Howto kubernetes archlinux

download latest archlinux cloud image:

wget https://linuximages.de/openstack/arch/arch-openstack-LATEST-image-bootstrap.qcow2

make sure we have libguestfs installed:

pacman -S libguestfs guestfs-tools

resize image:

cp arch-openstack-LATEST-image-bootstrap.qcow2 arch-openstack-LATEST-image-bootstrap_100G.qcow2
qemu-img resize arch-openstack-LATEST-image-bootstrap_100G.qcow2 +99G

expand image:

virt-resize --expand /dev/sda1 arch-openstack-LATEST-image-bootstrap.qcow2 arch-openstack-LATEST-image-bootstrap_100G.qcow2

change password:

virt-sysprep -a arch-openstack-LATEST-image-bootstrap_100G.qcow2 -q --root-password password:vidalinux

uninstall cloud-init:

virt-sysprep -a arch-openstack-LATEST-image-bootstrap_100G.qcow2 --run-command "pacman -R cloud-init --noconfirm"

on centos copy the image to this directory:

cd /var/lib/libvirt/images/

configure hostname:

hostnamectl set-hostname archlinux.ovoxcloud.com

configure /etc/hosts:

cat > /etc/hosts << EOF
127.0.0.1 localhost
192.168.24.10 archlinux.ovoxcloud.com
EOF

network configuration:

ip addr add 192.168.24.10/24 dev eth0
ip route add default via 192.168.24.254
echo "nameserver 4.2.2.1" > /etc/resolv.conf

stop and disable systemd-resolved:

systemctl disable systemd-resolved && systemctl stop systemd-resolved

install editor:

pacman -Syu nano --noconfirm

edit /etc/ssh/sshd_config:

PasswordAuthentication yes
PermitRootLogin yes

restart sshd service:

systemctl restart sshd

create virtual machine on virt-manager then update the os:

pacman -Syuu --noconfirm

install packages:

pacman -Sy --noconfirm curl vim screen nano net-tools bind-tools containerd networkmanager ebtables ethtool wget unzip socat cni-plugins conntrack-tools cri-o

add the following config to crio:

cat > 00-plugin-dir.conf << EOF 
[crio.network]
plugin_dirs = [
  "/opt/cni/bin/",
]
EOF

start and enable cri-o:

systemctl enable crio && systemctl start crio

start and enable containerd:

systemctl enable containerd && systemctl start containerd

configure networkmanager:

systemctl start NetworkManager && systemctl enable NetworkManager
nmcli con del eth0
nmcli con del Wired\ connection\ 1
nmcli con add con-name eth0 ipv4.method manual type ethernet ifname eth0 ipv4.addresses 192.168.24.10/24 ipv4.gateway 192.168.24.254 ipv4.dns 4.2.2.1,4.2.2.2 autoconnect yes

installing CNI:

CNI_VERSION="v1.3.0"
mkdir -p /opt/cni/bin
curl -L "https://github.com/containernetworking/plugins/releases/download/${CNI_VERSION}/cni-plugins-linux-amd64-${CNI_VERSION}.tgz" | tar -C /opt/cni/bin -xz

installing CRI:

CRICTL_VERSION="v1.27.0"
mkdir -p /opt/bin
curl -L "https://github.com/kubernetes-sigs/cri-tools/releases/download/${CRICTL_VERSION}/crictl-${CRICTL_VERSION}-linux-amd64.tar.gz" | tar -C /opt/bin -xz

installing kubeadm, kubelet, kubectl

RELEASE="$(curl -sSL https://dl.k8s.io/release/stable.txt)"
mkdir -p /opt/bin
cd /opt/bin
curl -L --remote-name-all https://storage.googleapis.com/kubernetes-release/release/${RELEASE}/bin/linux/amd64/{kubeadm,kubelet,kubectl}
chmod +x {kubeadm,kubelet,kubectl}
curl -sSL "https://raw.githubusercontent.com/kubernetes/release/master/cmd/kubepkg/templates/latest/deb/kubelet/lib/systemd/system/kubelet.service" | sed "s:/usr/bin:/opt/bin:g" > /etc/systemd/system/kubelet.service
mkdir -p /etc/systemd/system/kubelet.service.d
curl -sSL "https://raw.githubusercontent.com/kubernetes/release/master/cmd/kubepkg/templates/latest/deb/kubeadm/10-kubeadm.conf" | sed "s:/usr/bin:/opt/bin:g" > /etc/systemd/system/kubelet.service.d/10-kubeadm.conf

create symbolic links for executables:

for u in $(ls|grep -v bins > bins && sed 'H;1h;$!d;x;s/\n/ /g' bins); do ln -s /opt/bin/$u /usr/local/bin/$u &&  chmod +x /usr/local/bin/$u; done

fix kernel on arch:

pacman -Sy linux
grub-mkconfig -o /boot/grub/grub.cfg

load kernel module:

modprobe br_netfilter

add the following file to load this module at boot:

cat > /etc/modprobe.d/netfilter.conf << EOF
br_netfilter
EOF

ensure net.bridge.bridge-nf-call-iptables is set to 1 in your sysctl config:

cat <<EOF > /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF
sysctl --system

start kube cluster:

kubeadm init --pod-network-cidr 10.234.0.0/16 --apiserver-advertise-address=0.0.0.0 --cri-socket /var/run/crio/crio.sock --node-name archlinux.ovoxcloud.com

to start using your cluster, you need to run the following as a regular user:

mkdir -p $HOME/.kube
cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
chown $(id -u):$(id -g) $HOME/.kube/config

watch kubelet lot for errors:

journalctl -u kubelet -f

install calico for pod networking:

kubectl create -f https://raw.githubusercontent.com/projectcalico/calico/v3.26.0/manifests/tigera-operator.yaml
kubectl create -f https://raw.githubusercontent.com/projectcalico/calico/v3.26.0/manifests/custom-resources.yaml

untaint the master so you can run pods

kubectl taint nodes archlinux.ovoxcloud.com node.kubernetes.io/not-ready:NoSchedule-

verify everthing is ok:

kubectl get nodes

if everything is ok you got this message:

NAME                      STATUS   ROLES    AGE     VERSION
kubenode1.ovoxcloud.com   Ready    master   3m45s   v1.18.4

set up nginx-ingress:

kubectl apply -f mandatory.yaml
kubectl -n ingress-nginx patch deployment nginx-ingress-controller --patch="$(<nginx-host-networking.yaml)"
kubectl apply -f service-nodeport.yaml

use base64 command to encrypt ssl certificates:

cat privkey.pem |base64 -w 0
cat fullchain.pem |base64 -w 0

change name space:

kubectl config set-context --current --namespace=seafile-app

display pods running in current namespace:

kubectl get pods

show all pods running in all namespaces:

kubectl get pods --all-namespaces

copy certifcates to seafile data ssl directory:

cp privkey.pem /static/kube/data/seafile/ssl/seafile.domain.com.key
cp fullchain.pem /static/kube/data/seafile/ssl/seafile.domain.com.crt

deploy application using yaml:

kubectl create -f seafile.yaml

if you need to enter a container via shell use:

kubectl exec -it seafile-srv-697c787f5c-px7cw -- /bin/bash

show container log:

kubectl logs seafile-srv-697c787f5c-px7cw

renew certificates

verify certificates:

kubeadm alpha certs check-expiration

renew all certificates:

kubeadm alpha certs renew all

replace the config:

cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

references

[latest version]

• https://github.com/kubernetes/release

[cni latest version]

• https://github.com/containernetworking/plugins/releases

[cri-tools latest version]

• https://github.com/kubernetes-sigs/cri-tools