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<p class=MsoNormal>I have been working through the Getting Started tutorial (<a
href="http://www.erlang.org/doc/getting_started/part_frame.html">http://www.erlang.org/doc/getting_started/part_frame.html</a>)<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>In section 3.4 there is an example program called tut17
which shows how to get two nodes on different computers to communicate.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I compiled this program on two Ubuntu virtual machines and
ran it per the instructions. I started ‘pong’ on one machine,
then ‘ping’ on the other. ‘pong’ emits ‘ok’
and returns the command prompt immediately (I am guessing it spawned a process
which remains running). ‘ping’ emits ‘<0.43.0>’
and also returns to the command prompt immediately.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>So there are no errors, but I don’t see the expected
output, which is a series of ‘ping received pong’ and ‘pong
received ping’ messages on either side. It is as if the output is
not reaching the terminals, or the programs are unable to communicate.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I wondered whether I had correctly set up the cookie file,
or whether there was some security or firewalling that was getting in the
way. The two machines are in the same subnet and each can ping the
other. But when I ran the following example from the tutorial (tut18,
where the program spawns a process on the other machine) it was successful –
so it seems that communications and security things are OK.<o:p></o:p></p>
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