[CentOS] arp corrupted

Ralph Angenendt ra+centos at br-online.de
Mon Oct 22 09:31:59 UTC 2007


Bobby wrote:
> On Sunday 21 October 2007 14:11:15 Ralph Angenendt wrote:
>> Can you look with tcpdump what happens on the network?
>>
>> tcpdump -i any arp
>>
>> should do that.
> 
> That's what I've been doing for a couple of days. The requests goes 
> unanswered. I'm monitoring all the NICs and can follow it in real time.
> 
> I sniffed it to see if there were any clues but all is totally standard IP. 

But through which interfaces did the arp requests arrive *before*
turning on arp_filter and on which interfaces do they arrive *after*
setting arp_filter? 

If both cards are on the same switch and arp_filtering is turned off,
any of the two interfaces will answer arp requests for both cards, as
both requests go to an interface, which is local to the machine.

Turning on arp_filtering, each interface will only answer requests
directed at that interface. 

Can you send some sniffing output *before* and *after* changing the
setting? Is there anything strange in dmesg?

Cheers,

Ralph
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