Re: /proc/net/igmp group address encoding

Pekka Savola <pekkas@xxxxxxxxxx> · Wed, 24 Sep 2008 23:12:17 +0300 (EEST)

On Wed, 24 Sep 2008, David Stevens wrote:

netdev-owner@xxxxxxxxxxxxxxx wrote on 09/24/2008 04:20:48 AM:

On Wed, 24 Sep 2008, Pekka Savola wrote:

[psavola@lapps ~]$ more /proc/net/igmp
Idx   Device    : Count Querier   Group    Users Timer   Reporter
1   lo        :     0      V3
            010000E0     1 0:00000000      0
2   eth0      :     2      V3
            010000E0     1 0:00000000      0
3   wmaster0  :     3      V3
            010000E0     1 0:00000000      0
4   wlan0     :     3      V3
             010000E0     1 0:00000000      0

(The header and the fields seem to be a little off in the output..)

[psavola@lapps ~]$ netstat -gn | grep eth0
eth0            1      224.0.0.1
eth0            1      ff02::1

Another observation here:  the "Count" field appears to correspond to
'netstat -gn | wc -l' output.  But this includes both IPv4 and IPv6
groups.  Is this intentional?  Shouldn't this only count the v4
entries, just like /proc/net/igmp6 only includes v6 entries?

I'm guessing this is Alan Cox's code, but it's at least 8 years
old, so I'm not sure original intent is easy to establish. :-)

I agree it'd be a good idea to separate the counts. Are you
planning to do a patch?

I'm less than familiar with the code in question and not best placed 

to work on this, so if you (or someone else) would be 

interested/willing to do this, great.  If nothing happens, I may need 

to reconsider my options..

--
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html