Kubernetes with fcos the hard way

k8s_fcos_setup.sh

#enable crio repo
cat <<EOF | tee /etc/yum.repos.d/cri-o.repo
[cri-o]
name=CRI-O
baseurl=https://pkgs.k8s.io/addons:/cri-o:/stable:/$CRIO_VERSION/rpm/
enabled=1
gpgcheck=1
gpgkey=https://pkgs.k8s.io/addons:/cri-o:/stable:/$CRIO_VERSION/rpm/repodata/repomd.xml.key
EOF

rpm-ostree install crictl crio conntrack-tools
systemctl reboot

#crio network (see https://kubernetes.io/docs/setup/production-environment/container-runtimes/)
sudo sh -c 'echo "br_netfilter" > /etc/modules-load.d/br_netfilter.conf
cat <<EOF | sudo tee /etc/sysctl.d/99-kubernetes-cri.conf
net.bridge.bridge-nf-call-iptables  = 1
net.ipv4.ip_forward                 = 1
net.bridge.bridge-nf-call-ip6tables = 1
EOF

#install kubeadm (https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/install-kubeadm/)
DOWNLOAD_DIR=/usr/local/bin
cd $DOWNLOAD_DIR
RELEASE="$(curl -sSL https://dl.k8s.io/release/stable.txt)"
ARCH="amd64"
sudo curl -L --remote-name-all https://dl.k8s.io/release/${RELEASE}/bin/linux/${ARCH}/{kubeadm,kubelet}          
sudo curl -L --remote-name-all https://dl.k8s.io/release/${RELEASE}/bin/linux/${ARCH}/{kubeadm,kubelet}
sudo chmod +x {kubeadm,kubelet}


RELEASE_VERSION="v0.4.0"
curl -sSL "https://raw.githubusercontent.com/kubernetes/release/${RELEASE_VERSION}/cmd/kubepkg/templates/latest/deb/kubelet/lib/systemd/system/kubelet.service" | sed "s:/usr/bin:${DOWNLOAD_DIR}:g" | sudo tee /etc/systemd/system/kubelet.service
sudo mkdir -p /etc/systemd/system/kubelet.service.d
curl -sSL "https://raw.githubusercontent.com/kubernetes/release/${RELEASE_VERSION}/cmd/kubepkg/templates/latest/deb/kubeadm/10-kubeadm.conf" | sed "s:/usr/bin:${DOWNLOAD_DIR}:g" | sudo tee /etc/systemd/system/kubelet.service.d/10-kubeadm.conf

#enable services
systemctl enable --now kubelet
systemctl enable --now crio

#prepare/tweak config
kubeadm config print init-defaults >kubeadm-init.yaml 
#api server ip
sed -i "s/advertiseAddress: 1.2.3.4/advertiseAddress: $(hostname -I|cut -f1 -d ' ')/g"

#flex volume dir must be writable
sed -i 's/controllerManager: {}/controllerManager: {"extraArgs": {"flex-volume-plugin-dir": "/var/lib/kubelet/volumeplugins"}}/g'
#cgroup systemd
echo "apiVersion: kubelet.config.k8s.io/v1beta1
kind: KubeletConfiguration
cgroupDriver: systemd" >> kubeadm-init.yaml

#init
kubeadm init --config=./kubeadm-init.yaml


#remove taint
kubectl taint nodes --all node-role.kubernetes.io/master-