using data socket with ni opc server exceeding the max connection number

[royceking]

we are now using data socket with ni opc server to communicate with S7 PLCs.

now we have totally 3200 connections built by data socket open vi, stored in DVR, but occasionally, the write operation is ok while the value in plc is not updated!

notice that in data socket server, the max connection number is 1000 and now we have 3200 connections.

at this time , how does the data socket server process  and whether this is the reason!

many thanks!

[wiebe@CARYA]

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@royceking wrote:

now we have totally 3200 connections built by data socket open vi, stored in DVR,

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Why?

Or rather, why not open one connection, and read\write 3200 times over that connection?

[royceking]

because we have 3200 items on the opc server

[wiebe@CARYA]

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@royceking wrote:

because we have 3200 items on the opc server

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But you don't need 3200 connections. One connection can read\write 3200 items.

[royceking]

curious about how? how one connection can read/write 3200 items.

maybe there is some misunderstand.

here, 3200 connections, i mean open datasocket with specific url 3200 times.

and you mean 3200 items use one tcp conneciton as this white paper says? 

http://www.ni.com/zh-cn/innovations/white-papers/06/datasocket-transfer-protocol--dstp--overview.htm...

The DataSocket server uses the same TCP connection for all DataSocket items that exist within the same process space.

[wiebe@CARYA]

Ah. Sorry about that. The old DS does seem to require the URL at open time.

This DS stuff is old. In fact, IIRC, it's been announced obsolete for years now.

IIRC, you can access DS with either raw TCPIP and\or Shared Variables. You can open a SV connection and use it to read multiple URLs. I'm not sure if that resolves the limit though.