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bmegli/route_A_through_B_to_C.md

Created March 17, 2024 13:18
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route traffic from A over B network interfaces to C
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route_A_through_B_to_C.md

Scenario

# B has 2 network interaces, A reachable through one, C reachable through other
# We want A to C communiation (over B)
A----B----C

Ad-hoc solution

# on A 
ip route add C_SUBNET/24 via B_IP

# e.g. ip route add 192.168.1.0/24 via 192.168.0.B_ADDRESS
# on B
sysctl -w net.ipv4.ip_forward=1
sudo iptables -t nat -A POSTROUTING -s A_SUBNET/24 -j MASQUERADE

# e.g. sudo iptables -t nat -A POSTROUTING -s 192.168.0.0/24 -j MASQUERADE
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