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[LDM #UWP-301248]: LDM Connection problem

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  • Subject: [LDM #UWP-301248]: LDM Connection problem
  • Date: Fri, 17 Aug 2012 14:12:04 -0600
Hi Jerry,

re:
> Michael is trying to access the SPARE feed on one of our LDM servers.   He is 
> getting the error:
> 
> "couldn't connect to LDM 6 on fred.ssec.wisc.edu using port 388; : RPC:  
> Remote system error - Connection refused"
> 
> He can ldmping our server.   Other external users can access the ldm SPARE 
> feed.  (see some details below)

Actually, the ldmping output Michael sent along:

> [ldm@opc-lw-goesrpg: ~/ldm/etc]$ ldmping -i 5 -h fred.ssec.wisc.edu
> Aug 17 18:28:45 INFO: State Elapsed Port Remote_Host rpc_stat
> Aug 17 18:28:45 INFO: Resolving fred.ssec.wisc.edu to 128.104.109.245 took 
> 0.032546 seconds
> Aug 17 18:29:02 INFO: Resolving fred.ssec.wisc.edu to 128.104.109.245 took 
> 0.001244 seconds
> Aug 17 18:29:19 INFO: Resolving fred.ssec.wisc.edu to 128.104.109.245 took 
> 0.001223 seconds
> Aug 17 18:29:36 INFO: Resolving fred.ssec.wisc.edu to 128.104.109.245 took 
> 0.001181 seconds
> Aug 17 18:29:53 INFO: Resolving fred.ssec.wisc.edu to 128.104.109.245 took 
> 0.001149 seconds
> Do you have any ideas why he can not connect?

shows that his LDM can _not_ connect to the LDM on fred.ssec.wisc.edu.  The 
output for
an LDM that can connect will look like:

$ ldmping oliver.unidata.ucar.edu
Aug 17 20:07:48 INFO:      State    Elapsed Port   Remote_Host           
rpc_stat
Aug 17 20:07:48 INFO: Resolving oliver.unidata.ucar.edu to 128.117.156.17 took 
0.009147 seconds
Aug 17 20:07:48 INFO: RESPONDING   0.075321  388   oliver.unidata.ucar.edu  

The RESPONDING line indicates that the upstream LDM has responded to the 
ldmping.

What is the result of:

notifyme -vl- -h fred.ssec.wisc.edu

If this invocation "hangs", it is likely that Michael's LDM is not able to 
contact
the LDM on fred.ssec.wisc.edu.  We see two different reasons for this:

- the firewall on fred.ssec.wisc.edu is blocking the port 388 connection 
attempt from
  Michael's machine

- a firewall at or near Michael's machine is blocking outbound port 388 
connection
  attempts

Cheers,

Tom
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Ticket Details
===================
Ticket ID: UWP-301248
Department: Support LDM
Priority: Normal
Status: Closed