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Subject: Re: [OMPI users] openmpi 1.6.3 fails to identify local host if its IP is 127.0.1.1
From: Riccardo Murri (riccardo.murri_at_[hidden])
Date: 2013-06-26 04:26:40


Hello,

On 26 June 2013 03:11, Ralph Castain <rhc_at_[hidden]> wrote:
> I've been reviewing the code, and I think I'm getting a handle on
> the issue.
>
> Just to be clear - your hostname resolves to the 127 address? And you are on
> a Linux (not one of the BSD flavors out there)?

Yes (but resolves to 127.0.1.1 -- not the usual 127.0.0.1), and yes
(Rocks 5.3 ~= CentOS 5.3).

> If the answer to both is "yes", then the problem is that we ignore loopback
> devices if anything else is present. When we check to see if the hostname we
> were given is the local node, we resolve the name to the address and then
> check our list of interfaces. The loopback device is ignored and therefore
> not on the list. So if you resolve to the 127 address, we will decide this
> is a different node than the one we are on.
>
> I can modify that logic, but want to ensure this accurately captures the
> problem. I'll also have to discuss the change with the other developers to
> ensure we don't shoot ourselves in the foot if we make it.

Ok, thanks -- I'll keep an eye on your replies.

Thanks,
Riccardo