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DNS / Netbios Slowing Down LXI SCPI response

Question asked by dking on Jan 29, 2015
Latest reply on Feb 9, 2015 by MarkL
I've have a script that grabs capture data from the DSO-X 3034A in order to preform some calculations and generate a few of plots.   The script worked just fine on another Agilent scope on a different networking setup.  However, now the script times-out waiting for a response from the scope.   I had to set receive timeout to 20 seconds to get any response at all.

At first I thought it was a networking issue, so connected the second network card on my PC and set a static address on the scope.   I get ping times of < 1ms and no packet loss.   However, script it still rediculously slow.

I changed the script so the only thing it did was send an "*idn?" request and it still tooks about 20seconds to get a response.

I ran wireshark to see what traffic was being sent back and forth.  I found that the scope was sending DNS reverse hostname lookups for my IP address instead of sending a response.  It would send 3 DNS lookups (with a long delay between each) before finally giving up and returning a response to the  *idn? request.  

I'm put my IP in the building DNS server and now things work just fine.    However I shouldn't need to do this to use a TCP/IP connection to the scope.   There is no reason the scope **NEEDS* my hostname to send TCP/IP data.

Is there any way I can disable DNS and NetBIOS on the scope?   The scope shows Dynamic DNS and NetBIOS and as being enabled in the utility->networking, but doesn't provide any option for disabling them.  I've did a quick search of the manual and didn't find anything.  

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