6. Demo: VLANs inside a Linux machine

Topology

Expected result

PC1 & PC2 are on the same VLAN, they can communicate each other

PC1 & PC3 are on different VLANs, thay CANNOT see each other

Configuration

sudo ip netns add pc1 sudo ip netns add pc2 sudo ip netns add pc3 sudo ip netns add pc4 sudo brctl addbr vSwitch sudo ip link add eth1 type veth peer name eth5 sudo ip link add eth2 type veth peer name eth6 sudo ip link add eth3 type veth peer name eth7 sudo ip link add eth4 type veth peer name eth8    sudo ip link set eth1 netns pc1 sudo ip link set eth2 netns pc2 sudo ip link set eth3 netns pc3 sudo ip link set eth4 netns pc4 sudo brctl addif vSwitch eth5 sudo brctl addif vSwitch eth6 sudo brctl addif vSwitch eth7 sudo brctl addif vSwitch eth8    sudo ip netns exec pc1 ip link add link eth1 name vlan type vlan id 10 sudo ip netns exec pc2 ip link add link eth2 name vlan type vlan id 10 sudo ip netns exec pc3 ip link add link eth3 name vlan type vlan id 20 sudo ip netns exec pc4 ip link add link eth4 name vlan type vlan id 20    sudo ip netns exec pc1 ip addr add 10.0.0.1/24 dev vlan sudo ip netns exec pc2 ip addr add 10.0.0.2/24 dev vlan sudo ip netns exec pc3 ip addr add 10.0.0.3/24 dev vlan sudo ip netns exec pc4 ip addr add 10.0.0.4/24 dev vlan    sudo ip netns exec pc1 ip link set eth1 up sudo ip netns exec pc2 ip link set eth2 up sudo ip netns exec pc3 ip link set eth3 up sudo ip netns exec pc4 ip link set eth4 up sudo ip link set vSwitch up sudo ip link set eth5 up sudo ip link set eth6 up sudo ip link set eth7 up sudo ip link set eth8 up    sudo ip netns exec pc1 ip link set vlan up sudo ip netns exec pc2 ip link set vlan up sudo ip netns exec pc3 ip link set vlan up sudo ip netns exec pc4 ip link set vlan up    sudo ip netns exec pc1 ping 10.0.0.2 sudo ip netns exec pc1 ping 10.0.0.3 sudo ip netns exec pc1 ping 10.0.0.4   sudo ip netns exec pc4 ping 10.0.0.1 sudo ip netns exec pc4 ping 10.0.0.2 sudo ip netns exec pc4 ping 10.0.0.3

Result

vdkmai@Ubuntu32bit:~$ sudo ip netns exec pc1 ping 10.0.0.2 PING 10.0.0.2 (10.0.0.2) 56(84) bytes of data. 64 bytes from 10.0.0.2: icmp_req=1 ttl=64 time=0.040 ms 64 bytes from 10.0.0.2: icmp_req=2 ttl=64 time=0.066 ms ^C --- 10.0.0.2 ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 999ms rtt min/avg/max/mdev = 0.040/0.053/0.066/0.013 ms vdkmai@Ubuntu32bit:~$ sudo ip netns exec pc1 ping 10.0.0.3 PING 10.0.0.3 (10.0.0.3) 56(84) bytes of data. ^C --- 10.0.0.3 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1009ms vdkmai@Ubuntu32bit:~$ sudo ip netns exec pc1 ping 10.0.0.4 PING 10.0.0.4 (10.0.0.4) 56(84) bytes of data. ^C --- 10.0.0.4 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1008ms vdkmai@Ubuntu32bit:~$ sudo ip netns exec pc4 ping 10.0.0.1 PING 10.0.0.1 (10.0.0.1) 56(84) bytes of data. ^C --- 10.0.0.1 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1006ms vdkmai@Ubuntu32bit:~$ sudo ip netns exec pc4 ping 10.0.0.2 PING 10.0.0.2 (10.0.0.2) 56(84) bytes of data. ^C --- 10.0.0.2 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1001ms vdkmai@Ubuntu32bit:~$ sudo ip netns exec pc4 ping 10.0.0.3 PING 10.0.0.3 (10.0.0.3) 56(84) bytes of data. 64 bytes from 10.0.0.3: icmp_req=1 ttl=64 time=0.048 ms 64 bytes from 10.0.0.3: icmp_req=2 ttl=64 time=0.069 ms ^C --- 10.0.0.3 ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 999ms rtt min/avg/max/mdev = 0.048/0.058/0.069/0.013 ms

Commands to reset configuration

sudo ip netns del pc1 sudo ip netns del pc2 sudo ip netns del pc3 sudo ip netns del pc4 sudo ip link set vSwitch down sudo brctl delbr vSwitch

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