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Janet, >Date: Fri, 17 Jun 2005 13:20:17 -0600 >From: Janet Scannell <address@hidden> >Organization: UCAR/EOL/ATD >To: Steve Emmerson <address@hidden> >Subject: Re: Getting LDM on plane to receive via UCAR RAS and PPP The above message contained the following: > Actually, cirque.p3.public.net is a private ip address, so it is not in > dns anywhere. cirque uses nat and ip masquerading to get data to and > from the ground during flight. Now, I have a ppp link on the plane > that is working and I can ping linus.atd.ucar.edu which is my upstream > ldm from cirque. When I try using ldmping to linus.atd.ucar.edu, it > either gives a portmapper error or says that gethostbyname timed out. This means that the ldmping(1) on Cirque never reached Linus. Because a ping(1) of Linus from Cirque worked, we suspect that a firewall between Cirque and Linus isn't allowing traffic on port 388 to pass through. You can test this hypothesis by executing the command rpcinfo -t linus.atd.ucar.edu 300029 6 on Cirque (you might have to adjust the arguments: the "-t" means "TCP"). I suspect that it won't be able to connect. We've encountered firewall problems like this numerous times. > Therefore the ldm feed is not working to cirque and I was wondering if > you have any ideas that would help me out. I have made the standard > entries in the /etc/services and /etc/rpc files and I did have the ldm > working when cirque was attached to the local network with a different > ip address. > > Thank you, > Janet Regards, Steve Emmerson