Network published variables issue between 2009 - 2011 labview

[Josh_656]

Hello,

As part of a final engineering project, I have been assigned to fix an issue with one of the university’s systems. Basically the original setup used a master server which ran, and every other computer in the lab communicated with the system through published shared variables. This worked fine until the computers in the lab were upgraded to win 7 with lab view 2011.

I’ve successfully created a VI test program which uses published shared variables to communicate between two win7/2011 lab view computers (so it is not a firewall issue or access issue)

I believe that the issue is that the variables are not being deployed properly on the Xp/2009 system, or that the win7/2011 labview has compatibility issues with accessing the winXp/2009 labview shared variables.

An interesting note is that if I open up Distributed System Manager (on a win7 computer), I can find the XP machine and openen it up, but when I try to expand the library of variables it comes up blank and crashes the XP/2009 VI, giving an error on the XP machine saying that the variables cannot be found.

The XP/2009 labview computer is being upgraded but is going to take a while, anyone know of any solutions?

[Josh_656]

* Also some computers were converted back to XP/2009 so that lab could still run. These can communicate properly, so it has to be some sort of compatibility issues between xp/2009 lab view and win7/2011 labview when using network published shared variables.

[Ever_Song]

Hi Josh_656,

First off, here is a document that deals with troubleshooting Network-Published Shared Variables that might prove useful.

Next, I have some basic questions:

- Are the computers on the same IP subnet (most likely since you can see the other computer but worth checking anyway)?

- What specific error code/text did you receive when trying to access the shared variable library (a screenshot would be helpful)?

- How exactly are the computers communicating (I presume Ethernet)?

Some things to try:

- Try and see if opening up ports listed here helps.

- Make sure that NI Variable Manager and NI Distributed System Manager services are running.

[Josh_656]

Hey, thanks for the reply

Yes I did run through the trouble shooting, everything was set up properly, aliasing the correct variables etc,

Yes it is over Ethernet,

It’s not a firewall issue, as win7/2011 labview computers can share variables (TEST IV CREATED), and the xp/2009 computers (the original system) can communicate and run the lab properly. (I will test the ports anyways)

It’s only when the cross platform sharing is attempted, that the problem exists. I know it’s a bit of a hassle and the easiest way is to upgrade the XP/2009 machine, but that’s going to take a while.  

I’m going to make a test VI on the 2009 labview later to isolate the particular server/VI as the issue, but I highly doubt that the VI will be causing the issue.

Yes the computers are all on the same IP subnet.(Yes this has been thoroughly checked)

The error code is, -1950679020, I found a thread on a similar issue, suggesting that the SVE isn't running, but it obviously is, other wise my TEST vi wouldn't work nor would the Xp to XP communication work.

The message received with the error is, "this error or warning occurred while reading the following shared variable, \\mycomputer\client_library\ES1_DI_Array, \\192.168.97.243\Client_library\ES1_Di_Array

But isint much help, the error suggests that the variables are not deployed correctly/at all ( yes they are on the XP machines, but the Win7 can't find/view them as mentioned in the first post).

Any further suggestions would be appreciated, I will try a simple VI to share variables from the XP/2009 labview machine.

[Josh_656]

Interesting note..... A simple VI test program across the two platform (XP/2009,Win7/2011) worked!.

So something must be wrong with the VI.

Another point, I attempted to open the server VI on 2011 labview, and it stated it was corrupt, yet it opens on the 2009.

Unless there is some reason for why this is happening, the only solution I can think of is removing all shared variables, (there's over 200 variables),

and re-creating them. 

[BenDAE]

Josh,

I looked up that error for you and found that it may be due to the following: Unable to access the shared variable. This error can occur if you attempt to read from a write-only variable or write to a read-only variable, or if you do not have permission to access the variable.

Do you happen to know if this symptom matches your particular VI's?

[Josh_656]

This has been checked thoroughly. It is not a permissions/firewall issue and all shared variables have the correct read/write status.

[Josh_656]

New update... labview 2011/win 7 now running server... Variables can be seen on other computers in the lab! But when viewing them in distributed systems manager it says connecting then the following error appears

IAK_SHARED: (hex0x8ABC5003) the connection to the server has been lost

Anyone know of this error?

[Josh_656]

New update again, yes I can now see the shared variables from the NEW win7/2011 labview computer. But they try to connect and I receive the error mentioned in the post above.... However...

The old XP/2009 machines/clients in the lab can connect and view the variables?!?!.. So the problem so far in summary because this is getting a bit hetic...

1. NEW Test VI that was created in 2011 labview confirms that shared variable transfer over the network is possible between a client computer and The Server computer in the lab.

2. The server is now 2011 labview/win7 computer

3. The server VI is successfully running on the new computer.

4. The win7/2011 labview clients cannot connect due to the previous mentioned error

5. The old XP/labview 2009 machines can connect and no issues experienced.

6. This means that the master VI/server has to be the problem!

... Conclusions?.. The shared variables originally created on the master VI/2009labview/XP are not accessible by the newer version of labview/win7

[BenDAE]

It appears that your shared variables are hosted on the Win 7 LabVIEW 2011 computer, but only being read by the client computers running Windows XP with LV 2009. It sounds like there may be a firewall issue. Please check if you can see the variables using the Distributed Systems Manager on the Win 7 client computers.

Also, here is an article describing which ports you want to make sure aren't blocked in case the firewall is the issue.

http://digital.ni.com/public.nsf/allkb/8AE45BBFA1D7025E862570F200642FD8?OpenDocument