Questions about LabVIEW

[niOregon]

Dear support team,

Could someone please respond to Eric's questions? Eric works at Bonneville Power Administration and they are gearing up for another major LabVIEW and DSC project. He may have LabVIEW 7 beta. I am on my way out of town for two weeks and won't have access to phone or email. Thanks!!

Tricia Lee
DSM Inland Northwest
tricia.lee@ni.com


"Pierce, Eric - TNCB-TPP-2"
05/01/2003 08:05 AM

To: tricia.lee@ni.com
cc:
Subject: The list of question i never sent


Sorry for the long delay, things have been very busy here with this new project. I have questions / concerns about the DSC, OPC and LOGOS; first here is our architecture.

We will have two servers running windows 2000 server. Both servers will be live and need to have all DSC components installed. One server is to act as the primary server and the second is to act as a failover server. We have custom components that manage all of our custom services, if one of the custom services stops responding the failover service will shut down all custom services on the primary server and start all of the custom services on the secondary server, thus, the secondary server becomes our primary live server.

My understanding is that we will have to load a *.spf file on each HMI that tells the HMI where the server is, at the same time we need to initialize the DSC and OPC with *spf and *.lpd files. Now I might have the file extensions wrong but the idea is the same. We have all of our data in a SQL 2000 database, how do we make sure that all of the configuration files match the SQL 2000 db? We have several GUI's that can edit the SQL 2000 data, how do we update the DSC / OPC configuration files?

So in short here are my current questions:
How can we manage failover with two live servers
How can we ensure that DSC / OPC / Logos configuration files match the data in SQL 2000?

Does any of this make sense? This labview stuff is very new to me.


Eric Pierce
ACS Group, Inc.
Sr. Software Engineer
w. (360) 619-6284

[Khalid]

Hi Eric,

You got it right that once the primary machine goes down, the standby machine detects this, and then loads the appropriate SCF file, etc. Caveat: This would mean however that the hardware in question is accessible by both the machines (it's on an Ethernet, for instance). Any hardware physically connected to the primary machine will obviously be not accessible by the secondary (unless there's a way to have a "Y" connection).

The logging part you mention is not very clear to me. Several questions come to mind: Isn't DSC the logger, logging to its Citadel database? Or, is SQL 2000 the main database? And DSC is logging to SQL 2000? If yes, how? Or is the SQL 2000 querying Citadel and hence getting the data into itself?

Regards,


Khalid 🙂