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20030923: Two LDM's not talking to each other

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  • Subject: 20030923: Two LDM's not talking to each other
  • Date: Wed, 24 Sep 2003 09:20:42 -0600
Alan,

>Date: Wed, 24 Sep 2003 10:46:43 -0400
>From: "Alan Hall" <address@hidden>
>Organization: NOAA
>To: address@hidden
>Subject: [Fwd: LDM problems on doppler]

The above message contained the following:

> Do you have a general flow of the LDM process that I can give to my systems
> folks?  

Not yet.  Use the following.

    1.  A downstream LDM client connects to an upstream LDM server 
        using ONC RPC to program number 300029, protocol version 6
        over a TCP-based socket connection to port 388.
        
    2.  The downstream LDM sends a synchronous ONC RPC request for data
        and awaits a reply.

    3.  The upstream LDM sends a positive reply to the request.

    4.  The downstream LDM creates an ONC RPC server-side handle using the
        socket of the previous connection and awaits data using the
        select() system-call.

    5.  The upstream LDM creates an ONC client-side handle using the socket
        of the previous connection.

    6.  The upstream LDM sends data over the client-side handle using
        asynchronous ONC RPC messages.

ONC RPC is a mature (i.e., old) technology.  It has been superceeded by
TI (transport independent) RPC.  Could it be that the ONC RPC library was
replaced with a TI RPC one?  This happened with HP-UX 11.  The solution
was to tell the LDM package to use the "librpcsoc.a" compatibility
library.  You might search for "rpcsoc" on your system.

Regards,
Steve Emmerson