Merge pull request #2886 from weaveworks/lock-kubeadm-version

Lock kubeadm's Kubernetes version

.lintignore

@@ -16,7 +16,6 @@ prog/weave-kube/launch.sh
 prog/weaveexec/symlink
 test/*_test.sh
 test/600_proxy_docker_py.sh
-test/840_*
 test/assert.sh
 test/config.sh
 test/gce.sh

test/840_weave_kube_3_test.sh

@@ -24,7 +24,11 @@ tear_down_kubeadm
 docker_on $HOST1 run --rm --privileged --net=host --entrypoint=/usr/sbin/ipset weaveworks/weave-npc create test_840_ipset bitmap:ip range 192.168.1.0/24 || true
 docker_on $HOST1 run --rm --privileged --net=host --entrypoint=/usr/sbin/ipset weaveworks/weave-npc add test_840_ipset 192.168.1.11
 
-run_on $HOST1 "sudo systemctl start kubelet && sudo kubeadm init --token=$TOKEN"
+# kubeadm init upgrades to latest Kubernetes version by default, therefore we try to lock the version using the below option:
+k8s_version="$(run_on $HOST1 "kubelet --version" | grep -oP "(?<=Kubernetes )v[\d\.\-beta]+")"
+k8s_version_option="$([[ "$k8s_version" > "v1.6" ]] && echo "kubernetes-version" || echo "use-kubernetes-version")"
+
+run_on $HOST1 "sudo systemctl start kubelet && sudo kubeadm init --$k8s_version_option=$k8s_version --token=$TOKEN"
 run_on $HOST2 "sudo systemctl start kubelet && sudo kubeadm join --token=$TOKEN $HOST1IP"
 run_on $HOST3 "sudo systemctl start kubelet && sudo kubeadm join --token=$TOKEN $HOST1IP"