Hello,
On Thu, 17 Feb 2011, Bart Kus wrote:
Hello Experts,
With 00:04:23:bb:18:56 being a Linux box, it gets a ping request from a
network device:
05:50:50.393373 00:0c:db:b5:b7:00 (oui Unknown) > 00:04:23:bb:18:56 (oui
Unknown), ethertype IPv4 (0x0800), length 60: 172.20.11.3 > 192.168.70.1:
ICMP echo request, id 43981, seq 1, length 24
Before replying (even though it could, since it has the MAC as part of the
ping request) it decides to query for the MAC based on source IP of the
original ping request:
05:50:50.402347 00:04:23:bb:18:56 (oui Unknown) > Broadcast, ethertype ARP
(0x0806), length 42: Request who-has 172.20.11.3 tell 192.168.70.1, length 28
The tell section indicates to "tell 192.168.70.1", but the interface on which
this came in has an IP of 172.20.11.1. 192.168.70.1 is another IP on the
Linux router, on a different interface.
Shouldn't the ARP request say "tell 172.20.11.1" instead given ARP is an
ethernet protocol, incapable of routing to 192.168.70.1? The reply to this
broadcast never comes back from the other network device due to the weird
"tell 192.168.70.1" being there. The end result is complete ping loss.
May be what you need is to set on Linux box
/proc/.../arp_announce to 1 or 2. Check
Documentation/networking/ip-sysctl.txt for more info.
Regards
--
Julian Anastasov <ja@xxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-net" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
