[omniORB] Can't connect to server when launched from Linux?!?

[Sai-Lai Lo]

This is another frequently encountered problem with recent redhat
installations. I don't know if other installations do the same. IMO, it is
not how one should configure a networked machine.

Redhat always put something like this in your /etc/hosts:

127.0.0.1    foo localhost.localdomain localhost

This is ok if yours is a home machine with just a dialup interface.
But on a networked machine, if you have that entry and one do a name to
address lookup for "foo", what you get is 127.0.0.1. In other words, one
cannot find out what the real IP address of your host is.

By default, omniORB always try to use the IP address, instead of the
hostname in the IORs it gives out. So it uses host to address lookup.
And it gets 127.0.0.1. Being a local loopback network interface, the
address obviously cannot work on other machines.

The solution is either:

1. Remove "foo" from the /etc/hosts, (PREFERRED)
2. Start your server with this ORB option:
      $./eg2_impl -ORBpoa_iiop_name_port "foo"

Regards,

Sai-Lai



>>>>> John D Heintz writes:

> Hello,every one:
> Our system setup is pretty simple and common.

> We are launching an "omniNames -logdir <somewhere>" and our Python
> server script with
> "python launch.py -ORBInitRef NameService=corbaname::localhost".

> This script creates a servant and object reference, gets a ref to the
> NameService, and binds (actually rebinds) a string name to the object
> reference.

> A client test script uses "corbaname::hostname#ServerName" to connect.

> This works perfectly for localhost client and server, it works for
> windows based server and any client, it does not work for linux based
> server and any non-localhost clients!

> We have also checked our hosts.allow and hosts.deny files, ultimately
> trying "ALL : ALL" in hosts.allow just to be sure.

> Here is the trace from the failing client connection, followed by the
> start where the successful client connections pick up and continue.



-- 
Sai-Lai Lo                                   S.Lo@uk.research.att.com
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