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20060217: Sending data through LDM to ground from aircraft with changing ip address (cont.)

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  • Subject: 20060217: Sending data through LDM to ground from aircraft with changing ip address (cont.)
  • Date: Wed, 15 Feb 2006 09:48:02 -0700
>From:  Steve Emmerson <address@hidden>
>Organization:  UCAR/Unidata
>Keywords:  200602150016.k1F0GJO7018959

Hi Steve,

re:
>>Date: Tue, 14 Feb 2006 15:55:32 -0700
>>From: Janet Scannell <address@hidden>
>>Organization: UCAR/NCAR/EOL/ATD
>>To: Steve Emmerson <address@hidden>
>>Subject: Re: 20060113: Sending data through LDM to ground from aircraft with 
>>changing ip address (con
> t.)
>
>The above message contained the following:
>
>> I tried the beta version of the ldm code that you made to fix this 
>> problem.  What I found is that the ldm no longer reports error messages 
>> in the log when the ip address changes and it can no longer reach the 
>> old host, but the data from the new ip address on the plane to the 
>> ground never gets to the downstream ldm.  It looks like part of the ldm 
>> code is determining that the host name still exists, but there is still 
>> some part that needs updating for the data to actually reach the ldm on 
>> the ground.
>
>I'm sorry to hear this.
>
>At this point, the downstream LDM on the ground is doing all that it can
>to obtain the correct IP address for the given hostname on the plane.
>The lack of error messages indicates that the downstream LDM on the
>ground is timing-out in its attempts to contact the upstream LDM on the
>plane.  You should be able to see this by starting the LDM on the ground
>in verbose mode via the "-v" option to ldmadmin(1) -- alternatively, you
>can send a running downstream LDM process a USR2 signal to put it into
>verbose mode.
>
>I wish I could tell you something encouraging, but the network (not the
>LDM) just isn't playing nice.
>
>Tom, you got any ideas?

I have no idea what is going on.  It may be useful for us to visit Jeffco
and take a look.  I can go, but the visit would have to wait until Friday
at the earliest since I am in Fraser at the moment for two days of skiing :-)

Cheers,

Tom
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* Tom Yoksas                                             UCAR Unidata Program *
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