: net_adm:ping not working -- still not answered

erlang <>
Fri Sep 1 21:14:16 CEST 2006


pings work ok. My system runs everything I have ever thrown at
it. cygwin, mysql, sql server, perl and php apps, anything that
opens local ports for sommunication -- all perfect until now with Erlang.

I tried taking out the dash in the computer name,
it makes no difference.


> Does the following work?
> 
>  C:\> ping localhost
>  C:\> ping my-server
> 
> 
>  If no, get them working before delving into the erlang ping.
>  If yes, hmmm.  Not certain though maybe my-server hostname
>  should be changed to myserver (possibly the dash is problematic).
> 
> 
> ~M
> 
> On Fri, Sep 01, 2006 at 10:54:35AM -0700, erlang wrote:
> > Yes, you have shown the tests I am using, very simple cases. 
> > But I get pangs, and timeouts.
> > 
> > I agree it is probably due to a  misconfigured network. What I have
> > is one Windows Server 2003 sp1 machine that is setup for a 
> > peer-to-peer workgroup, with no local dns server, domain controller, 
> > etc. I agree that my problem is most likely a network configuration 
> > that is not Erlang friendly. I couldn't find a prerequisites list for Erlang 
> > so I'm not sure what it needs. I have used many applications that have no
> > problem opening ports on localhost.
> > 
> > 
> > > 
> > > Well, it should work.
> > > 
> > > Try the following diagnosis:
> > > 
> > > $ erl -sname a
> > > $ erl -sname b
> > > 
> > > ()> erl_epmd:names().
> > > {ok,[{"a",43500},{"b",43505}]}
> > > ()> inet:gethostbyname("my-server").
> > > {ok,{hostent,"my-server",[],inet,4,[{192,168,0,100}]}}
> > > ()> net_adm:ping('').
> > > pong
> > > ()> nodes().
> > > ['']
> > > 
> > > 
> > > And if that does not work as above try:
> > > 
> > > $ erl -sname 
> > > $ erl -sname 
> > > 
> > > ()> inet:gethostbyname("localhost").
> > > {ok,{hostent,"localhost",[],inet,4,[{127,0,0,1}]}}
> > > ()> erl_epmd:names().
> > > {ok,[{"b",43527},{"a",43530}]}
adm:ping('').
> > > pong
> > > ()> nodes().
> > > ['']
> > > 
> > > 
> > > I am suspecting your machine may have misconfigured network.
> > > 
> > > To make sure the cookie is the same, add the argument
> > > -setcookie my-cookie4711
> > > to the command line of both nodes, but if you have the wrong cookie,
> > > the target node should print: 
> > > =ERROR REPORT==== 1-Sep-2006::09:40:06 ===
> > > ** Connection attempt from disallowed node  ** 
> > > when net_adm:ping() fails.
> > > 
> > > 
> > > 
> > > On Thu, Aug 31, 2006 at 09:29:48AM -0700, erlang wrote:
> > > > > 
> > > > > Sorry, this is indeed a typo in my email. Should be:
> > > > > ()1> net_adm:ping('').
> > > > > 
> > > > > > 
> > > > > > Hi, is the colon ":" just a typo in your email? It should be
> > > > > > "@
> >  you can see from the node name in the Erlang shell prompt.
> > > > > > 
> > > > > > Best Regards
> > > > > > Lennart
> > > > > > 
> > > > > > > ()1> net_adm:ping('a:my-server').
> > > > > > 
> > > > > > > I can't get the ping-pong distributed example to work, so I tried simply
> > > > > > > pinging another node. This doesn't work either.
> > > > > > > 
> > > > > > > os: windows server 2003, machine name is my-server.
> > > > > > > EShell v5.5.1
> > > > > > > 
> > > > > > > command lines: erl -sname a
> > > > > > >                             erl -sname b
> > > > > > > 
> > > > > > > ()1> net_adm:ping('a:my-server').
> > > > > > > 
> > > > > > > always returns pang. The cookie file is being read, and the cookie is
> > > > > > > the same in both nodes. What to try next?
> > > > > > > 
> > > > > > > 
> > > > > > > 
> > > > > > > 
> > > > > > > 
> > > > > > > 
> > > > 
> > > > 
> > > 
> > > -- 
> > > 
> > > / Raimo Niskanen, Erlang/OTP, Ericsson AB 
> > 
> > 
> > 
> 
> -- 
> Michael McDaniel
> Portland, Oregon, USA
> http://autosys.us
> +1 503 283 5284 






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