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Re: 20060113: Sending data through LDM to ground from aircraft with changing ip address (cont.)

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  • Subject: Re: 20060113: Sending data through LDM to ground from aircraft with changing ip address (cont.)
  • Date: Fri, 20 Jan 2006 16:07:54 -0700
Janet,

I've discovered a system-call that might clear any cacheing of IP
addresses by the operating system and added a call to it to the
downstream LDM code.  The resulting distribution is experimental -- but
I suggest you try it to solve your problem.

If it doesn't solve your problem, then there's nothing more that the LDM
can do.

The URL for the release is

    ftp://ftp.unidata.ucar.edu/ldm/ldm-6.4.5.0.tar.Z

Please let us know what you discover.

Regards,
Steve Emmerson
LDM Developer

------- Original Message

Date:    Thu, 19 Jan 2006 23:50:21 -0700
From:    Unidata Support <address@hidden>To:      semmerson@unidata.u
          car.edu
Subject: 20060113: Sending data through LDM to ground from aircraft with changi
          ng ip address (cont.)


------- Forwarded Message

>To: Unidata Support <address@hidden>
>From: Janet Scannell <address@hidden>
>Subject: Re: 20060106: Sending data through LDM to ground from aircraft with c
hanging ip address
>Organization: UCAR/Unidata
>Keywords: 200601132309.k0DN9O7s021011


We have an ISP for our satellite connection that gives us the same name 
each time we connect, but not the same ip address. (i.e. 
600644362.tssmob.net is the name and 12.42.105.* for the ip address, the 
last number varies for each connection).  After the satellite connection 
is made, it takes about 5 minutes for the name, 600644362.tssmob.net, to 
resolve to the correct address from the plane.  Once the name is 
resolved properly, then we start up the processing that sends the ldm 
data to the ground.   The name is what is specified in the conf file on 
the ground (request EXP "nimbus_sql.*\.gz" 600644362.tssmob.net).  The 
ldm on the ground has to be restarted each time a new connection is made 
from the plane before the data will get to the ground ldm.   This seems 
to be a problem with the ldm connection and not a problem with the dns 
name resolution.  The problem that I see on the ground is that the data 
is not being received by the ground ldm.  When I restart the ldm, the 
data immediately starts flowing to the ground ldm.   I'm trying to find 
out the range of available IP addresses that we could be assigned.  The 
ip address can change any time we reinitiate the connection with the ISP.

Janet


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------- End of Forwarded Message

------- End of Original Message