K8S 二进制安装
K8S 二进制安装1. 环境准备1.1 安装规划1.2 系统设置2. 安装 docker3. TLS 证书3.1 证书工具3.2 证书归类3.3 CA 证书3.4 etcd 证书3.5 kube-apiserver 证书3.6 kube-controller-manager 证书3.8 kube-scheduler 证书3.9 admin 证书3.10 kube-proxy 证书3.11 证书信息
K8S 二进制安装
1. 环境准备
1.1 安装规划
角色 | IP | 组件 |
---|---|---|
k8s-master1 | 192.168.80.45 | etcd, api-server, controller-manager, scheduler, docker |
k8s-node01 | 192.168.80.46 | etcd, kubelet, kube-proxy, docker |
k8s-node02 | 192.168.80.47 | etcd, kubelet, kube-proxy, docker |
软件版本:
软件 | 版本 | 备注 |
---|---|---|
OS | Ubuntu 16.04.6 LTS | |
Kubernetes | 1.19.11 | |
Etcd | v3.4.15 | |
Docker | 19.03.9 |
1.2 系统设置
# 1. 修改主机名
hostnamectl set-hostname k8s-master1
hostnamectl set-hostname k8s-node01
hostnamectl set-hostname k8s-node02
# 2. 主机名解析
cat >> /etc/hosts <<EOF
192.168.80.45 k8s-master1
192.168.80.46 k8s-node01
192.168.80.47 k8s-node02
EOF
# 3. 禁用 swap
swapoff -a && sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab
# 4. 将桥接的IPv4流量传递到iptables的链
cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system
# 5. 域名解析
echo "nameserver 8.8.8.8" >> /etc/resolv.conf
# 6. 时间同步
apt install ntpdate -y
ntpdate ntp1.aliyun.com
crontab -e
*/30 * * * * /usr/sbin/ntpdate-u ntp1.aliyun.com >> /var/log/ntpdate.log 2>&1
# 7. 日志目录
mkdir -p /var/log/kubernetes
2. 安装 docker
mkdir -p $HOME/k8s-install && cd $HOME/k8s-install
# 1. 下载安装包
wget https://download.docker.com/linux/static/stable/x86_64/docker-19.03.9.tgz
tar zxvf docker-19.03.9.tgz
mv docker/* /usr/bin
docker version
# 2. 开机启动配置
cat > /lib/systemd/system/docker.service << EOF
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target
[Service]
Type=notify
ExecStart=/usr/bin/dockerd
ExecReload=/bin/kill -s HUP $MAINPID
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
TimeoutStartSec=0
Delegate=yes
KillMode=process
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s
[Install]
WantedBy=multi-user.target
EOF
# 3. 启动
systemctl daemon-reload
systemctl start docker
systemctl status docker
systemctl enable docker
3. TLS 证书
3.1 证书工具
mkdir -p $HOME/k8s-install && cd $HOME/k8s-install
wget https://github.com/cloudflare/cfssl/releases/download/v1.5.0/cfssl_1.5.0_linux_amd64
wget https://github.com/cloudflare/cfssl/releases/download/v1.5.0/cfssljson_1.5.0_linux_amd64
wget https://github.com/cloudflare/cfssl/releases/download/v1.5.0/cfssl-certinfo_1.5.0_linux_amd64
mv cfssl_1.5.0_linux_amd64 /usr/local/bin/cfssl
mv cfssljson_1.5.0_linux_amd64 /usr/local/bin/cfssljson
mv cfssl-certinfo_1.5.0_linux_amd64 /usr/bin/cfssl-certinfo
chmod /usr/local/bin/cfssl*
3.2 证书归类
生成的 CA 证书和秘钥文件如下:
组件 | 证书 | 密钥 | 备注 |
---|---|---|---|
etcd | ca.pem、etcd.pem | etcd-key.pem | |
apiserver | ca.pem、apiserver.pem | apiserver-key.pem | |
controller-manager | ca.pem、kube-controller-manager.pem | ca-key.pem、kube-controller-manager-key.pem | kubeconfig |
scheduler | ca.pem、kube-scheduler.pem | kube-scheduler-key.pem | kubeconfig |
kubelet | ca.pem | kubeconfig+token | |
kube-proxy | ca.pem、kube-proxy.pem | kube-proxy-key.pem | kubeconfig |
kubectl | ca.pem、admin.pem | admin-key.pem |
3.3 CA 证书
CA: Certificate Authority
mkdir -p /root/ssl && cd /root/ssl
# 1. CA 配置文件
cat > ca-config.json <<EOF
{
"signing": {
"default": {
"expiry": "87600h"
},
"profiles": {
"kubernetes": {
"usages": [
"signing",
"key encipherment",
"server auth",
"client auth"
],
"expiry": "87600h"
}
}
}
}
EOF
# 2. CA 证书签名请求文件
cat > ca-csr.json <<EOF
{
"CN": "kubernetes",
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "k8s",
"OU": "System"
}
],
"ca": {
"expiry": "87600h"
}
}
EOF
# 3. 生成CA证书和密钥
cfssl gencert -initca ca-csr.json | cfssljson -bare ca
ls ca*
ca-config.json ca.csr ca-csr.json ca-key.pem ca.pem
3.4 etcd 证书
注意:hosts 中的IP地址,分别指定了 etcd
集群的主机 IP
# 1. 证书签名请求文件
cat > etcd-csr.json <<EOF
{
"CN": "etcd",
"hosts": [
"127.0.0.1",
"localhost",
"192.168.80.45",
"192.168.80.46",
"192.168.80.47"
],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "etcd",
"OU": "System"
}
]
}
EOF
# 2. 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes etcd-csr.json | cfssljson -bare etcd
3.5 kube-apiserver 证书
注意:hosts 中的IP地址,分别指定了 kubernetes master
集群的主机 IP 和 kubernetes
服务的服务 IP(一般是 kube-apiserver
指定的 service-cluster-ip-range
网段的第一个IP,如 10.254.0.1)
# 1. 证书签名请求文件
cat > apiserver-csr.json <<EOF
{
"CN": "kubernetes",
"hosts": [
"127.0.0.1",
"localhost",
"192.168.80.1",
"192.168.80.2",
"192.168.80.45",
"192.168.80.46",
"192.168.80.47",
"10.254.0.1",
"kubernetes",
"kubernetes.default",
"kubernetes.default.svc",
"kubernetes.default.svc.cluster",
"kubernetes.default.svc.cluster.local"
],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "k8s",
"OU": "System"
}
]
}
EOF
# 2. 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes apiserver-csr.json | cfssljson -bare apiserver
3.6 kube-controller-manager 证书
# 1. 证书签名请求文件
cat > kube-controller-manager-csr.json <<EOF
{
"CN": "system:kube-controller-manager",
"hosts": [],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "system:masters",
"OU": "System"
}
]
}
EOF
# 2. 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-controller-manager-csr.json | cfssljson -bare kube-controller-manager
3.8 kube-scheduler 证书
# 1. 证书签名请求文件
cat > kube-scheduler-csr.json << EOF
{
"CN": "system:kube-scheduler",
"hosts": [],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "system:masters",
"OU": "System"
}
]
}
EOF
# 2. 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-scheduler-csr.json | cfssljson -bare kube-scheduler
3.9 admin 证书
- 后续
kube-apiserver
使用RBAC
对客户端(如kubelet
、kube-proxy
、Pod
)请求进行授权; kube-apiserver
预定义了一些RBAC
使用的RoleBindings
,如cluster-admin
将 Groupsystem:masters
与 Rolecluster-admin
绑定,该 Role 授予了调用kube-apiserver
的所有 API的权限;- O 指定该证书的 Group 为
system:masters
,kubelet
使用该证书访问kube-apiserver
时 ,由于证书被 CA 签名,所以认证通过,同时由于证书用户组为经过预授权的system:masters
,所以被授予访问所有 API 的权限;
# 1. 证书签名请求文件
cat > admin-csr.json <<EOF
{
"CN": "admin",
"hosts": [],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "system:masters",
"OU": "System"
}
]
}
EOF
# 2. 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes admin-csr.json | cfssljson -bare admin
ls admin*
admin.csr admin-csr.json admin-key.pem admin.pem
搭建完 kubernetes 集群后,可以通过命令: kubectl get clusterrolebinding cluster-admin -o yaml
,查看到 clusterrolebinding cluster-admin
的 subjects 的 kind 是 Group,name 是 system:masters
。 roleRef
对象是 ClusterRole cluster-admin
。 即 system:masters Group
的 user 或者 serviceAccount
都拥有 cluster-admin
的角色。 因此在使用 kubectl 命令时候,才拥有整个集群的管理权限。
kubectl get clusterrolebinding cluster-admin -o yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
annotations:
rbac.authorization.kubernetes.io/autoupdate: "true"
creationTimestamp: 2017-04-11T11:20:42Z
labels:
kubernetes.io/bootstrapping: rbac-defaults
name: cluster-admin
resourceVersion: "52"
selfLink: /apis/rbac.authorization.k8s.io/v1/clusterrolebindings/cluster-admin
uid: e61b97b2-1ea8-11e7-8cd7-f4e9d49f8ed0
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- apiGroup: rbac.authorization.k8s.io
kind: Group
name: system:masters
3.10 kube-proxy 证书
- CN 指定该证书的 User 为
system:kube-proxy
; kube-apiserver
预定义的 RoleBindingsystem:node-proxier
将Usersystem:kube-proxy
与 Rolesystem:node-proxier
绑定,该 Role 授予了调用kube-apiserver
Proxy 相关 API 的权限;
# 1. 证书签名请求文件
cat > kube-proxy-csr.json <<EOF
{
"CN": "system:kube-proxy",
"hosts": [],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "k8s",
"OU": "System"
}
]
}
EOF
# 2. 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy
3.11 证书信息
cfssl-certinfo -cert apiserver.pem
{
"subject": {
"common_name": "kubernetes",
"country": "CN",
"organization": "k8s",
"organizational_unit": "System",
"locality": "BeiJing",
"province": "BeiJing",
"names": [
"CN",
"BeiJing",
"BeiJing",
"k8s",
"System",
"kubernetes"
]
},
"issuer": {
"common_name": "kubernetes",
"country": "CN",
"organization": "k8s",
"organizational_unit": "System",
"locality": "BeiJing",
"province": "BeiJing",
"names": [
"CN",
"BeiJing",
"BeiJing",
"k8s",
"System",
"kubernetes"
]
},
"serial_number": "275867496157961939649344217740970264800633176866",
"sans": [
"localhost",
"kubernetes",
"kubernetes.default",
"kubernetes.default.svc",
"kubernetes.default.svc.cluster",
"kubernetes.default.svc.cluster.local",
"127.0.0.1",
"192.168.80.1",
"192.168.80.2",
"192.168.80.45",
"192.168.80.46",
"192.168.80.47",
"10.254.0.1"
],
"not_before": "2021-06-09T05:20:00Z",
"not_after": "2031-06-07T05:20:00Z",
"sigalg": "SHA256WithRSA",
"authority_key_id": "",
"subject_key_id": "E3:84:0F:9C:00:07:4A:8F:5C:B2:35:45:A0:50:4D:3E:9D:C0:B4:D0",
"pem": "-----BEGIN CERTIFICATE-----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\n-----END CERTIFICATE-----\n"
}
3.12 分发证书
所有节点
mkdir -p /etc/kubernetes/pki
cp *.pem /etc/kubernetes/pki
tar cvf pki.tar /etc/kubernetes/pki
scp pki.tar ubuntu@192.168.80.46:/home/ubuntu
scp pki.tar ubuntu@192.168.80.47:/home/ubuntu
sudo -i
cd / && mv /home/ubuntu/pki.tar / && tar xvf pki.tar && rm -f pki.tar
4. 安装 etcd
4.1 节点 etcd-1
mkdir -p $HOME/k8s-install && cd $HOME/k8s-install
# 1. 下载并安装
wget https://github.com/etcd-io/etcd/releases/download/v3.4.15/etcd-v3.4.15-linux-amd64.tar.gz
tar zxvf etcd-v3.4.15-linux-amd64.tar.gz
mv etcd-v3.4.15-linux-amd64/{etcd,etcdctl} /usr/bin/
# 2. 配置文件
mkdir -p /etc/etcd
cat > /etc/etcd/etcd.conf << EOF
#[Member]
ETCD_NAME="etcd-1"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.80.45:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.80.45:2379,https://127.0.0.1:2379"
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.80.45:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.80.45:2379"
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.80.45:2380,etcd-2=https://192.168.80.46:2380,etcd-3=https://192.168.80.47:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF
# 3. 开机启动
cat > /lib/systemd/system/etcd.service << EOF
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target
[Service]
Type=notify
EnvironmentFile=-/etc/etcd/etcd.conf
ExecStart=/usr/bin/etcd \
--cert-file=/etc/kubernetes/pki/etcd.pem \
--key-file=/etc/kubernetes/pki/etcd-key.pem \
--peer-cert-file=/etc/kubernetes/pki/etcd.pem \
--peer-key-file=/etc/kubernetes/pki/etcd-key.pem \
--trusted-ca-file=/etc/kubernetes/pki/ca.pem \
--peer-trusted-ca-file=/etc/kubernetes/pki/ca.pem \
--logger=zap
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF
# 4. 准备克隆文件
tar cvf etcd-clone.tar /usr/bin/etcd* /etc/etcd /lib/systemd/system/etcd.service
scp etcd-clone.tar ubuntu@192.168.80.46:/home/ubuntu
scp etcd-clone.tar ubuntu@192.168.80.47:/home/ubuntu
4.2 其他节点
# 1. 解压克隆文件
sudo -i
cd / && mv /home/ubuntu/etcd-clone.tar / && tar xvf etcd-clone.tar && rm -f etcd-clone.tar
# 2. 修改配置文件
vi /etc/etcd/etcd.conf
#[Member]
ETCD_NAME="etcd-2" # change to local
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.80.46:2380" # change to local
ETCD_LISTEN_CLIENT_URLS="https://192.168.80.46:2379,https://127.0.0.1:2379" # change to local
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.80.46:2380" # change to local
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.80.46:2379" # change to local
ETCD_INITIAL_CLUSTER="etcd-1=https://192.168.80.45:2380,etcd-2=https://192.168.80.46:2380,etcd-3=https://192.168.80.47:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
4.3 启动
# 1. 开机启动
systemctl daemon-reload
systemctl start etcd
systemctl status etcd
systemctl enable etcd
# 2. 运行状态
etcdctl member list --cacert=/etc/kubernetes/pki/ca.pem --cert=/etc/kubernetes/pki/etcd.pem --key=/etc/kubernetes/pki/etcd-key.pem --write-out=table
+------------------+---------+--------+----------------------------+----------------------------+------------+
| ID | STATUS | NAME | PEER ADDRS | CLIENT ADDRS | IS LEARNER |
+------------------+---------+--------+----------------------------+----------------------------+------------+
| 46bc5ad35e418584 | started | etcd-1 | https://192.168.80.45:2380 | https://192.168.80.45:2379 | false |
| 8f347c1327049bc8 | started | etcd-3 | https://192.168.80.47:2380 | https://192.168.80.47:2379 | false |
| b01e7a29099f3eb8 | started | etcd-2 | https://192.168.80.46:2380 | https://192.168.80.46:2379 | false |
+------------------+---------+--------+----------------------------+----------------------------+------------+
# 3. 健康状态
etcdctl endpoint health --cacert=/etc/kubernetes/pki/ca.pem --cert=/etc/kubernetes/pki/etcd.pem --key=/etc/kubernetes/pki/etcd-key.pem --cluster --write-out=table
+----------------------------+--------+-------------+-------+
| ENDPOINT | HEALTH | TOOK | ERROR |
+----------------------------+--------+-------------+-------+
| https://192.168.80.47:2379 | true | 20.973639ms | |
| https://192.168.80.46:2379 | true | 29.842299ms | |
| https://192.168.80.45:2379 | true | 30.564766ms | |
+----------------------------+--------+-------------+-------+
5. Master 节点
kubernetes master 节点组件:
- kube-apiserver
- kube-scheduler
- kube-controller-manager
- kubelet (非必须,但必要)
- kube-proxy(非必须,但必要)
5.1 安装准备
https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.20.md
mkdir -p $HOME/k8s-install && cd $HOME/k8s-install
wget https://dl.k8s.io/v1.19.11/kubernetes-server-linux-amd64.tar.gz
tar zxvf kubernetes-server-linux-amd64.tar.gz
cd kubernetes/server/bin
cp kube-apiserver kube-scheduler kube-controller-manager kubectl kubelet kube-proxy /usr/bin
5.2 apiserver
5.2.1 TLS Bootstrapping Token
启用 TLS Bootstrapping 机制:
TLS Bootstraping:Master apiserver启用TLS认证后,Node节点kubelet和kube-proxy要与kube-apiserver进行通信,必须使用CA签发的有效证书才可以,当Node节点很多时,这种客户端证书颁发需要大量工作,同样也会增加集群扩展复杂度。为了简化流程,Kubernetes引入了TLS bootstraping机制来自动颁发客户端证书,kubelet会以一个低权限用户自动向apiserver申请证书,kubelet的证书由apiserver动态签署。所以强烈建议在Node上使用这种方式,目前主要用于kubelet,kube-proxy还是由我们统一颁发一个证书。
TLS bootstraping
工作流程:
BOOTSTRAP_TOKEN=$(head -c 16 /dev/urandom | od -An -t x | tr -d ' ')
# 格式:token,用户名,UID,用户组
cat > /etc/kubernetes/token.csv <<EOF
${BOOTSTRAP_TOKEN},kubelet-bootstrap,10001,"system:node-bootstrapper"
EOF
5.2.2 配置文件
--service-cluster-ip-range=10.254.0.0/16
: Service IP 段
cat > /etc/kubernetes/kube-apiserver.conf << EOF
KUBE_APISERVER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/var/log/kubernetes \\
--etcd-servers=https://192.168.80.45:2379,https://192.168.80.46:2379,https://192.168.80.47:2379 \\
--bind-address=192.168.80.45 \\
--secure-port=6443 \\
--advertise-address=192.168.80.45 \\
--allow-privileged=true \\
--service-cluster-ip-range=10.254.0.0/16 \\
--enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,ResourceQuota,NodeRestriction \\
--authorization-mode=RBAC,Node \\
--enable-bootstrap-token-auth=true \\
--token-auth-file=/etc/kubernetes/token.csv \\
--service-node-port-range=30000-32767 \\
--kubelet-client-certificate=/etc/kubernetes/pki/apiserver.pem \\
--kubelet-client-key=/etc/kubernetes/pki/apiserver-key.pem \\
--tls-cert-file=/etc/kubernetes/pki/apiserver.pem \\
--tls-private-key-file=/etc/kubernetes/pki/apiserver-key.pem \\
--client-ca-file=/etc/kubernetes/pki/ca.pem \\
--service-account-key-file=/etc/kubernetes/pki/ca-key.pem \\
--service-account-issuer=api \\
--service-account-signing-key-file=/etc/kubernetes/pki/apiserver-key.pem \\
--etcd-cafile=/etc/kubernetes/pki/ca.pem \\
--etcd-certfile=/etc/kubernetes/pki/etcd.pem \\
--etcd-keyfile=/etc/kubernetes/pki/etcd-key.pem \\
--requestheader-client-ca-file=/etc/kubernetes/pki/ca.pem \\
--proxy-client-cert-file=/etc/kubernetes/pki/apiserver.pem \\
--proxy-client-key-file=/etc/kubernetes/pki/apiserver-key.pem \\
--requestheader-allowed-names=kubernetes \\
--requestheader-extra-headers-prefix=X-Remote-Extra- \\
--requestheader-group-headers=X-Remote-Group \\
--requestheader-username-headers=X-Remote-User \\
--enable-aggregator-routing=true \\
--audit-log-maxage=30 \\
--audit-log-maxbackup=3 \\
--audit-log-maxsize=100 \\
--audit-log-path=/var/log/kubernetes/k8s-audit.log"
EOF
5.2.3 开机启动
# 1. 系统管理
cat > /lib/systemd/system/kube-apiserver.service << EOF
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/kubernetes/kubernetes
[Service]
EnvironmentFile=/etc/kubernetes/kube-apiserver.conf
ExecStart=/usr/bin/kube-apiserver \$KUBE_APISERVER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF
# 2. 启动
systemctl daemon-reload
systemctl start kube-apiserver
systemctl status kube-apiserver
systemctl enable kube-apiserver
5.3 controller-manager
5.3.1 kubeconfig 文件
KUBE_CONFIG="/etc/kubernetes/kube-controller-manager.kubeconfig"
KUBE_APISERVER="https://192.168.80.45:6443"
kubectl config set-cluster kubernetes \
--certificate-authority=/etc/kubernetes/pki/ca.pem \
--embed-certs=true \
--server=${KUBE_APISERVER} \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-controller-manager \
--client-certificate=/etc/kubernetes/pki/kube-controller-manager.pem \
--client-key=/etc/kubernetes/pki/kube-controller-manager-key.pem \
--embed-certs=true \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
--cluster=kubernetes \
--user=kube-controller-manager \
--kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}
5.3.2 配置文件
--cluster-cidr=10.244.0.0/16
: Pod IP 段
--service-cluster-ip-range=10.254.0.0/16
: Service IP 段
cat > /etc/kubernetes/kube-controller-manager.conf << EOF
KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/var/log/kubernetes \\
--leader-elect=true \\
--kubeconfig=/etc/kubernetes/kube-controller-manager.kubeconfig \\
--bind-address=127.0.0.1 \\
--allocate-node-cidrs=true \\
--cluster-cidr=10.244.0.0/16 \\
--service-cluster-ip-range=10.254.0.0/16 \\
--cluster-signing-cert-file=/etc/kubernetes/pki/ca.pem \\
--cluster-signing-key-file=/etc/kubernetes/pki/ca-key.pem \\
--root-ca-file=/etc/kubernetes/pki/ca.pem \\
--service-account-private-key-file=/etc/kubernetes/pki/ca-key.pem \\
--cluster-signing-duration=87600h0m0s"
EOF
5.3.3 开机启动
cat > /lib/systemd/system/kube-controller-manager.service << EOF
[Unit]
Description=Kubernetes Controller Manager
Documentation=https://github.com/kubernetes/kubernetes
[Service]
EnvironmentFile=-/etc/kubernetes/kube-controller-manager.conf
ExecStart=/usr/bin/kube-controller-manager \$KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl start kube-controller-manager
systemctl status kube-controller-manager
systemctl enable kube-controller-manager
5.4 scheduler
5.4.1 kubeconfig 文件
KUBE_CONFIG="/etc/kubernetes/kube-scheduler.kubeconfig"
KUBE_APISERVER="https://192.168.80.45:6443"
kubectl config set-cluster kubernetes \
--certificate-authority=/etc/kubernetes/pki/ca.pem \
--embed-certs=true \
--server=${KUBE_APISERVER} \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-scheduler \
--client-certificate=/etc/kubernetes/pki/kube-scheduler.pem \
--client-key=/etc/kubernetes/pki/kube-scheduler-key.pem \
--embed-certs=true \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
--cluster=kubernetes \
--user=kube-scheduler \
--kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}
5.4.2 配置文件
cat > /etc/kubernetes/kube-scheduler.conf << EOF
KUBE_SCHEDULER_OPTS="--logtostderr=false \
--v=2 \
--log-dir=/var/log/kubernetes \
--leader-elect \
--kubeconfig=/etc/kubernetes/kube-scheduler.kubeconfig \
--bind-address=127.0.0.1"
EOF
5.4.3 开机启动
cat > /lib/systemd/system/kube-scheduler.service << EOF
[Unit]
Description=Kubernetes Scheduler
Documentation=https://github.com/kubernetes/kubernetes
[Service]
EnvironmentFile=-/etc/kubernetes/kube-scheduler.conf
ExecStart=/usr/bin/kube-scheduler \$KUBE_SCHEDULER_OPTS
Restart=on-failure
[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl start kube-scheduler
systemctl status kube-scheduler
systemctl enable kube-scheduler
5.5 kubelet
5.5.1 参数配置文件
cat > /etc/kubernetes/kubelet-config.yml << EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: 0.0.0.0
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS:
- 10.254.0.2
clusterDomain: cluster.local
failSwapOn: false
authentication:
anonymous:
enabled: false
webhook:
cacheTTL: 2m0s
enabled: true
x509:
clientCAFile: /etc/kubernetes/pki/ca.pem
authorization:
mode: Webhook
webhook:
cacheAuthorizedTTL: 5m0s
cacheUnauthorizedTTL: 30s
evictionHard:
imagefs.available: 15%
memory.available: 100Mi
nodefs.available: 10%
nodefs.inodesFree: 5%
maxOpenFiles: 1000000
maxPods: 110
EOF
5.5.2 kubeconfig 文件
BOOTSTRAP_TOKEN=$(cat /etc/kubernetes/token.csv | awk -F, '{print $1}')
KUBE_CONFIG="/etc/kubernetes/bootstrap.kubeconfig"
KUBE_APISERVER="https://192.168.80.45:6443"
# 生成 kubelet bootstrap kubeconfig 配置文件
kubectl config set-cluster kubernetes \
--certificate-authority=/etc/kubernetes/pki/ca.pem \
--embed-certs=true \
--server=${KUBE_APISERVER} \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials "kubelet-bootstrap" \
--token=${BOOTSTRAP_TOKEN} \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
--cluster=kubernetes \
--user="kubelet-bootstrap" \
--kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}
5.5.3 配置文件
其中:--kubeconfig=/etc/kubernetes/kubelet.kubeconfig
在加入集群时自动生成
cat > /etc/kubernetes/kubelet.conf << EOF
KUBELET_OPTS="--logtostderr=false \\
--v=2 \\
--log-dir=/var/log/kubernetes \\
--hostname-override=k8s-master1 \\
--network-plugin=cni \\
--kubeconfig=/etc/kubernetes/kubelet.kubeconfig \\
--bootstrap-kubeconfig=/etc/kubernetes/bootstrap.kubeconfig \\
--config=/etc/kubernetes/kubelet-config.yml \\
--cert-dir=/etc/kubernetes/pki \\
--pod-infra-container-image=mirrorgooglecontainers/pause-amd64:3.1"
EOF
5.5.4 授权 kubelet-bootstrap 用户允许请求证书
防止错误:failed to run Kubelet: cannot create certificate signing request: certificatesigningrequests.certificates.k8s.io is forbidden: User "kubelet-bootstrap" cannot create resource "certificatesigningrequests" in API group "certificates.k8s.io" at the cluster scope
kubectl create clusterrolebinding kubelet-bootstrap \
--clusterrole=system:node-bootstrapper \
--user=kubelet-bootstrap
5.5.5 开机启动
cat > /lib/systemd/system/kubelet.service << EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
[Service]
EnvironmentFile=/etc/kubernetes/kubelet.conf
ExecStart=/usr/bin/kubelet \$KUBELET_OPTS
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl start kubelet
systemctl status kubelet
systemctl enable kubelet
5.5.6 加入集群
# 查看kubelet证书请求
kubectl get csr
NAME AGE SIGNERNAME REQUESTOR CONDITION
node-csr-ghWG-AWFM9sxJbr5A-BIq9puVIRxfFHrQlwDjYbHba8 25s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending
# 批准申请
kubectl certificate approve node-csr-ghWG-AWFM9sxJbr5A-BIq9puVIRxfFHrQlwDjYbHba8
# 再次查看证书
kubectl get csr
NAME AGE SIGNERNAME REQUESTOR CONDITION
node-csr-ghWG-AWFM9sxJbr5A-BIq9puVIRxfFHrQlwDjYbHba8 53m kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Approved,Issued
# 查看节点(由于网络插件还没有部署,节点会没有准备就绪 NotReady)
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 NotReady <none> 4m8s v1.19.11
5.6 kube-proxy
5.6.1 参数配置文件
clusterCIDR: 10.254.0.0/16
: Service IP 段,与apiserver & controller-manager 的--service-cluster-ip-range
一致
cat > /etc/kubernetes/kube-proxy-config.yml << EOF
kind: KubeProxyConfiguration
apiVersion: kubeproxy.config.k8s.io/v1alpha1
bindAddress: 0.0.0.0
metricsBindAddress: 0.0.0.0:10249
clientConnection:
kubeconfig: /etc/kubernetes/kube-proxy.kubeconfig
hostnameOverride: k8s-master1
clusterCIDR: 10.254.0.0/16
EOF
5.6.2 kubeconfig 文件
KUBE_CONFIG="/etc/kubernetes/kube-proxy.kubeconfig"
KUBE_APISERVER="https://192.168.80.45:6443"
kubectl config set-cluster kubernetes \
--certificate-authority=/etc/kubernetes/pki/ca.pem \
--embed-certs=true \
--server=${KUBE_APISERVER} \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials kube-proxy \
--client-certificate=/etc/kubernetes/pki/kube-proxy.pem \
--client-key=/etc/kubernetes/pki/kube-proxy-key.pem \
--embed-certs=true \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
--cluster=kubernetes \
--user=kube-proxy \
--kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}
5.6.3 配置文件
cat > /etc/kubernetes/kube-proxy.conf << EOF
KUBE_PROXY_OPTS="--logtostderr=false \
--v=2 \
--log-dir=/var/log/kubernetes \
--config=/etc/kubernetes/kube-proxy-config.yml"
EOF
5.6.4 开机启动
cat > /lib/systemd/system/kube-proxy.service << EOF
[Unit]
Description=Kubernetes Proxy
After=network.target
[Service]
EnvironmentFile=/etc/kubernetes/kube-proxy.conf
ExecStart=/usr/bin/kube-proxy \$KUBE_PROXY_OPTS
Restart=on-failure
LimitNOFILE=65536
[Install]
WantedBy=multi-user.target
EOF
systemctl daemon-reload
systemctl start kube-proxy
systemctl status kube-proxy
systemctl enable kube-proxy
5.7 授权 apiserver
访问 kubelet
mkdir -p $HOME/k8s-install && cd $HOME/k8s-install
cat > apiserver-to-kubelet-rbac.yaml << EOF
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
annotations:
rbac.authorization.kubernetes.io/autoupdate: "true"
labels:
kubernetes.io/bootstrapping: rbac-defaults
name: system:kube-apiserver-to-kubelet
rules:
- apiGroups:
- ""
resources:
- nodes/proxy
- nodes/stats
- nodes/log
- nodes/spec
- nodes/metrics
- pods/log
verbs:
- "*"
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: system:kube-apiserver
namespace: ""
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: system:kube-apiserver-to-kubelet
subjects:
- apiGroup: rbac.authorization.k8s.io
kind: User
name: kubernetes
EOF
kubectl apply -f apiserver-to-kubelet-rbac.yaml
5.8 集群管理
5.8.1 kubeconfig 文件
mkdir -p /root/.kube
KUBE_CONFIG=/root/.kube/config
KUBE_APISERVER="https://192.168.80.45:6443"
kubectl config set-cluster kubernetes \
--certificate-authority=/etc/kubernetes/pki/ca.pem \
--embed-certs=true \
--server=${KUBE_APISERVER} \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-credentials cluster-admin \
--client-certificate=/etc/kubernetes/pki/admin.pem \
--client-key=/etc/kubernetes/pki/admin-key.pem \
--embed-certs=true \
--kubeconfig=${KUBE_CONFIG}
kubectl config set-context default \
--cluster=kubernetes \
--user=cluster-admin \
--kubeconfig=${KUBE_CONFIG}
kubectl config use-context default --kubeconfig=${KUBE_CONFIG}
5.8.2 集群配置信息
kubectl config view
apiVersion: v1
clusters:
- cluster:
certificate-authority-data: DATA+OMITTED
server: https://192.168.80.45:6443
name: kubernetes
contexts:
- context:
cluster: kubernetes
user: cluster-admin
name: default
current-context: default
kind: Config
preferences: {}
users:
- name: cluster-admin
user:
client-certificate-data: REDACTED
client-key-data: REDACTED
5.8.3 集群状态
kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
scheduler Healthy ok
controller-manager Healthy ok
etcd-1 Healthy {"health":"true"}
etcd-2 Healthy {"health":"true"}
etcd-0 Healthy {"health":"true"}
5.9 命令补全
apt install -y bash-completion
source /usr/share/bash-completion/bash_completion
source <(kubectl completion bash)
echo "source <(kubectl completion bash)" >> ~/.bashrc
6. Node 节点
Kubernetes node节点组件:
- kubelet
- kube-proxy
6.1 克隆准备 (master节点执行)
mkdir -p $HOME/k8s-install && cd $HOME/k8s-install
tar cvf worker-node-clone.tar /usr/bin/{kubelet,kube-proxy} /lib/systemd/system/{kubelet,kube-proxy}.service /etc/kubernetes/kubelet* /etc/kubernetes/kube-proxy* /etc/kubernetes/pki /etc/kubernetes/bootstrap.kubeconfig
scp worker-node-clone.tar ubuntu@192.168.80.46:/home/ubuntu
scp worker-node-clone.tar ubuntu@192.168.80.47:/home/ubuntu
6.2 克隆节点
cd / && mv /home/ubuntu/worker-node-clone.tar / && tar xvf worker-node-clone.tar && rm -f worker-node-clone.tar
# 删除证书申请审批后自动生成的文件,后面重新生成
rm -f /etc/kubernetes/kubelet.kubeconfig
rm -f /etc/kubernetes/pki/kubelet*
# 日志目录
mkdir -p /var/log/kubernetes
6.3 修改配置
按实际节点名称修改
# kubelet
vi /etc/kubernetes/kubelet.conf
--hostname-override=k8s-node01
# kube-proxy
vi /etc/kubernetes/kube-proxy-config.yml
hostnameOverride: k8s-node01
6.4 开机启动
systemctl daemon-reload
systemctl start kubelet kube-proxy
systemctl status kubelet kube-proxy
systemctl enable kubelet kube-proxy
6.5 加入集群 (master节点执行)
# 1. 节点信息
kubectl get csr
NAME AGE SIGNERNAME REQUESTOR CONDITION
node-csr-ghWG-AWFM9sxJbr5A-BIq9puVIRxfFHrQlwDjYbHba8 94m kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Approved,Issued
node-csr-r2GF_8R3zuUe9BCf6eHeijWnzyPDDy-6WQUFOrOAQjA 34s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending
node-csr-wvcKDHm38jQgjyaLiA_G2ycc2Qvmecf_iRRd9IqlSEw 97s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending
# 2. 批准加入
kubectl certificate approve node-csr-r2GF_8R3zuUe9BCf6eHeijWnzyPDDy-6WQUFOrOAQjA
kubectl certificate approve node-csr-wvcKDHm38jQgjyaLiA_G2ycc2Qvmecf_iRRd9IqlSEw
# 3. 集群节点
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 NotReady <none> 45m v1.19.11
k8s-node01 NotReady <none> 6s v1.19.11
k8s-node02 NotReady <none> 10s v1.19.11
# 4. 设置标签,即更改节点角色
kubectl label node k8s-master1 node-role.kubernetes.io/master=
kubectl label node k8s-node01 node-role.kubernetes.io/node=
kubectl label node k8s-node02 node-role.kubernetes.io/node=
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 NotReady master 49m v1.19.11
k8s-node01 NotReady node 3m45s v1.19.11
k8s-node02 NotReady node 3m49s v1.19.11
# 5. 设置污点:是master节点无法创建pod
kubectl taint nodes k8s-master1 node-role.kubernetes.io/master=:NoSchedule
kubectl describe node k8s-master1
Taints: node-role.kubernetes.io/master:NoSchedule
node.kubernetes.io/not-ready:NoSchedule
7. CNI 网络
# 节点状态
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 NotReady master 49m v1.19.11
k8s-node01 NotReady node 3m45s v1.19.11
k8s-node02 NotReady node 3m49s v1.19.11
# 检查日志,发现网络插件未安装
journalctl -u kubelet -f
Jun 02 14:24:29 k8s-master1 kubelet[75636]: W0602 14:24:29.172144 75636 cni.go:239] Unable to update cni config: no networks found in /etc/cni/net.d
Jun 02 14:24:32 k8s-master1 kubelet[75636]: E0602 14:24:32.958021 75636 kubelet.go:2129] Container runtime network not ready: NetworkReady=false reason:NetworkPluginNotReady message:docker: network plugin is not ready: cni config uninitialized
其中涉及的IP段,要与 kube-controller-manager中 “–cluster-cidr” 一致
7.1 安装 CNI 网络插件
所有节点都要操作
mkdir -p $HOME/k8s-install/network && cd $_
wget https://github.com/containernetworking/plugins/releases/download/v0.9.1/cni-plugins-linux-amd64-v0.9.1.tgz
mkdir -p /opt/cni/bin
tar zxvf cni-plugins-linux-amd64-v0.9.1.tgz -C /opt/cni/bin
7.2 calico
Calico
是一个纯三层的数据中心网络方案,是目前Kubernetes主流的网络方案。
mkdir -p $HOME/k8s-install/network && cd $HOME/k8s-install/network
# 1. 下载插件
wget https://docs.projectcalico.org/manifests/calico.yaml
# CIDR的值,与 kube-controller-manager中“--cluster-cidr=10.244.0.0/16” 一致
vi calico.yaml
3680 # The default IPv4 pool to create on startup if none exists. Pod IPs will be
3681 # chosen from this range. Changing this value after installation will have
3682 # no effect. This should fall within `--cluster-cidr`.
3683 - name: CALICO_IPV4POOL_CIDR
3684 value: "10.244.0.0/16"
# 2. 安装网络插件
kubectl apply -f calico.yaml
# 3. 检查是否启动
kubectl get pod -n kube-system
NAME READY STATUS RESTARTS AGE
calico-kube-controllers-7f4f5bf95d-tgklk 1/1 Running 0 2m7s
calico-node-fwv5x 1/1 Running 0 2m8s
calico-node-ttt2c 1/1 Running 0 2m8s
calico-node-xjvjf 1/1 Running 0 2m8s
# 4. 节点状态正常
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready master 65m v1.19.11
k8s-node01 Ready node 20m v1.19.11
k8s-node02 Ready node 20m v1.19.11
7.3 flannel
mkdir -p $HOME/k8s-install/network && cd $HOME/k8s-install/network
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
kubectl apply -f kube-flannel.yml
vi kube-flannel.yml
"Network": "10.244.0.0/16",
kubectl get pod -n kube-system
NAME READY STATUS RESTARTS AGE
kube-flannel-ds-8qnnx 1/1 Running 0 10s
kube-flannel-ds-979lc 1/1 Running 0 16m
kube-flannel-ds-kgmgg 1/1 Running 0 16m
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready master 85m v1.19.11
k8s-node01 Ready node 40m v1.19.11
k8s-node02 Ready node 40m v1.19.11
8. Addons
8.1 CoreDNS
CoreDNS用于集群内部Service名称解析
mkdir -p $HOME/k8s-install/coredns && cd $HOME/k8s-install/coredns
wget https://raw.githubusercontent.com/coredns/deployment/master/kubernetes/coredns.yaml.sed
wget https://raw.githubusercontent.com/coredns/deployment/master/kubernetes/deploy.sh
chmod +x deploy.sh
export CLUSTER_DNS_SVC_IP="10.254.0.2"
export CLUSTER_DNS_DOMAIN="cluster.local"
./deploy.sh -i ${CLUSTER_DNS_SVC_IP} -d ${CLUSTER_DNS_DOMAIN} | kubectl apply -f -
# 查询状态
kubectl get pods -n kube-system | grep coredns
coredns-746fcb4bc5-nts2k 1/1 Running 0 6m2s
# 验证 busybox1.33.1有问题
kubectl run -it --rm dns-test --image=busybox:1.28.4 /bin/sh
If you don't see a command prompt, try pressing enter.
/ # nslookup kubernetes
Server: 10.254.0.2
Address: 10.254.0.2:53
Name: kubernetes.default.svc.cluster.local
Address: 10.0.0.1
DNS问题排查:
# dns service
kubectl get svc -n kube-system
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kube-dns ClusterIP 10.254.0.2 <none> 53/UDP,53/TCP,9153/TCP 13m
# endpoints 是否正常
kubectl get endpoints kube-dns -n kube-system
NAME ENDPOINTS AGE
kube-dns 10.244.85.194:53,10.244.85.194:53,10.244.85.194:9153 13m
# coredns 增加解析日志
CoreDNS 配置参数说明:
errors: 输出错误信息到控制台。
health:CoreDNS 进行监控检测,检测地址为 http://localhost:8080/health 如果状态为不健康则让 Pod 进行重启。
ready: 全部插件已经加载完成时,将通过 endpoints 在 8081 端口返回 HTTP 状态 200。
kubernetes:CoreDNS 将根据 Kubernetes 服务和 pod 的 IP 回复 DNS 查询。
prometheus:是否开启 CoreDNS Metrics 信息接口,如果配置则开启,接口地址为 http://localhost:9153/metrics
forward:任何不在Kubernetes 集群内的域名查询将被转发到预定义的解析器 (/etc/resolv.conf)。
cache:启用缓存,30 秒 TTL。
loop:检测简单的转发循环,如果找到循环则停止 CoreDNS 进程。
reload:监听 CoreDNS 配置,如果配置发生变化则重新加载配置。
loadbalance:DNS 负载均衡器,默认 round_robin。
# 编辑 coredns 配置
kubectl edit configmap coredns -n kube-system
apiVersion: v1
data:
Corefile: |
.:53 {
log # new add
errors
health {
lameduck 5s
}
ready
kubernetes cluster.local in-addr.arpa ip6.arpa {
fallthrough in-addr.arpa ip6.arpa
}
prometheus :9153
forward . /etc/resolv.conf {
max_concurrent 1000
}
cache 30
loop
reload
loadbalance
}
kind: ConfigMap
metadata:
annotations:
kubectl.kubernetes.io/last-applied-configuration: |
{"apiVersion":"v1","data":{"Corefile":".:53 {\n errors\n health {\n lameduck 5s\n }\n ready\n kubernetes cluster.local in-addr.arpa ip6.arpa {\n fallthrough in-addr.arpa ip6.arpa\n }\n prometheus :9153\n forward . /etc/resolv.conf {\n max_concurrent 1000\n }\n cache 30\n loop\n reload\n loadbalance\n}\n"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"coredns","namespace":"kube-system"}}
creationTimestamp: "2021-05-13T11:57:45Z"
name: coredns
namespace: kube-system
resourceVersion: "38460"
selfLink: /api/v1/namespaces/kube-system/configmaps/coredns
uid: c62a856d-1fc3-4fe9-b5f1-3ca0dbeb39c1
回滚操作:
wget https://raw.githubusercontent.com/coredns/deployment/master/kubernetes/rollback.sh
chmod +x rollback.sh
export CLUSTER_DNS_SVC_IP="10.254.0.2"
export CLUSTER_DNS_DOMAIN="cluster.local"
./rollback.sh -i ${CLUSTER_DNS_SVC_IP} -d ${CLUSTER_DNS_DOMAIN} | kubectl apply -f -
kubectl delete --namespace=kube-system deployment coredns
8.2 Dashboard
mkdir -p $HOME/k8s-install/dashboard && cd $HOME/k8s-install/dashboard
# 1. 下载并安装
curl https://raw.githubusercontent.com/kubernetes/dashboard/v2.2.0/aio/deploy/recommended.yaml -o dashboard.yaml
kubectl apply -f dashboard.yaml
# 2. 检查运行状态
kubectl get pods -n kubernetes-dashboard -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
dashboard-metrics-scraper-79c5968bdc-xkm78 1/1 Running 0 23m 10.244.159.129 k8s-master1 <none> <none>
kubernetes-dashboard-9f9799597-d8g8t 1/1 Running 0 23m 10.244.58.193 k8s-node02 <none> <none>
# 3. 检查服务状态
kubectl get svc -n kubernetes-dashboard -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
dashboard-metrics-scraper ClusterIP 10.254.14.1 <none> 8000/TCP 24m k8s-app=dashboard-metrics-scraper
kubernetes-dashboard ClusterIP 10.254.219.125 <none> 443/TCP 24m k8s-app=kubernetes-dashboard
# 4. 服务改为NodePort方式
kubectl edit svc kubernetes-dashboard -n kubernetes-dashboard
type: ClusterIP => type: NodePort
kubectl get svc -n kubernetes-dashboard -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
dashboard-metrics-scraper ClusterIP 10.254.14.1 <none> 8000/TCP 3h30m k8s-app=dashboard-metrics-scraper
kubernetes-dashboard NodePort 10.254.219.125 <none> 443:31639/TCP 3h30m k8s-app=kubernetes-dashboard
# 5. 创建service account并绑定默认cluster-admin管理员集群角色:
kubectl create serviceaccount dashboard-admin -n kube-system
kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
# 6. 获取访问 token
kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')
Name: dashboard-admin-token-xwd72
Namespace: kube-system
Labels: <none>
Annotations: kubernetes.io/service-account.name: dashboard-admin
kubernetes.io/service-account.uid: 013e9f84-827f-4dc7-81b3-874a28bfebc6
Type: kubernetes.io/service-account-token
Data
====
ca.crt: 1310 bytes
namespace: 11 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6InNQRElCQTlPRUZ5SU54STQ1QWllLXlKMTFCcmZieG0wVTJnRlpzYlBNLXcifQ.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.O-DI-0IlLFP2pDRKzQYJrZeDAnVvW1IjU-iVwGzvwID7BH0v6kXfWnti07qm8VkuGFJtpuQsmrf6v4sUeRDhr95kZlEVV8Rxnes6oixrkXdk3fR4xreh4lh6ZgCzbER6xI8pMG-j9KNjTRdY6gQPJuOThtI9ab13dpTT5AYpggA2O98DFfgcJ_DzD05hhk6TghOdoro00msHRSUrsEiH0CYa_3PiyPlkvmmY3MlJPsBTdO2pCDzcrjQ2L5EaJAvSh6OodkRY6ymOwfcbfPs3WwSocCEfwkogYOCAQhMC4NU3Jea_hoeFqzLdS1PK5R2rPT-wqemwjDKn0E6jUv6juw
# 7. 访问
https://192.168.80.45:31639
9. 高可用
角色 | IP | 组件 | 备注 |
---|---|---|---|
k8s-master1 | 192.168.80.45 | etcd, api-server, controller-manager, scheduler, kubelet, kube-proxy, docker | |
k8s-node01 | 192.168.80.46 | etcd, kubelet, kube-proxy, docker | |
k8s-node02 | 192.168.80.47 | etcd, kubelet, kube-proxy, docker | |
k8s-master2 | 192.168.80.49 | etcd, api-server, controller-manager, scheduler, kubelet, kube-proxy, docker | 新增节点 |
9.1 准备操作 (Master-1)
9.1.1 kube-apiserver 证书更新
在新增节点的IP段未在证书中时需要如下操作:
mkdir -p /root/ssl && cd /root/ssl
# 1. 证书签名请求文件
cat > apiserver-csr.json <<EOF
{
"CN": "kubernetes",
"hosts": [
"127.0.0.1",
"localhost",
"192.168.80.1",
"192.168.80.2",
"192.168.80.3",
"192.168.80.45",
"192.168.80.46",
"192.168.80.47",
"192.168.80.48",
"192.168.80.49",
"10.254.0.1",
"kubernetes",
"kubernetes.default",
"kubernetes.default.svc",
"kubernetes.default.svc.cluster",
"kubernetes.default.svc.cluster.local"
],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "k8s",
"OU": "System"
}
]
}
EOF
# 2. 生成证书
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes apiserver-csr.json | cfssljson -bare apiserver
# 3. 证书更新
cp apiserver*.pem /etc/kubernetes/pki
scp apiserver*.pem ubuntu@192.168.80.46:/home/ubuntu
scp apiserver*.pem ubuntu@192.168.80.47:/home/ubuntu
# 4. node节点证书更新
chown root:root /home/ubuntu/apiserver*.pem
mv /home/ubuntu/apiserver*.pem /etc/kubernetes/pki
# 5. 重启 apiserver
systemctl restart kube-apiserver
systemctl status kube-apiserver
9.1.2 增加主机
在 k8s-master1, k8s-node01, k8s-node02 上制作
echo '192.168.80.49 k8s-master2' >> /etc/hosts
9.2 扩容 Master
9.2.1 初始化
# 1. 修改主机名
hostnamectl set-hostname k8s-master2
# 2. 主机名解析
cat >> /etc/hosts <<EOF
192.168.80.45 k8s-master1
192.168.80.46 k8s-node01
192.168.80.47 k8s-node02
192.168.80.49 k8s-master2
EOF
# 3. 禁用 swap
swapoff -a && sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab
# 4. 将桥接的IPv4流量传递到iptables的链
cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system
# 5. 域名解析
echo "nameserver 8.8.8.8" >> /etc/resolv.conf
# 6. 时间同步
apt install ntpdate -y
ntpdate ntp1.aliyun.com
crontab -e
*/30 * * * * /usr/sbin/ntpdate-u ntp1.aliyun.com >> /var/log/ntpdate.log 2>&1
# 7. 日志目录
mkdir -p /var/log/kubernetes
9.2.2 克隆
# 1. k8s-master1 上执行
mkdir -p $HOME/k8s-install && cd $HOME/k8s-install
tar zcvf master-node-clone.tar.gz /usr/bin/kube* /lib/systemd/system/kube*.service /etc/kubernetes /root/.kube/config /usr/bin/docker* /usr/bin/runc /usr/bin/containerd* /usr/bin/ctr /etc/docker /lib/systemd/system/docker.service
scp master-node-clone.tar.gz ubuntu@192.168.80.49:/home/ubuntu
# 2. k8s-master2 执行
cd / && mv /home/ubuntu/master-node-clone.tar.gz / && tar zxvf master-node-clone.tar.gz && rm -f master-node-clone.tar.gz
rm -f /etc/kubernetes/kubelet.kubeconfig
rm -f /etc/kubernetes/pki/kubelet*
9.2.3 更新配置
vi /etc/kubernetes/kube-apiserver.conf
--bind-address=192.168.80.49 \
--advertise-address=192.168.80.49 \
sed -i 's#k8s-master1#k8s-master2#' /etc/kubernetes/*
sed -i 's#192.168.80.45:6443#192.168.80.49:6443#' /etc/kubernetes/*
vi /root/.kube/config
server: https://192.168.80.49:6443
9.2.4 开机启动
systemctl daemon-reload
systemctl start docker kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
systemctl status docker kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
systemctl enable docker kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
9.2.5 集群状态
kubectl get cs
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME STATUS MESSAGE ERROR
controller-manager Healthy ok
scheduler Healthy ok
etcd-2 Healthy {"health":"true"}
etcd-1 Healthy {"health":"true"}
etcd-0 Healthy {"health":"true"}
9.2.6 加入集群
kubectl get csr
NAME AGE SIGNERNAME REQUESTOR CONDITION
node-csr-HfzAqSEc7sIIG9QFHip4vGFnFZhyZnYjBVGWQyGpz54 7m49s kubernetes.io/kube-apiserver-client-kubelet kubelet-bootstrap Pending
# 批准加入
kubectl certificate approve node-csr-HfzAqSEc7sIIG9QFHip4vGFnFZhyZnYjBVGWQyGpz54
kubectl get node
NAME STATUS ROLES AGE VERSION
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready master 27h v1.19.11
k8s-master2 NotReady <none> 11s v1.19.11
k8s-node01 Ready node 27h v1.19.11
k8s-node02 Ready node 27h v1.19.11
9.2.7 打标和污点
# 设置标签
kubectl label node k8s-master2 node-role.kubernetes.io/master=
# 设置污点:是master节点无法创建pod
kubectl taint nodes k8s-master2 node-role.kubernetes.io/master=:NoSchedule
# 节点信息
kubectl get nodes --show-labels
NAME STATUS ROLES AGE VERSION LABELS
k8s-master1 Ready master 27h v1.19.11 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-master1,kubernetes.io/os=linux,node-role.kubernetes.io/master=
k8s-master2 Ready master 2m13s v1.19.11 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-master2,kubernetes.io/os=linux,node-role.kubernetes.io/master=
k8s-node01 Ready node 27h v1.19.11 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-node01,kubernetes.io/os=linux,node-role.kubernetes.io/node=
k8s-node02 Ready node 27h v1.19.11 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=k8s-node02,kubernetes.io/os=linux,node-role.kubernetes.io/node=
9.3 高可用负载均衡
Nginx
: 主流Web服务和反向代理服务器,这里用四层实现对apiserver实现负载均衡。
Keepalived
: 主流高可用软件,基于VIP绑定实现服务器双机热备。Keepalived主要根据Nginx运行状态判断是否需要故障转移(漂移VIP),例如当Nginx主节点挂掉,VIP会自动绑定在Nginx备节点,从而保证VIP一直可用,实现Nginx高可用。
服务器规划:
角色 | IP | 组件 |
---|---|---|
k8s-master1 | 192.168.80.45 | kube-apiserver |
k8s-master2 | 192.168.80.49 | kube-apiserver |
k8s-loadbalancer1 | 192.168.80.2 | nginx, keepalived |
k8s-loadbalancer2 | 192.168.80.3 | nginx, keepalived |
VIP | 192.168.80.1 | 虚拟IP |
9.3.1 安装软件
apt install nginx keepalived -y
9.3.2 配置Nginx
cat > /etc/nginx/nginx.conf << "EOF"
user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;
include /usr/share/nginx/modules/*.conf;
events {
worker_connections 1024;
}
stream {
log_format main '$remote_addr $upstream_addr - [$time_local] $status $upstream_bytes_sent';
access_log /var/log/nginx/k8s-access.log main;
upstream k8s-apiserver {
server 192.168.80.45:6443; # Master1 APISERVER IP:PORT
server 192.168.80.49:6443; # Master2 APISERVER IP:PORT
}
server {
listen 16443;
proxy_pass k8s-apiserver;
}
}
http {
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/nginx/access.log main;
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;
include /etc/nginx/mime.types;
default_type application/octet-stream;
server {
listen 80 default_server;
server_name _;
location / {
}
}
}
EOF
9.3.3 keepalived 配置 (master)
cat > /etc/keepalived/keepalived.conf << EOF
global_defs {
notification_email {
acassen@firewall.loc
failover@firewall.loc
sysadmin@firewall.loc
}
notification_email_from Alexandre.Cassen@firewall.loc
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id NGINX_MASTER
}
# 检查脚本
vrrp_script check_nginx {
script "/etc/keepalived/check_nginx.sh"
}
vrrp_instance VI_1 {
state MASTER
interface ens33 # 修改为实际网卡名
virtual_router_id 51 # VRRP 路由 ID实例,每个实例是唯一的
priority 100 # 优先级,备服务器设置 90
advert_int 1 # 指定VRRP 心跳包通告间隔时间,默认1秒
authentication {
auth_type PASS
auth_pass 1111
}
# 虚拟IP
virtual_ipaddress {
192.168.80.1/24
}
track_script {
check_nginx
}
}
EOF
9.3.4 keepalived 配置 (slave)
cat > /etc/keepalived/keepalived.conf << EOF
global_defs {
notification_email {
acassen@firewall.loc
failover@firewall.loc
sysadmin@firewall.loc
}
notification_email_from Alexandre.Cassen@firewall.loc
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id NGINX_BACKUP
}
# 检查脚本
vrrp_script check_nginx {
script "/etc/keepalived/check_nginx.sh"
}
vrrp_instance VI_1 {
state BACKUP
interface ens33 # 修改为实际网卡名
virtual_router_id 51 # VRRP 路由 ID实例,每个实例是唯一的
priority 90 # 优先级,备服务器设置 90
advert_int 1 # 指定VRRP 心跳包通告间隔时间,默认1秒
authentication {
auth_type PASS
auth_pass 1111
}
# 虚拟IP
virtual_ipaddress {
192.168.80.1/24
}
track_script {
check_nginx
}
}
EOF
9.3.5 keepalived 检查脚本
cat > /etc/keepalived/check_nginx.sh << "EOF"
#!/bin/bash
count=$(ss -antp |grep 16443 |egrep -cv "grep|$$")
if [ "$count" -eq 0 ];then
exit 1
else
exit 0
fi
EOF
chmod +x /etc/keepalived/check_nginx.sh
9.3.6 启动服务
systemctl daemon-reload
systemctl start nginx keepalived
systemctl enable nginx keepalived
9.3.7 状态检查
ip addr
curl -k https://192.168.80.1:16443/version
{
"major": "1",
"minor": "19",
"gitVersion": "v1.19.11",
"gitCommit": "c6a2f08fc4378c5381dd948d9ad9d1080e3e6b33",
"gitTreeState": "clean",
"buildDate": "2021-05-12T12:19:22Z",
"goVersion": "go1.15.12",
"compiler": "gc",
"platform": "linux/amd64"
}
9.3.8 Worker Node 连接到 LB VIP
sed -i 's#192.168.80.45:6443#192.168.80.1:16443#' /etc/kubernetes/*
systemctl restart kubelet kube-proxy
kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready master 3d17h v1.19.11
k8s-master2 Ready master 2d16h v1.19.11
k8s-node01 Ready node 3d15h v1.19.11
k8s-node02 Ready node 3d15h v1.19.11
10. 删除节点
# 1. k8s-master2 上,停止kubelet进程
systemctl stop kubelet
# 2. 检查 k8s-master2 是否已下线
kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready master 40h v1.19.11
k8s-master2 NotReady master 12h v1.19.11
k8s-node01 Ready node 40h v1.19.11
k8s-node02 Ready node 40h v1.19.11
# 3. 删除节点
kubectl drain k8s-master2
node/k8s-master2 cordoned
error: unable to drain node "k8s-master2", aborting command...
There are pending nodes to be drained:
k8s-master2
error: cannot delete DaemonSet-managed Pods (use --ignore-daemonsets to ignore): kube-system/calico-node-lwj2r
# 4. 强制下线
kubectl drain k8s-master2 --ignore-daemonsets
node/k8s-master2 already cordoned
WARNING: ignoring DaemonSet-managed Pods: kube-system/calico-node-lwj2r
node/k8s-master2 drained
# 5. 下线状态
kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready master 40h v1.19.11
k8s-master2 Ready,SchedulingDisabled master 12h v1.19.11
k8s-node01 Ready node 39h v1.19.11
k8s-node02 Ready node 39h v1.19.11
# 6. 恢复操作 (如有必要)
kubectl uncordon k8s-master2
node/k8s-master2 uncordoned
kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready master 40h v1.19.11
k8s-master2 Ready master 12h v1.19.11
k8s-node01 Ready node 39h v1.19.11
k8s-node02 Ready node 39h v1.19.11
# 7. 彻底删除
kubectl delete node k8s-master2
kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master1 Ready master 41h v1.19.11
k8s-node01 Ready node 40h v1.19.11
k8s-node02 Ready node 40h v1.19.11
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