Master:

default via 172.31.1.1 dev eth0
172.31.1.1 dev eth0 scope link

Worker1:

default via 172.31.1.1 dev eth0
10.42.0.0/24 via 10.42.0.0 dev flannel.1 onlink
10.42.1.0/24 via 10.42.1.0 dev flannel.1 onlink
172.31.1.1 dev eth0 scope link

Worker2:

default via 172.31.1.1 dev eth0
10.42.1.0/24 via 10.42.1.0 dev flannel.1 onlink
10.42.2.0/24 via 10.42.2.0 dev flannel.1 onlink
172.31.1.1 dev eth0 scope link

Worker3:

default via 172.31.1.1 dev eth0
10.42.0.0/24 via 10.42.0.0 dev flannel.1 onlink
10.42.1.0/24 dev cni0 proto kernel scope link src 10.42.1.1
10.42.2.0/24 via 10.42.2.0 dev flannel.1 onlink
172.31.1.1 dev eth0 scope link