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wavezhang/change_pod_cidr.sh

Last active June 27, 2019 08:18
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Revisions

  1. wavezhang revised this gist Jun 27, 2019. No changes.
  2. wavezhang created this gist Jul 24, 2018.
    39 changes: 39 additions & 0 deletions change_pod_cidr.sh
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    #!/bin/bash

    POD_CIDR="100.64.0.0\/14"
    CTL_MGR_CFG=/etc/kubernetes/manifests/kube-controller-manager.yaml

    kubectl apply -f https://docs.projectcalico.org/v3.1/getting-started/kubernetes/installation/hosted/calicoctl.yaml

    echo "Updating kube controller manager params..."
    sed -i "s/--cluster-cidr=.*/--cluster-cidr=$POD_CIDR/g" $CTL_MGR_CFG

    echo "Updating kubeadm configmap..."
    kubectl get configmap kubeadm-config -o yaml -n kube-system | sed "s/ clusterCIDR: 192.168.0.0\/16/ clusterCIDR: $POD_CIDR/g" | sed "s/ podSubnet: 192.168.0.0\/16/ podSubnet: $POD_CIDR/g" | kubectl apply -f -

    echo "Updating kube-proxy configmap..."
    kubectl get configmap kube-proxy -o yaml -n kube-system | sed "s/ clusterCIDR: 192.168.0.0\/16/ clusterCIDR: $POD_CIDR/g" | kubectl apply -f -

    echo "Recreating kube-proxy pod..."
    kubectl get pod -n kube-system | grep kube-proxy | awk '{print $1}' | xargs -r -L1 kubectl delete pod -n kube-system

    echo "update calico config"
    kubectl get daemonsets -n kube-system calico-node -o yaml | sed "s/value: 192.168.0.0\/16/value: $POD_CIDR/g" | kubectl apply -f -

    echo "Recreating calico-node pod..."
    kubectl get pod -n kube-system | grep calico-node | awk '{print $1}' | xargs -r -L1 kubectl delete pod -n kube-system

    echo "Updating nodes..."
    kubectl get nodes -o yaml | sed "/podCIDR: 192.168./d" > nodes.yaml
    kubectl delete -f nodes.yaml
    kubectl create -f nodes.yaml

    echo "Updating calico data ..."
    kubectl exec -ti -n kube-system calicoctl -- /calicoctl get ipPool default-ipv4-ippool -o yaml | sed "s/ cidr: 192.168.0.0\/16/ cidr: $POD_CIDR/g" > ippool.yaml
    kubectl exec -ti -n kube-system calicoctl -- /calicoctl delete ipPool default-ipv4-ippool
    cat ippool.yaml | kubectl exec -ti -n kube-system calicoctl -- /calicoctl apply -f -

    echo "Updating old pod..."
    kubectl get pod --all-namespaces -o wide | grep "192.168" | awk '{print $2" -n "$1}' | xargs -r -L1 kubectl delete pod

    kubectl get pod --all-namespaces -owide -w