[erlang-questions] Possible hostname handling bug in node handshake procedure?

Bengt Kleberg <>
Tue Nov 24 10:26:46 CET 2009


What are your ideas about both parts of the node name? Should they be
case insensitive or just the host name part?

Consider the node 

It might be confusing to have
net_adm:ping() => pong
but then get
net_adm:ping() => pang

So we probably should have case insensitivity here. But then we have to
explain why aA =:= aa is false in all the rest of the code.

Perhaps this is a problem only for me.

On Tue, 2009-11-24 at 09:47 +0100, Maas-Maarten Zeeman wrote:
> Today I stumbled upon some strange behavior when using net_adm:ping.  
> I  was trying to connect two machines, buka  and Edo on the same lan,  
> but it just would get them to talk to each other. Net_adm:ping worked  
> in one way only. Normal ping worked both ways, double checked if there  
> where firewall rules. I even looked at the network packets, which I  
> could see arriving at both ends. Then it slowly dawned on me. One of  
> the hosts has a hostname with a capital in it. so I tried to the exact  
> name. It worked...
> Here is what happens.
> ()1> net_adm:ping().
> **long wait**
> pang
> ()2> net_adm:ping().
> pong
> In both situations the network packets arrive at  To me it looks
> like there is a case sensitivity problem with the hostname handling in  
> the  handshake procedure.
> ()51> net_adm:ping().
> pong
> ()52> net_adm:ping().
> pang
> Shouldn't both calls return pong as hostnames should normally be  
> treated as case insensitive strings?
> Kind regards,
> Maas-Maarten Zeeman
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