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* Re: Any changes in Multicast code between 2.4.20 and 2.4.22/23 ?
@ 2004-01-06 11:11 Martin Knoblauch
  0 siblings, 0 replies; 6+ messages in thread
From: Martin Knoblauch @ 2004-01-06 11:11 UTC (permalink / raw)
  To: David Stevens; +Cc: linux-kernel, linux-net

[-- Attachment #1: Type: text/plain, Size: 893 bytes --]

>> Second, can you send me a tcpdump-format packet trace
>> (preferrably
>> only the multicast traffic, and as small as you can make it)?
>
>What exactely do you want to see? On which box should I run tcpdump?
>Which options (I'm not that deep into network debugging :-)?

 so, I append two traces from "tcpdump -i eth1 multicast". "good" is
from the 2.4.20.-18.7smp kernel, "bad" is from 2.4.22.

 What is interesting from a first look is the fact that the 2.4.22
kernel seems to drop/miss packets from outside that go to a
nonpriviledged port on the multicast group. Ganglia uses port 8649. In
the "bad" case, packets for "239.2.11.71.8649" only come from the local
box. Does this ring any bells for "tg3" or the networking code?

Cheers
Martin

=====
------------------------------------------------------
Martin Knoblauch
email: k n o b i AT knobisoft DOT de
www:   http://www.knobisoft.de

[-- Attachment #2: bad.tcpdump --]
[-- Type: application/octet-stream, Size: 9596 bytes --]

[-- Attachment #3: good.tcpdump --]
[-- Type: application/octet-stream, Size: 8612 bytes --]

^ permalink raw reply	[flat|nested] 6+ messages in thread
* Re: Any changes in Multicast code between 2.4.20 and 2.4.22/23 ?
@ 2004-01-06 13:17 Martin Knoblauch
  0 siblings, 0 replies; 6+ messages in thread
From: Martin Knoblauch @ 2004-01-06 13:17 UTC (permalink / raw)
  To: linux-kernel

>Can you look on the adjacent multicast router(s) and see if your host
is
>listed as a group member? Or is this done with just a flat IP network
>(one subnet)?
Lawrence,

 all in one subnet.

Martin
 
>On Mon, 2004-01-05 at 21:21, Martin Knoblauch wrote:
>> --- David Stevens <dlstevens@xxxxxxxxxx> wrote:
>> >


=====
------------------------------------------------------
Martin Knoblauch
email: k n o b i AT knobisoft DOT de
www:   http://www.knobisoft.de

^ permalink raw reply	[flat|nested] 6+ messages in thread
[parent not found: <OF82F2C5E5.10FE707F-ON88256E12.00701FFA@us.ibm.com>]
* Any changes in Multicast code between 2.4.20 and 2.4.22/23 ?
@ 2004-01-05 15:02 Martin Knoblauch
  0 siblings, 0 replies; 6+ messages in thread
From: Martin Knoblauch @ 2004-01-05 15:02 UTC (permalink / raw)
  To: linux-net; +Cc: linux-kernel

>Hi,
>
>besides wishing everybody a Happy new Year 2004, I have one question.
>Have there been any changes in the multicast handling between 2.4.20
>and 2.4.22/23? Maybe specific to the "tg3" driver?
>
>Reason for my question is that the Ganglia monitoring toolkit stopped
>working with 2.4.22/23 kernels. Apparently mulicatst get sent, but
>nothing is received.
>
>Any ideas?
>
>
>Thanks
>Martin

Hi,

 just realized the massive changes between 21 and 22. At least that is
answered :-) Question remains why no MC packets arrive in 2.4.22 and
later (checked with tcpdump). Is there anything that one has to enable
when running a newer kernel?

 One diffeernce is the output of "cat /proc/net/igmp". On my 2.4.20
kernel it looks like:

[qx29340@lpsdm16 ~]$ cat /proc/net/igmp
Idx     Device    : Count Querier       Group    Users Timer  Reporter
1       lo        :     0      V2
                                010000E0     1 0:F63C1223            0
2       eth0      :     1      V2
                                010000E0     1 0:F63C1225            0
3       eth1      :     2      V2
                                470B02EF     1 0:F63C2428            1
                                010000E0     1 0:F63C1225            0

 While on 2.4.22/23 it looks like:

qx29340@lpsdm20 linux-2.4.23-1-msc]$ cat /proc/net/igmp
Idx     Device    : Count Querier       Group    Users Timer Reporter
1       lo        :     0      V2
                                010000E0     1 0:FFFE5D5D           0
2       eth0      :     1      V2
                                010000E0     1 0:FFFE5D5D           0
3       eth1      :     2      V2
                                470B02EF     1 0:FFFF8D5D           0
                                010000E0     1 0:FFFE5D5D           0


 The difference seems to be the "reporter" flag for the 470B02EF
multicast group, which is exactely the adrress Ganglia uses.

Any ideas
Cheers
Martin
PS: Moved to linux-net

=====
------------------------------------------------------
Martin Knoblauch
email: k n o b i AT knobisoft DOT de
www:   http://www.knobisoft.de

^ permalink raw reply	[flat|nested] 6+ messages in thread
* Any changes in Multicast code between 2.4.20 and 2.4.22/23 ?
@ 2004-01-05 10:39 Martin Knoblauch
  0 siblings, 0 replies; 6+ messages in thread
From: Martin Knoblauch @ 2004-01-05 10:39 UTC (permalink / raw)
  To: linux-kernel

Hi,

 besides wishing everybody a Happy new Year 2004, I have one question.
Have there been any changes in the multicast handling between 2.4.20
and 2.4.22/23? Maybe specific to the "tg3" driver?

 Reason for my question is that the Ganglia monitoring toolkit stopped
working with 2.4.22/23 kernels. Apparently mulicatst get sent, but
nothing is received.

 Any ideas?

Thanks
Martin

=====
------------------------------------------------------
Martin Knoblauch
email: k n o b i AT knobisoft DOT de
www:   http://www.knobisoft.de

^ permalink raw reply	[flat|nested] 6+ messages in thread
end of thread, other threads:[~2004-01-06 13:17 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2004-01-06 11:11 Any changes in Multicast code between 2.4.20 and 2.4.22/23 ? Martin Knoblauch
  -- strict thread matches above, loose matches on Subject: below --
2004-01-06 13:17 Martin Knoblauch
     [not found] <OF82F2C5E5.10FE707F-ON88256E12.00701FFA@us.ibm.com>
2004-01-06  2:21 ` Martin Knoblauch
2004-01-06 12:59   ` Lawrence MacIntyre
2004-01-05 15:02 Martin Knoblauch
2004-01-05 10:39 Martin Knoblauch

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