[McIDAS #SRD-104827]: ADDE port trouble again

Hi Suvarchal and Brian,

We have put together a proof of concept hack for the problem you have been
experiencing when trying to load satellite imagery served by ADDE when
on networks that are blocking outbound traffic to port 112 (the port
that ADDE servers listen on), and we would be most appreciative if you
could try it out for us!

NB: The hack we have implemented is only available in test mode
on adde.ucar.edu so far.  It was implemented by installation of a program
named 'balance'.  'balance' listens for connections on an administrator
specified port and redirects those connections to port 112 on an
administrator specified server.

Test details:

- install the 'ADDE via port 80' plugin in the IDV instance that
  you can run while connected to a network where outbound traffic
  to port 112 is being blocked

  The WiFi/wired networks in computer labs located on the main UMiami
  campus should be good candidates for this test, but you should definitely
  try the test on the same network(s) where you have experienced difficulty
  in loading satellite imagery from adde.ucar.edu in the past.

- try loading your NAmonsoonbest.xidv from the IDV configured with the
  'ADDE via port 80'

  I have run the tests here, and am reasonably confident that there will be
  no unintended side effects for the duration of the test.

Comments:

- the IDV should load all of the datasets referenced in your NAmonsoonbest.xidv 
bundle
  with no problems on any network when configured with the 'ADDE via port 80' 
plugin

- NB: you will _NOT_ be able to access any other ADDE server from any network
  while the 'ADDE via port 80' plugin is installed!

- the results of your test definitely say that the cause of the problems
  you have been experiencing is a lockdown on the network where the problems
  have been experienced

  If, as we expect, your problem really is being caused by a network lockdown,
  we will work on IDV code modifications that will do one or both of the
  following to get around such lockdowns:

  - test access to ADDE servers via port 112 as a default and switch to
    port 80 if access is being denied

  - add the ability to specify the port to talk to an ADDE server on via
    the common ':<port>' syntax at the end of the server name

    Example:

    adde.ucar.edu    -> ADDE access via port 112 to adde.ucar.edu
    adde.ucar.edu:80 -> ADDE access via port 80 to adde.ucar.edu

    Adding this capability would allow the ADDE administrators
    to service requests on any port that they choose ** as long
    as they also implement the 'balance' bent piping of requests
    on the same machine **.

  - we will also implement the 'balance' bent piping on all of the ADDE
    servers in our control (this includes weather.rsmas.miami.edu) AND
    contact the administrators of ADDE servers not under our control and
    lobby them to implement the 'balance' bent pipe "solution"

Important:

As soon as you are done testing your NAmonsoonbest.xidv bundle (or any
other bundle that tries to load satellite imagery from adde.ucar.edu),
you should remove the 'ADDE via port 80' plugin from the IDV.  This is
so you will not forget that the plugin will be mucking with all calls
made to ADDE servers.

Please let us know if you have any questions about the test outlined
above.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: SRD-104827
Department: Support McIDAS
Priority: Normal
Status: Closed