In Conntrack SNAT, when a router g/w is cleared traffic is dropped for other routers.

Step to reproduce.
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In a single node setup
1)Create two tenant n/w net1 and net2 and a external n/w
2)Create two routers and one n/w to each router and set the g/w
3)Clear on of the router g/w for net1
4)Try to ping the external n/w from the DHCP NS of net2.

Expected output
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External n/w should be reachable.

Actual output
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External n/w is not reachable.