When a Clientthat uses aliased Nodesdetects a communication problem with the Server, the Clientcan return to the GDS and request a new AliasNodeListfor the AliasName. The original Servermay recover and again be listed in the GDS, but the Clientis not required to switch back. Figure B-11provides an overview of this process.


Figure B-11– Example Client Process for Server subscription with errors

It is important to remember that the FindAlias Methodwill return a list of NodeIds(and Servers) that meet the requested AliasNamesearch string. It is up to the Clientto determine if the NodeIdthat is returned is the same Serveror on a different Serveror if the next NodeIdshould be used instead of the first.


ANSI/ISA-S5.1-1984 (R 1992), Instrumentation Symbols and Identification