Datasocket Startup Error

[Ian R]

We have a system consisting of four data acquisition PCs running Windows 2000 SP4 (Pentium III,

256MB Ram) which write data via datasockets to a server PC (dual Pentium III, 1.5GB Ram, Raid 5,

also runs Oracle 9i Standard) running Windows 2000 Server SP4.

The system was developed using LabVIEW 6.1 and the Database Connectivity Toolkit 1.0.1 and the

datasocket server ersion is 4.0(377)

On startup a LabVIEW program on the server PC starts the datasocket server. On three of the data

acquisition PCs the LabVIEW program that acquires the data is started, and once all three are on,

they simultaneous begin to broadcast data to the datasocket server on the server PC once a second.

The LabVIEW program on the fourth PC is then
started and also beings to broadcast data to the

datasocket server once a second.

The data, the data acquisition PC are broadcasting is bundled together using the Set Variant

Attribute function and has the following structured

Timestamp Double
Date Acquired once Per Second 1D array of singles (240 items)
50 Hz Timestamp Double
50Hz Data 2D array of singles (empty on startup)

The datasocket from each PC has a unique name (e.g. PC1 one is data1, PC2 is data2, etc.)

The problem is that it usually takes about three goes to start the system, the first two goes

resulting in datasocket errors (63) and if you move the mouse across the datasocket server icon in

the system tray it disappears.

Usually the system starts successfully on the third attempt, and the datasockets stay running for

as long as the system is running (i.e. days or weeks).

Does anyone have any ideas why these problems occur on startup.

Thanks

Ian Rile
y
Business Systems Manager
AudioSoft Ltd.

[Steven Bird]

Hello Ian, I am unsure why this is occuring and from the information I have read it seems this is a network permissions issue?

Labview (error codes):
63 ncConnRefusedErr The network connection was refused by the server.

If this is the case what you can do is monitor the error cluster, if this error occurrs you can retry the connection until it is successfully. This can easily be done using clear error vi. You can also stop the vi from reporting this dialog box on the screen (see simple / general error handler vi's context help).

I have also found a knowledge base entry that may help you that is directly related to your issue:

http://digital.ni.com/public.nsf/websearch/CE62D869535D602F86256D330060F5F1?OpenDocument

Hope this helps?

Steven Bird

[Andrey_Dmitriev]

Ian,

I've got nearby the same problem (but in LabVIEW 7.0 under Win2000SP4).
Symthoms are followings:
DataSocket server crashed after start. I have tried differtent ways for startup - launch by DataSocket Server Control.vi or direct call of cwdss.exe.
It started, then connection established, and then cwdss.exe closed (with exception and record in Dr.Watson log)
I have absolutely same behavior as you described here " if you move the mouse across the datasocket server icon in the system tray it disappears." It means, that cwdss.exe unexpectable closed.

Interesting, that this problem not present on my development computer, but on all target machines (six computers at least) it happened. It happened not always. Sometimes (very rarely) DS Server st
arted properly.

The "best" solution which i have found is starting DataSocket as service. I wrote simple vi, with launch DS Server, then i have compiled this vi into exe, and put this exe as Windows Service. Now at least it works properly without any startup problems. Disadvantages of this - you will not see any more DS Server icon in system tray (but you can check that DS Server is started by presence cwdss.exe in TaskList.

Some documentation about this can be founded here:
Creating a Windows NT Service Using LabVIEW
http://zone.ni.com/devzone/conceptd.nsf/webmain/A9B2FA96B851394586256B26006ECB98?opendocument

Some VIs and utilities in attachment

Not really sure, that you have _exact_ the same trouble, but may be my solution will help you too.

Andrey.

[Ian R]

Steven

Thanks for the advice, I have looked at the knowledge base entry, however our system does not have a firewall, as it just uses the internal Windows 2000 Server router and it is not connected to any external network.

Ian Riley

[Ian R]

Andrey

Thanks for the advice. We have actually found that if we start the data acquisition PCs in a different order, we get a lot less occurances of the datasocket server crashing.

I probably try starting DataSocket as a service next time we perform some modifications to the system.

Ian Riley