUXDISTR determines which servers to use for an operation on a database table as follows:
network.local field is temporarily reversed.
network.local field is
TRUE the local server is used; otherwise the servers in the list
are used.