[Python] Why is tcpdump on my Mininet router not capturing packets sent to the router’s own...

I’m working on a Mininet topology where I have one router (r1) connected to four hosts (h1, h2, h3, and h4) in two subnets: •h1 and h3 are in the 10.0.0.0/24 subnet. •h2 and h4 are in the 192.168.0.0/24 subnet.

The router (r1) has four interfaces: •r1-eth1 for h1 (10.0.0.2) •r1-eth2 for h2 (192.168.0.2) •r1-eth3 for h3 (10.0.0.4) •r1-eth4 for h4 (192.168.0.4)

Problem: •When I use tcpdump on the router interfaces (e.g., r1-eth1, r1-eth2), packets sent to the router’s IPs (like 10.0.0.2, 192.168.0.2) are not captured. •However, packets sent to host IPs (like 10.0.0.1, 192.168.0.1) are captured without any issues.

How can I make the router (r1) in Mininet actually forward packets destined for its own IPs through the physical interfaces so that they are visible in tcpdump?

•I expect packets sent to the router’s IPs (like 10.0.0.2, 192.168.0.2) to appear in the tcpdump output on the corresponding interfaces (r1-eth1, r1-eth2).

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