Use cluster-cidr from kube-controller-manager.yaml (#5248)

Instead of using the in-cluster kubeadm config which sometimes? loses
the configured podSubnet, instead pull the podSubnet from the
kube-controller-manager static manifest. this should prevent an issue
where kurl sometimes resets the podSubnet on upgrade.

Author: hedge-sparrow

addons/flannel/0.20.0/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.20.1/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.20.2/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.21.0/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.21.1/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.21.2/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.21.3/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.21.4/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.21.5/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }
 

addons/flannel/0.22.0/install.sh

@@ -162,7 +162,7 @@ function flannel_init_pod_subnet() {
     cp "$src/kubeadm.yaml" "$DIR/kustomize/kubeadm/init-patches/flannel.yaml"
 
     if commandExists kubectl; then
-        EXISTING_POD_CIDR=$(kubectl -n kube-system get cm kubeadm-config -oyaml 2>/dev/null | grep podSubnet | awk '{ print $NF }')
+        EXISTING_POD_CIDR=$(awk -F '=' '/--cluster-cidr/{print $2}' /etc/kubernetes/manifests/kube-controller-manager.yaml 2>/dev/null)
     fi
 }