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K3S Install

Install​

caution
  • 如果 install 用了 https_proxy, 会被写入到 /etc/rancher/k3s/k3s.env
# 下载到临时目录进行安装
curl -sfL https://get.k3s.io | INSTALL_K3S_SKIP_START=true INSTALL_K3S_SKIP_ENABLE=true sh -

下载不动可下载脚本自行修改镜像 GITHUB_URL=https://ghproxy.com/github.com/k3s-io/k3s/releases

curl -o k3s-install.sh https://get.k3s.io
sed '/GITHUB_URL=/a GITHUB_URL=https://ghproxy.com/github.com/k3s-io/k3s/releases' -i k3s-install.sh
INSTALL_K3S_SKIP_START=true INSTALL_K3S_SKIP_ENABLE=true bash k3s-install.sh
# AlpineLinux
sed 's/sourcex/\./g' -i /etc/init.d/k3s

# 准备
service cgroups start
rc-update add cgroups
apk add nfs-utils coreutils iptables iproute2 findutils
# 配置检查
k3s check-config

# mkdir -p /etc/rancher/k3s
# 配置
echo 'rc_ulimit="-n 1048576"' > /etc/rancher/k3s/k3s.env
cat << YAML > /etc/rancher/k3s/registries.yaml
mirrors:
  docker.io:
    endpoint:
      - https://fogjl973.mirror.aliyuncs.com
      - https://8x40wsit.mirror.aliyuncs.com
      - https://registry-1.docker.io
YAML

cat << YAML > /etc/rancher/k3s/config.yaml
# write-kubeconfig-mode: '0644'

token: $(uuidgen)
agent-token: $(uuidgen)

node-name: $(hostname)

disable:
- servicelb
- traefik

prefer-bundled-bin: true

#tls-san:
#- kube.dev.example.com

#data-dir: /data/var/k3s
YAML

k3s check-config

service k3s start
rc-update add k3s

k3s kubectl get node
k3s kubectl get events -Aw
# 取回配置
rsync --rsync-path 'sudo rsync' kube:/etc/rancher/k3s/k3s.yaml kubeconfig.yaml

# write-kubeconfig-mode: '0644'
scp kube:/etc/rancher/k3s/k3s.yaml kubeconfig.yaml

k3s-install.sh​

  • INSTALL_K3S_CHANNEL_URL https://update.k3s.io/v1-release/channels
  • 安装内容
    • /usr/local/bin/kubectl -> k3s
    • /usr/local/bin/crictl -> k3s
    • /usr/local/bin/ctr -> k3s
      • 可能已经存在 /usr/bin/ctr
    • /usr/local/bin/k3s-killall.sh
    • /usr/local/bin/k3s-uninstall.sh
    • /etc/systemd/system/k3s.service.env
    • /etc/systemd/system/k3s.service
  • 安装包 rancher-k3s-common-stable
    • k3s-selinux
  • /var/lib/rancher/k3s/data/current/bin
    • k3s
    • coreutils
    • busybox
    • slirp4netns
    • runc
    • pigz
    • nsenter
    • losetup
    • ipset
    • ip
    • find
    • ethtool
    • conntrack
    • containerd
    • containerd-shim-runc-v2
    • cni
    • check-config
    • blkid
    • aux
  • URL
    • hash
      • ${STORAGE_URL}/k3s${SUFFIX}-${INSTALL_K3S_COMMIT}.sha256sum
      • ${GITHUB_URL}/download/${VERSION_K3S}/sha256sum-${ARCH}.txt
    • binary
      • ${STORAGE_URL}/k3s${SUFFIX}-${INSTALL_K3S_COMMIT}
      • ${GITHUB_URL}/download/${VERSION_K3S}/k3s${SUFFIX}
/etc/rancher/k3s/config.yaml
write-kubeconfig-mode: '0644'

data-dir: /data/k3s

token: $(uuidgen)
agent-token: $(uuidgen)

node-name: kube-1

disable:
  - servicelb
  - traefik
service k3s start

FAQ

stable 版本​

curl -sf https://update.k3s.io/v1-release/channels | jq -r '.data[] | select(.id == "stable") | .latest'
curl -sf https://update.k3s.io/v1-release/channels | yq -r '.data[] | select(.id == "stable") | .latest'

cluster-init​

默认为 SQLite，加 cluster-init: true 重启后会使用 etcd

本地 registry 缓存​

cat << YAML > /etc/rancher/k3s/registries.yaml
mirrors:
  docker.io:
    endpoint:
      - http://docker-registry:5000
      - https://fogjl973.mirror.aliyuncs.com
      - https://8x40wsit.mirror.aliyuncs.com
      - https://docker.mirrors.ustc.edu.cn
      - https://registry-1.docker.io
configs:
  "docker-registry:5000":
YAML
# 配置了 REMOTEURL 可用于做 DockerHub 缓存，但是不能 PUSH https://github.com/distribution/distribution/issues/2386
# 不配置 REMOTEURL 可用于 AirGap 本地 Push，也能部署两个，推一个缓存一个
docker run --rm -it \
  -p 5000:5000 \
  -e REGISTRY_PROXY_REMOTEURL=https://registry-1.docker.io \
  -v $PWD/data:/var/lib/registry \
  --name registry registry:2

# 能直接使用 docker-registry 而不是用 IP
echo "127.0.0.1 docker-registry" >> /etc/hosts

zfs k3s zvol​

# -s sparse volume 不保留空间
zfs create -s -V 200GB data/k3s-vol
mkfs.ext4 /dev/zvol/data/k3s-vol

# 可以放在其他位置然后修改 data-dir
# mkdir -p /data/k3s
# mount /dev/zvol/data/k3s-vol /data/k3s

mkdir -p /var/lib/racher/k3s
mount /dev/zvol/data/k3s-vol /var/lib/racher/k3s
echo "/dev/zvol/data/k3s-vol /var/lib/racher/k3s ext4 rw,relatime,stripe=4 0 0" | tee -a /etc/fstab

zfs rest storage​

# System
zfs create data/var
zfs create -o mountpoint=/var/log/ data/var/log
zfs create -o mountpoint=/var/lib/kubelet data/var/kubelet

# Docker
zfs create -s -V 200GB data/docker-vol
mkfs.ext4 /dev/zvol/data/docker-vol

mkdir -p /var/lib/docker/
mount /dev/zvol/data/docker-vol /var/lib/docker/
echo "/dev/zvol/data/docker-vol /var/lib/docker ext4 rw,relatime,stripe=4 0 0" | tee -a /etc/fstab

zfs snapshotter​

caution
  • 不推荐使用
    • vol 多了 zfs list 很慢
  • 使用 zvol
  • zfs 2.2 支持 overlayfs - 之后可以迁移出来
zfs create -o mountpoint=/var/lib/racher/k3s/containerd/io.containerd.snapshotter.v1.zfs data/k3s-snapshotter
echo "snapshotter: zfs" >> /etc/rancher/k3s/config.yaml
# 非 root 出现
k3s check-config
# 此时不会出现
sudo k3s check-config

# /usr/local/bin/k3s check-config
# PATH=/data/var/k3s/data/current/bin/:$PATH

AlpineLinux openrc sourcex​

sed 's/sourcex/\./g' -i /etc/init.d/k3s