Open MPI logo

Open MPI Development Mailing List Archives

  |   Home   |   Support   |   FAQ   |  

This web mail archive is frozen.

This page is part of a frozen web archive of this mailing list.

You can still navigate around this archive, but know that no new mails have been added to it since July of 2016.

Click here to be taken to the new web archives of this list; it includes all the mails that are in this frozen archive plus all new mails that have been sent to the list since it was migrated to the new archives.

Subject: Re: [OMPI devel] Additional excluded tcp inteface
From: Rolf Vandevaart (Rolf.Vandevaart_at_[hidden])
Date: 2008-11-07 16:27:15


On 11/07/08 11:23, Adrian Knoth wrote:
> On Fri, Nov 07, 2008 at 09:49:43AM -0500, Rolf Vandevaart wrote:
>
>> I do not think anyone will have a problem with this, but just thought I
>> would mention that I am planning on adding an additional interface to
>> the excluded list for the tcp btl. I want to add "sppp" to the list.
>> This is an internal interface to one of our servers and needs to be
>> treated like the "lo" interface.
>
> Is it possible to detect this interface and exclude it right from the
> beginning in opal/util/if.c? Special flags that apply to this interface,
> so we have a classification?
>
>
> Just my $0.02
>
I considered this. I believe the sppp0 is a "point-to-point" interface,
so I see that the IPv6 code has actually done something like this.

             if(0 != (cur_ifaddrs->ifa_flags & IFF_LOOPBACK)
                     || 0!= (cur_ifaddrs->ifa_flags & IFF_POINTOPOINT)) {
#if 0
                 printf("skipping loopback interface %s.\n",
cur_ifaddrs->ifa_name);
#endif
                 continue;
             }

However, the IPv4 code does not do this. In fact, the loopback check is
#ifdef'ed out.
#if 0
         if ((ifr->ifr_flags & IFF_LOOPBACK) != 0)
             continue;
#endif

So, in order for things to work properly in both case, I wanted to mimic
what was done for lo interfaces. I am leery about duplicating the IPv6
code in the IPv4 code as I looked at earlier discussions on the mailing
list saying that was a bad idea.

http://www.open-mpi.org/community/lists/devel/2008/02/3290.php

So, just adding it to the list of the excluded interfaces seemed the
safest fix to me.

Rolf

-- 
=========================
rolf.vandevaart_at_[hidden]
781-442-3043
=========================