kubeadm是Kubernetes官方提供的用于快速安部署Kubernetes集群的工具,伴随Kubernetes每个版本的发布都会同步更新,kubeadm会对集群配置方面的一些实践做调整,通过实验kubeadm可以学习到Kubernetes官方在集群配置上一些新的最佳实践。
1.准备
1.1 系统配置
在安装之前,需要先做好如下准备。3台CentOS 7.9主机如下:
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cat /etc/hosts
192.168.96.151 node1
192.168.96.152 node2
192.168.96.153 node3
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在各个主机上完成下面的系统配置。
如果各个主机启用了防火墙策略,需要开放Kubernetes各个组件所需要的端口,可以查看Ports and Protocols中的内容, 开放相关端口或者关闭主机的防火墙。
禁用SELINUX:
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vi /etc/selinux/config
SELINUX=disabled
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创建/etc/modules-load.d/containerd.conf配置文件:
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cat << EOF > /etc/modules-load.d/containerd.conf
overlay
br_netfilter
EOF
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执行以下命令使配置生效:
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modprobe overlay
modprobe br_netfilter
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创建/etc/sysctl.d/99-kubernetes-cri.conf配置文件:
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cat << EOF > /etc/sysctl.d/99-kubernetes-cri.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
user.max_user_namespaces=28633
EOF
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执行以下命令使配置生效:
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sysctl -p /etc/sysctl.d/99-kubernetes-cri.conf
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1.2 配置服务器支持开启ipvs的前提条件
由于ipvs已经加入到了内核的主干,所以为kube-proxy开启ipvs的前提需要加载以下的内核模块:
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ip_vs
ip_vs_rr
ip_vs_wrr
ip_vs_sh
nf_conntrack_ipv4
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在各个服务器节点上执行以下脚本:
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cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF
chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep -e ip_vs -e nf_conntrack_ipv4
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上面脚本创建了的/etc/sysconfig/modules/ipvs.modules
文件,保证在节点重启后能自动加载所需模块。 使用lsmod | grep -e ip_vs -e nf_conntrack_ipv4
命令查看是否已经正确加载所需的内核模块。
接下来还需要确保各个节点上已经安装了ipset软件包,为了便于查看ipvs的代理规则,最好安装一下管理工具ipvsadm。
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yum install -y ipset ipvsadm
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如果不满足以上前提条件,则即使kube-proxy的配置开启了ipvs模式,也会退回到iptables模式。
1.3 部署容器运行时Containerd
在各个服务器节点上安装容器运行时Containerd。
下载Containerd的二进制包:
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wget https://github.com/containerd/containerd/releases/download/v1.6.14/cri-containerd-cni-1.6.14-linux-amd64.tar.gz
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cri-containerd-cni-1.6.14-linux-amd64.tar.gz
压缩包中已经按照官方二进制部署推荐的目录结构布局好。
里面包含了systemd配置文件,containerd以及cni的部署文件。
将解压缩到系统的根目录/
中:
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tar -zxvf cri-containerd-cni-1.6.14-linux-amd64.tar.gz -C /
etc/
etc/cni/
etc/cni/net.d/
etc/cni/net.d/10-containerd-net.conflist
etc/systemd/
etc/systemd/system/
etc/systemd/system/containerd.service
etc/crictl.yaml
usr/
usr/local/
usr/local/sbin/
usr/local/sbin/runc
usr/local/bin/
usr/local/bin/containerd-stress
usr/local/bin/containerd-shim
usr/local/bin/containerd-shim-runc-v1
usr/local/bin/crictl
usr/local/bin/critest
usr/local/bin/containerd-shim-runc-v2
usr/local/bin/ctd-decoder
usr/local/bin/containerd
usr/local/bin/ctr
opt/
opt/cni/
opt/cni/bin/
opt/cni/bin/ptp
opt/cni/bin/bandwidth
opt/cni/bin/static
opt/cni/bin/dhcp
...
opt/containerd/
opt/containerd/cluster/
...
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注意经测试cri-containerd-cni-1.6.4-linux-amd64.tar.gz包中包含的runc在CentOS 7下的动态链接有问题,这里从runc的github上单独下载runc,并替换上面安装的containerd中的runc:
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wget https://github.com/opencontainers/runc/releases/download/v1.1.2/runc.amd64
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接下来生成containerd的配置文件:
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mkdir -p /etc/containerd
containerd config default > /etc/containerd/config.toml
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根据文档Container runtimes
中的内容,对于使用systemd作为init system的Linux的发行版,使用systemd作为容器的cgroup driver可以确保服务器节点在资源紧张的情况更加稳定,因此这里配置各个节点上containerd的cgroup driver为systemd。
修改前面生成的配置文件/etc/containerd/config.toml
:
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[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
...
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options]
SystemdCgroup = true
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再修改/etc/containerd/config.toml
中的
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[plugins."io.containerd.grpc.v1.cri"]
...
# sandbox_image = "k8s.gcr.io/pause:3.6"
sandbox_image = "registry.aliyuncs.com/google_containers/pause:3.9"
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配置containerd开机启动,并启动containerd
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systemctl enable containerd --now
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使用crictl测试一下,确保可以打印出版本信息并且没有错误信息输出:
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crictl version
Version: 0.1.0
RuntimeName: containerd
RuntimeVersion: v1.6.14
RuntimeApiVersion: v1
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2.使用kubeadm部署Kubernetes
2.1 安装kubeadm和kubelet
下面在各节点安装kubeadm和kubelet:
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cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=0
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
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yum makecache fast
yum install kubelet kubeadm kubectl
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运行kubelet --help
可以看到原来kubelet的绝大多数命令行flag参数都被DEPRECATED
了,官方推荐我们使用--config
指定配置文件,并在配置文件中指定原来这些flag所配置的内容。具体内容可以查看这里Set Kubelet parameters via a config file。最初Kubernetes这么做是为了支持动态Kubelet配置(Dynamic Kubelet Configuration),但动态Kubelet配置特性从k8s 1.22中已弃用,并在1.24中被移除。如果需要调整集群汇总所有节点kubelet的配置,还是推荐使用ansible等工具将配置分发到各个节点。
kubelet的配置文件必须是json或yaml格式,具体可查看这里。
Kubernetes 1.8开始要求关闭系统的Swap,如果不关闭,默认配置下kubelet将无法启动。
关闭系统的Swap方法如下:
修改/etc/fstab
文件,注释掉 SWAP 的自动挂载,使用free -m
确认swap已经关闭。
swappiness参数调整,修改/etc/sysctl.d/99-kubernetes-cri.conf
添加下面一行:
执行sysctl -p /etc/sysctl.d/99-kubernetes-cri.conf
使修改生效。
2.2 使用kubeadm init初始化集群
在各节点开机启动kubelet服务:
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systemctl enable kubelet.service
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使用kubeadm config print init-defaults --component-configs KubeletConfiguration
可以打印集群初始化默认的使用的配置:
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apiVersion: kubeadm.k8s.io/v1beta3
bootstrapTokens:
- groups:
- system:bootstrappers:kubeadm:default-node-token
token: abcdef.0123456789abcdef
ttl: 24h0m0s
usages:
- signing
- authentication
kind: InitConfiguration
localAPIEndpoint:
advertiseAddress: 1.2.3.4
bindPort: 6443
nodeRegistration:
criSocket: unix:///var/run/containerd/containerd.sock
imagePullPolicy: IfNotPresent
name: node
taints: null
---
apiServer:
timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta3
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controllerManager: {}
dns: {}
etcd:
local:
dataDir: /var/lib/etcd
imageRepository: registry.k8s.io
kind: ClusterConfiguration
kubernetesVersion: 1.26.0
networking:
dnsDomain: cluster.local
serviceSubnet: 10.96.0.0/12
scheduler: {}
---
apiVersion: kubelet.config.k8s.io/v1beta1
authentication:
anonymous:
enabled: false
webhook:
cacheTTL: 0s
enabled: true
x509:
clientCAFile: /etc/kubernetes/pki/ca.crt
authorization:
mode: Webhook
webhook:
cacheAuthorizedTTL: 0s
cacheUnauthorizedTTL: 0s
cgroupDriver: systemd
clusterDNS:
- 10.96.0.10
clusterDomain: cluster.local
cpuManagerReconcilePeriod: 0s
evictionPressureTransitionPeriod: 0s
fileCheckFrequency: 0s
healthzBindAddress: 127.0.0.1
healthzPort: 10248
httpCheckFrequency: 0s
imageMinimumGCAge: 0s
kind: KubeletConfiguration
logging:
flushFrequency: 0
options:
json:
infoBufferSize: "0"
verbosity: 0
memorySwap: {}
nodeStatusReportFrequency: 0s
nodeStatusUpdateFrequency: 0s
rotateCertificates: true
runtimeRequestTimeout: 0s
shutdownGracePeriod: 0s
shutdownGracePeriodCriticalPods: 0s
staticPodPath: /etc/kubernetes/manifests
streamingConnectionIdleTimeout: 0s
syncFrequency: 0s
volumeStatsAggPeriod: 0s
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从默认的配置中可以看到,可以使用imageRepository
定制在集群初始化时拉取k8s所需镜像的地址。基于默认配置定制出本次使用kubeadm初始化集群所需的配置文件kubeadm.yaml:
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apiVersion: kubeadm.k8s.io/v1beta3
kind: InitConfiguration
localAPIEndpoint:
advertiseAddress: 192.168.96.151
bindPort: 6443
nodeRegistration:
criSocket: unix:///run/containerd/containerd.sock
taints:
- effect: PreferNoSchedule
key: node-role.kubernetes.io/master
---
apiVersion: kubeadm.k8s.io/v1beta2
kind: ClusterConfiguration
kubernetesVersion: 1.26.0
imageRepository: registry.aliyuncs.com/google_containers
networking:
podSubnet: 10.244.0.0/16
---
apiVersion: kubelet.config.k8s.io/v1beta1
kind: KubeletConfiguration
cgroupDriver: systemd
failSwapOn: false
---
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
mode: ipvs
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这里定制了imageRepository
为阿里云的registry,避免因gcr被墙,无法直接拉取镜像。criSocket
设置了容器运行时为containerd。
同时设置kubelet的cgroupDriver
为systemd,设置kube-proxy代理模式为ipvs
。
在开始初始化集群之前可以使用kubeadm config images pull --config kubeadm.yaml
预先在各个服务器节点上拉取所k8s需要的容器镜像。
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kubeadm config images pull --config kubeadm.yaml
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-apiserver:v1.26.0
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-controller-manager:v1.26.0
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-scheduler:v1.26.0
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-proxy:v1.26.0
[config/images] Pulled registry.aliyuncs.com/google_containers/pause:3.9
[config/images] Pulled registry.aliyuncs.com/google_containers/etcd:3.5.6-0
[config/images] Pulled registry.aliyuncs.com/google_containers/coredns:v1.9.3
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接下来使用kubeadm初始化集群,选择node1作为Master Node,在node1上执行下面的命令:
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kubeadm init --config kubeadm.yaml
W0104 16:55:08.531622 29428 common.go:84] your configuration file uses a deprecated API spec: "kubeadm.k8s.io/v1beta2". Please use 'kubeadm config migrate --old-config old.yaml --new-config new.yaml', which will write the new, similar spec using a newer API version.
[init] Using Kubernetes version: v1.26.0
[preflight] Running pre-flight checks
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Using existing ca certificate authority
[certs] Using existing apiserver certificate and key on disk
[certs] Using existing apiserver-kubelet-client certificate and key on disk
[certs] Using existing front-proxy-ca certificate authority
[certs] Using existing front-proxy-client certificate and key on disk
[certs] Using existing etcd/ca certificate authority
[certs] Using existing etcd/server certificate and key on disk
[certs] Using existing etcd/peer certificate and key on disk
[certs] Using existing etcd/healthcheck-client certificate and key on disk
[certs] Using existing apiserver-etcd-client certificate and key on disk
[certs] Using the existing "sa" key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Using existing kubeconfig file: "/etc/kubernetes/admin.conf"
[kubeconfig] Using existing kubeconfig file: "/etc/kubernetes/kubelet.conf"
[kubeconfig] Using existing kubeconfig file: "/etc/kubernetes/controller-manager.conf"
[kubeconfig] Using existing kubeconfig file: "/etc/kubernetes/scheduler.conf"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Starting the kubelet
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 9.503362 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node node1 as control-plane by adding the labels: [node-role.kubernetes.io/control-plane node.kubernetes.io/exclude-from-external-load-balancers]
[mark-control-plane] Marking the node node1 as control-plane by adding the taints [node-role.kubernetes.io/master:PreferNoSchedule]
[bootstrap-token] Using token: o4pn35.3zjs1udp6uw1eg8w
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] Configured RBAC rules to allow Node Bootstrap tokens to get nodes
[bootstrap-token] Configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] Configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] Configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
Alternatively, if you are the root user, you can run:
export KUBECONFIG=/etc/kubernetes/admin.conf
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 192.168.96.151:6443 --token o4pn35.3zjs1udp6uw1eg8w \
--discovery-token-ca-cert-hash sha256:9db5dbc8e0c6d8f399fad5afbac4a169a6a253eae23d24cb3edbd8d7ac0877a9
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上面记录了完成的初始化输出的内容,根据输出的内容基本上可以看出手动初始化安装一个Kubernetes集群所需要的关键步骤。
其中有以下关键内容:
[certs]
生成相关的各种证书
[kubeconfig]
生成相关的kubeconfig文件
[kubelet-start]
生成kubelet的配置文件"/var/lib/kubelet/config.yaml"
[control-plane]
使用/etc/kubernetes/manifests
目录中的yaml文件创建apiserver、controller-manager、scheduler的静态pod
[bootstraptoken]
生成token记录下来,后边使用kubeadm join
往集群中添加节点时会用到
[addons]
安装基本插件:CoreDNS
, kube-proxy
- 下面的命令是配置常规用户如何使用kubectl访问集群:
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mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
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- 最后给出了将另外2个节点加入集群的命令:
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kubeadm join 192.168.96.151:6443 --token o4pn35.3zjs1udp6uw1eg8w \
--discovery-token-ca-cert-hash sha256:9db5dbc8e0c6d8f399fad5afbac4a169a6a253eae23d24cb3edbd8d7ac0877a9
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查看一下集群状态,确认个组件都处于healthy状态,结果出现了错误:
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kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
controller-manager Healthy ok
scheduler Healthy ok
etcd-0 Healthy {"health":"true","reason":""}
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集群初始化如果遇到问题,可以使用kubeadm reset
命令进行清理。
2.3 安装包管理器helm 3
Helm是Kubernetes的包管理器,后续流程也将使用Helm安装Kubernetes的常用组件。
这里先在master节点node1上安装helm。
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wget https://get.helm.sh/helm-v3.10.3-linux-amd64.tar.gz
tar -zxvf helm-v3.10.3-linux-amd64.tar.gz
mv linux-amd64/helm /usr/local/bin/
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执行helm list
确认没有错误输出。
2.4 部署Pod Network组件Calico
选择calico作为k8s的Pod网络组件,下面使用helm在k8s集群中安装calico。
下载tigera-operator
的helm chart:
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wget https://github.com/projectcalico/calico/releases/download/v3.24.5/tigera-operator-v3.24.5.tgz
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查看这个chart的中可定制的配置:
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helm show values tigera-operator-v3.24.5.tgz
imagePullSecrets: {}
installation:
enabled: true
kubernetesProvider: ""
apiServer:
enabled: true
certs:
node:
key:
cert:
commonName:
typha:
key:
cert:
commonName:
caBundle:
# Resource requests and limits for the tigera/operator pod.
resources: {}
# Tolerations for the tigera/operator pod.
tolerations:
- effect: NoExecute
operator: Exists
- effect: NoSchedule
operator: Exists
# NodeSelector for the tigera/operator pod.
nodeSelector:
kubernetes.io/os: linux
# Custom annotations for the tigera/operator pod.
podAnnotations: {}
# Custom labels for the tigera/operator pod.
podLabels: {}
# Image and registry configuration for the tigera/operator pod.
tigeraOperator:
image: tigera/operator
version: v1.28.5
registry: quay.io
calicoctl:
image: docker.io/calico/ctl
tag: v3.24.5
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定制的values.yaml
如下:
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# 可针对上面的配置进行定制,例如calico的镜像改成从私有库拉取。
# 这里只是个人本地环境测试k8s新版本,这里只有下面几行配置
apiServer:
enabled: false
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使用helm安装calico:
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helm install calico tigera-operator-v3.24.5.tgz -n kube-system --create-namespace -f values.yaml
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等待并确认所有pod处于Running状态:
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kubectl get pod -n kube-system | grep tigera-operator
tigera-operator-5fb55776df-wxbph 1/1 Running 0 5m10s
kubectl get pods -n calico-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-68884f975d-5d7p9 1/1 Running 0 5m24s
calico-node-twbdh 1/1 Running 0 5m24s
calico-typha-7b4bdd99c5-ssdn2 1/1 Running 0 5m24s
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查看一下calico向k8s中添加的api资源:
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kubectl api-resources | grep calico
bgpconfigurations crd.projectcalico.org/v1 false BGPConfiguration
bgppeers crd.projectcalico.org/v1 false BGPPeer
blockaffinities crd.projectcalico.org/v1 false BlockAffinity
caliconodestatuses crd.projectcalico.org/v1 false CalicoNodeStatus
clusterinformations crd.projectcalico.org/v1 false ClusterInformation
felixconfigurations crd.projectcalico.org/v1 false FelixConfiguration
globalnetworkpolicies crd.projectcalico.org/v1 false GlobalNetworkPolicy
globalnetworksets crd.projectcalico.org/v1 false GlobalNetworkSet
hostendpoints crd.projectcalico.org/v1 false HostEndpoint
ipamblocks crd.projectcalico.org/v1 false IPAMBlock
ipamconfigs crd.projectcalico.org/v1 false IPAMConfig
ipamhandles crd.projectcalico.org/v1 false IPAMHandle
ippools crd.projectcalico.org/v1 false IPPool
ipreservations crd.projectcalico.org/v1 false IPReservation
kubecontrollersconfigurations crd.projectcalico.org/v1 false KubeControllersConfiguration
networkpolicies crd.projectcalico.org/v1 true NetworkPolicy
networksets crd.projectcalico.org/v1 true NetworkSet
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这些api资源是属于calico的,因此不建议使用kubectl来管理,推荐按照calicoctl来管理这些api资源。
将calicoctl安装为kubectl的插件:
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cd /usr/local/bin
curl -o kubectl-calico -O -L "https://github.com/projectcalico/calicoctl/releases/download/v3.21.5/calicoctl-linux-amd64"
chmod +x kubectl-calico
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验证插件正常工作:
2.5 验证k8s DNS是否可用
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kubectl run curl --image=radial/busyboxplus:curl -it
If you don't see a command prompt, try pressing enter.
[ [email protected]:/ ]$
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进入后执行nslookup kubernetes.default
确认解析正常:
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nslookup kubernetes.default
Server: 10.96.0.10
Address 1: 10.96.0.10 kube-dns.kube-system.svc.cluster.local
Name: kubernetes.default
Address 1: 10.96.0.1 kubernetes.default.svc.cluster.local
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2.6 向Kubernetes集群中添加Node节点
下面将node2, node3添加到Kubernetes集群中,分别在node2, node3上执行:
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kubeadm join 192.168.96.151:6443 --token o4pn35.3zjs1udp6uw1eg8w \
--discovery-token-ca-cert-hash sha256:9db5dbc8e0c6d8f399fad5afbac4a169a6a253eae23d24cb3edbd8d7ac0877a9
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node2和node3加入集群很是顺利,在master节点上执行命令查看集群中的节点:
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kubectl get node
NAME STATUS ROLES AGE VERSION
node1 Ready control-plane 29m v1.26.0
node2 Ready <none> 31s v1.26.0
node3 Ready <none> 19s v1.26.0
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3.Kubernetes常用组件部署
3.1 使用Helm部署ingress-nginx
为了便于将集群中的服务暴露到集群外部,需要使用Ingress。接下来使用Helm将ingress-nginx部署到Kubernetes上。
Nginx Ingress Controller被部署在Kubernetes的边缘节点上。
这里将node1(192.168.96.151)作为边缘节点,打上Label:
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kubectl label node node1 node-role.kubernetes.io/edge=
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下载ingress-nginx的helm chart:
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wget https://github.com/kubernetes/ingress-nginx/releases/download/helm-chart-4.4.2/ingress-nginx-4.4.2.tgz
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查看ingress-nginx-4.4.2.tgz
这个chart的可定制配置:
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helm show values ingress-nginx-4.4.2.tgz
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对values.yaml配置定制如下:
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controller:
ingressClassResource:
name: nginx
enabled: true
default: true
controllerValue: "k8s.io/ingress-nginx"
admissionWebhooks:
enabled: false
replicaCount: 1
image:
# registry: registry.k8s.io
# image: ingress-nginx/controller
# tag: "v1.5.1"
registry: docker.io
image: unreachableg/registry.k8s.io_ingress-nginx_controller
tag: "v1.5.1"
digest: sha256:97fa1ff828554ff4ee1b0416e54ae2238b27d1faa6d314d5a94a92f1f99cf767
hostNetwork: true
nodeSelector:
node-role.kubernetes.io/edge: ''
affinity:
podAntiAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchExpressions:
- key: app
operator: In
values:
- nginx-ingress
- key: component
operator: In
values:
- controller
topologyKey: kubernetes.io/hostname
tolerations:
- key: node-role.kubernetes.io/master
operator: Exists
effect: NoSchedule
- key: node-role.kubernetes.io/master
operator: Exists
effect: PreferNoSchedule
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nginx ingress controller的副本数replicaCount为1,将被调度到node1这个边缘节点上。这里并没有指定nginx ingress controller service的externalIPs,而是通过hostNetwork: true
设置nginx ingress controller使用宿主机网络。
因为k8s.gcr.io被墙,这里替换成unreachableg/registry.k8s.io_ingress-nginx_controller提前拉取一下镜像:
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crictl pull unreachableg/registry.k8s.io_ingress-nginx_controller:v1.5.1
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helm install ingress-nginx ingress-nginx-4.4.2.tgz --create-namespace -n ingress-nginx -f values.yaml
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kubectl get pod -n ingress-nginx
NAME READY STATUS RESTARTS AGE
ingress-nginx-controller-7c96f857f-cbmhx 1/1 Running 0 39s
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测试访问http://192.168.96.151
返回默认的nginx 404页,则部署完成。
3.2 使用Helm部署dashboard
先部署metrics-server:
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wget https://github.com/kubernetes-sigs/metrics-server/releases/download/metrics-server-helm-chart-3.8.3/components.yaml
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修改components.yaml中的image为docker.io/unreachableg/k8s.gcr.io_metrics-server_metrics-server:v0.6.2
。
修改components.yaml中容器的启动参数,加入--kubelet-insecure-tls
。
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kubectl apply -f components.yaml
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metrics-server的pod正常启动后,等一段时间就可以使用kubectl top
查看集群和pod的metrics信息:
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kubectl top node
NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
node1 509m 12% 3654Mi 47%
node2 133m 3% 1786Mi 23%
node3 117m 2% 1810Mi 23%
kubectl top pod -n kube-system
NAME CPU(cores) MEMORY(bytes)
coredns-74586cf9b6-575nl 6m 16Mi
coredns-74586cf9b6-mbn8s 5m 17Mi
etcd-node1 49m 91Mi
kube-apiserver-node1 142m 490Mi
kube-controller-manager-node1 38m 54Mi
kube-proxy-k5lzs 26m 19Mi
kube-proxy-rb5pf 9m 15Mi
kube-proxy-w5zpk 27m 16Mi
kube-scheduler-node1 7m 18Mi
metrics-server-8dfd488f5-r8pbh 8m 21Mi
tigera-operator-5fb55776df-wxbph 10m 38Mi
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接下来使用helm部署k8s的dashboard,添加chart repo:
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helm repo add kubernetes-dashboard https://kubernetes.github.io/dashboard/
helm repo update
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查看chart的可定制配置:
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helm show values kubernetes-dashboard/kubernetes-dashboard
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对values.yaml定制配置如下:
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image:
repository: kubernetesui/dashboard
tag: v2.7.0
ingress:
enabled: true
annotations:
nginx.ingress.kubernetes.io/ssl-redirect: "true"
nginx.ingress.kubernetes.io/backend-protocol: "HTTPS"
hosts:
- k8s.example.com
tls:
- secretName: example-com-tls-secret
hosts:
- k8s.example.com
metricsScraper:
enabled: true
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以上配置中, 部署的dashboard将通过ingress以域名k8s.example.com
暴露出来, 并为此域名开启HTTPS。
为了开启HTTPS,需要为此域名申请SSL证书或使用自签证书,这里使用的证书和私钥文件分别为cert.pem
和key.pem
。
先创建存放k8s.example.com
ssl证书的secret:
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kubectl create secret tls example-com-tls-secret \
--cert=cert.pem \
--key=key.pem \
-n kube-system
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使用helm部署dashboard:
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helm install kubernetes-dashboard kubernetes-dashboard/kubernetes-dashboard \
-n kube-system \
-f values.yaml
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确认上面的命令部署成功。
创建管理员sa:
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kubectl create serviceaccount kube-dashboard-admin-sa -n kube-system
kubectl create clusterrolebinding kube-dashboard-admin-sa \
--clusterrole=cluster-admin --serviceaccount=kube-system:kube-dashboard-admin-sa
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创建集群管理员登录dashboard所需token:
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kubectl create token kube-dashboard-admin-sa -n kube-system --duration=87600h
eyJhbGciOiJSUzI1NiIsImtpZCI6IlU1SlpSTS1YekNuVzE0T1k5TUdTOFFqN25URWxKckt6OUJBT0xzblBsTncifQ.eyJhdWQiOlsiaHR0cHM6Ly9rdWJlcm5ldGVzLmRlZmF1bHQuc3ZjLmNsdXN0ZXIubG9jYWwiXSwiZXhwIjoxOTY4OTA4MjgyLCJpYXQiOjE2NTM1NDgyODIsImlzcyI6Imh0dHBzOi8va3ViZXJuZXRlcy5kZWZhdWx0LnN2Yy5jbHVzdGVyLmxvY2FsIiwia3ViZXJuZXRlcy5pbyI6eyJuYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsInNlcnZpY2VhY2NvdW50Ijp7Im5hbWUiOiJrdWJlLWRhc2hib2FyZC1hZG1pbi1zYSIsInVpZCI6IjY0MmMwMmExLWY1YzktNDFjNy04Mjc5LWQ1ZmI3MGRjYTQ3ZSJ9fSwibmJmIjoxNjUzNTQ4MjgyLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6a3ViZS1zeXN0ZW06a3ViZS1kYXNoYm9hcmQtYWRtaW4tc2EifQ.Xqxlo2vJ9Hb6UUVIqwvc8I5bahdxKzSRSaQI_67Yt7_YEHmkkHApxUGlwJYTKF9ufww3btlCmM8PtRn5_Q1yv-HAFyTOYKo8WHZ9UCm1bT3X8V8g4GQwZIl2dwmlUmKb1unBz2-em2uThQ015bMPDE8a42DV_bOwWjljVXat0nwV14nGorC8vKLjXbohrIJ3G1pgCJvlBn99F1RelmSUSQLlolUFoxpN6MamYTElwR6FfD-AGmFXvZSbcFaqVW0oxJHV70Gjs2igOtpqHFxxPlHT8aQzlRiybPtFyBf9Ll87TmVJimT89z8wv2si2Nee8bB2jhsApLn8TJyUSlbTXA
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使用上面的token登录k8s dashboard。

参考