Capture problems with Intel quad cards?

Mr. James W. Laferriere babydr at
Mon Feb 16 18:39:18 UTC 2009

 	Hello John ,

On Sun, 15 Feb 2009, John A. Kilpatrick wrote:
> Has anyone had problems with using current Intel quad ethernet cards for 
> packet capture?  As a proof-of-concept test we bought an Intel PWLA8494GT and 
> hooked it up to some Network Critical taps.  There was a very strange issue 
> with corruption of the captured packets.  The *only* issue (but it's a big 
> one) is that the source IP on some captured packets is munged.  As far as I 
> can tell that's the *only* issue with the packet captures - no other data is 
> corrupted.
> Oh, and to rule out other issues:
> 1.  Corruption seen both when using network taps and when using a port
> span/mirror (so it's not the taps).
> 2.  Corruption *not* seen using the on-board broadcom nics of the test
> host (so it's not the box).
> So I'm pretty sure we narrowed it down to the card.  We tried the card in
> an indentical host and saw the same problems.
> I thought it might be a driver issue - I tried both gentoo and FreeBSD (not 
> sure how different the drivers are) just to see if it mattered at all and it 
> didn't.  Much googling didn't show this to be a known issue - just wondering 
> if anyone else has seen it?  Other recommendations welcome - the next step 
> is, I suppose, a broadcom-based PCI-X card.  (I've got some old pizza boxes 
> I'm trying to repurpose as network probes.)
> Thanks,
> John
 	Does this device provide 4 unique mac-addresses ?  Reason for the 
question is some old(I mean old) multiport cards presented a single mac-address 
because the were driven by a single 'Switch chip' .  Just a thought .  I've been 
looking a the Intel site gandering over the overview & have not seen anything to 
relieve my concern .  But one Hopes they have learned not to create themselves 
such a problem .

 		Hth ,  JimL
| James   W.   Laferriere | System    Techniques | Give me VMS     |
| Network&System Engineer | 2133    McCullam Ave |  Give me Linux  |
| babydr at | Fairbanks, AK. 99701 |   only  on  AXP |

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