Re: route problem

[Eric Dumazet <eric.dumazet@gmail.com>]

Le mercredi 18 janvier 2012 à 14:47 +0530, Prashant Batra (prbatra) a
écrit :
> Hi,
> 
> I have added a route for an external ip via a gateway which is available
> on the same machine.
> I want to capture the packets going to this external IP using PF_PACKET
> socket.
> 
> #route 
> Destination     Gateway         Genmask         Flags Metric Ref    Use
> Iface
> 192.168.101.0   *               255.255.255.0   U     0      0        0
> eth1
> 172.16.60.0     192.168.101.10  255.255.255.0   UG    0      0        0
> eth1
> 
> So, when a packet is sent to 172.16.60.*, kernel should send arp request
> for this gw IP 192.168.101.10. As gw IP is locally reachable, 
> It should send its mac address in arp-response and kernel should send
> the packet via that interface.
> 
> But what I am seeing is that instead of asking the gateway IP, kernel
> sends a arp request for destingation ip(172.16.60.*)
> 
> #tcpdump -I eth1
> 04:12:45.334966 arp who-has 172.16.60.2 tell 192.168.101.20
> 04:12:46.334839 arp who-has 172.16.60.2 tell 192.168.101.20
> 04:12:48.334584 arp who-has 172.16.60.2 tell 192.168.101.20
> 04:12:49.334457 arp who-has 172.16.60.2 tell 192.168.101.20
> 04:12:50.335329 arp who-has 172.16.60.2 tell 192.168.101.20
> 04:12:52.335075 arp who-has 172.16.60.2 tell 192.168.101.20
> 04:12:53.334947 arp who-has 172.16.60.2 tell 192.168.101.20
> 04:12:54.334821 arp who-has 172.16.60.2 tell 192.168.101.20
> 

Redirect problem ?

Please post 

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