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Should an arp ever be for a IP on another network

0

From what I understand if things are configured correctly I shouldn't see an ARP to a Target IP on a different subnet.

Since it should know the MAC address it should use is the default GW.

Something may be misconfigured, but I'm not seeing it yet.

I'll attach the network trace.

But my question is whether I should be seeing an ARP for an IP on another subnet?

asked 31 Jul '15, 14:23

gipper's gravatar image

gipper
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accept rate: 0%

I uploaded trace.

See frame 27.

https://www.cloudshark.org/captures/d8c1f95f6e29

(31 Jul '15, 14:30) gipper

One Answer:

2

The most probably reason for such behaviour is a misconfigured Subnetmask at the sender. In this case: 52.97.224.112.

answered 31 Jul '15, 16:44

Christian_R's gravatar image

Christian_R
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accept rate: 16%

agree, subnet mask is wrong on the node sending the ARP. It thinks it can reach the destination directly without the default gateway. Easily fixed by correcting the subnet mask setting of that node.

(01 Aug '15, 10:05) Jasper ♦♦