Network OPC Modbus TCP/IP / SQL trouble after deploying variables/process (DSC) Same software runs well for one months before

[computerkammer]

Hello,

I need help with a curious problem. Unfortunately I don't have any ideas where I can start to debug the mistake.

I wrote an application on LabVIEW 8.5 + DSC where the DSC integrated Modbus TCP/IP + OPC-Client is used. The data are acquired over 2 different Ethernet card in different subnets.

Some values are stored on a full version of MS SQL-Workstation 2005.

Here is my problem:

The first version runs since one months without any trouble. Last week I wanted to make an update. The software run well. I stopped the system, restarted and made at first step a complete HDD- Backup with Acronis.

Then I made my update and deployed the libraries again (without errors).

Starting of the software failed with a message "Cannot read shared variable XY" or "Cannot write shared variable XY". After 10 hours of playing around, restarting refreshing backups and ....... I decided to use the old version.

I made a complete disc restore including formatting. The system comes up well.

The "old" program is not running anymore as well with the same errors. Playing around with rebooting, deploying but without any code changes let the program start two times, but failed for approximated (no kidding) 50 times. Deploying simplest libraries with just one value bounded to a modbus node destroy all (different) deployed processes and variables, no connection is possible anymore.

I can find some message in the system event list, content is attached. But this messages appeared in january as well when the software was running.

To get a starting point my first idea is to check modbus connection with just one value. I have no connection and cannot see the node over the network elements view.

In the current buglist I found nothing what matches my problem...

Can somebody help me on this issue, please.....

Best regards

Tim

[nickf]

Hi Tim,

Here are some additional debugging steps to consider:

• What happens if you disable one network card then reboot?  Will the variables start correctly?
• Have you configured the logos.ini file to point to a specific network adapter?  (KB 4CK7NM0L)
• Do you have any virus scanner software that could have applied updates on the reboot cycle?  Some virus scanners include IP monitoring filters that could block variable or TCP related traffic.
  
• Have you tried using the Variable Manager utility to remove all active processes and then redeploy from scratch?
• You mentioned that deploying a Modbus IO server will immediately bring down all other variables in the system.  --Have you tried deploying the DSC Modbus examples?
  
• Can you successfully stop and start the National Instruments Variable Engine service from the Windows service manager? (Or, do you have to use the task manager to kill the tagger.exe process after attempting to stop the service?)
• Can you deploy a simple library that contains only a Modbus IO server without any variables bound to it?
• Do you encounter the same behavior when deploying the OPC Client I/O server?

-Nick