Possible hostname handling bug in node handshake procedure?

Maas-Maarten Zeeman <>
Tue Nov 24 09:47:05 CET 2009

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**
()2> net_adm:ping().

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().
()52> net_adm:ping().

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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