318 lines
12 KiB
Markdown
318 lines
12 KiB
Markdown
# 部署master节点
|
||
|
||
kubernetes master 节点包含的组件：
|
||
|
||
+ kube-apiserver
|
||
+ kube-scheduler
|
||
+ kube-controller-manager
|
||
|
||
目前这三个组件需要部署在同一台机器上。
|
||
|
||
+ `kube-scheduler`、`kube-controller-manager` 和 `kube-apiserver` 三者的功能紧密相关；
|
||
+ 同时只能有一个 `kube-scheduler`、`kube-controller-manager` 进程处于工作状态，如果运行多个，则需要通过选举产生一个 leader；
|
||
|
||
**注**：
|
||
|
||
- 暂时未实现master节点的高可用
|
||
- master节点上没有部署flannel网络插件，如果想要在master节点上也能访问ClusterIP，请参考下一节[部署node节点](node-installation.md)中的配置Flanneld部分。
|
||
|
||
## TLS 证书文件
|
||
|
||
以下`pem`证书文件我们在[创建TLS证书和秘钥](create-tls-and-secret-key.md)这一步中已经创建过了，`token.csv`文件在[创建kubeconfig文件](create-kubeconfig.md)的时候创建。我们再检查一下。
|
||
|
||
``` bash
|
||
$ ls /etc/kubernetes/ssl
|
||
admin-key.pem admin.pem ca-key.pem ca.pem kube-proxy-key.pem kube-proxy.pem kubernetes-key.pem kubernetes.pem
|
||
```
|
||
|
||
## 下载最新版本的二进制文件
|
||
|
||
有两种下载方式，请注意下载对应的Kubernetes版本。
|
||
|
||
**方式一**
|
||
|
||
从 [github release 页面](https://github.com/kubernetes/kubernetes/releases) 下载发布版 tarball，解压后再执行下载脚本
|
||
|
||
``` bash
|
||
wget https://github.com/kubernetes/kubernetes/releases/download/v1.6.0/kubernetes.tar.gz
|
||
tar -xzvf kubernetes.tar.gz
|
||
cd kubernetes
|
||
./cluster/get-kube-binaries.sh
|
||
```
|
||
**方式二**
|
||
|
||
从 [`CHANGELOG`页面](https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG.md) 下载 `client` 或 `server` tarball 文件
|
||
|
||
`server` 的 tarball `kubernetes-server-linux-amd64.tar.gz` 已经包含了 `client`(`kubectl`) 二进制文件，所以不用单独下载`kubernetes-client-linux-amd64.tar.gz`文件；
|
||
|
||
``` shell
|
||
# wget https://dl.k8s.io/v1.6.0/kubernetes-client-linux-amd64.tar.gz
|
||
wget https://dl.k8s.io/v1.6.0/kubernetes-server-linux-amd64.tar.gz
|
||
tar -xzvf kubernetes-server-linux-amd64.tar.gz
|
||
cd kubernetes
|
||
tar -xzvf kubernetes-src.tar.gz
|
||
```
|
||
将二进制文件拷贝到指定路径
|
||
|
||
``` bash
|
||
cp -r server/bin/{kube-apiserver,kube-controller-manager,kube-scheduler,kubectl,kube-proxy,kubelet} /usr/local/bin/
|
||
```
|
||
|
||
## 配置和启动 kube-apiserver
|
||
|
||
**创建 kube-apiserver的service配置文件**
|
||
|
||
service配置文件`/usr/lib/systemd/system/kube-apiserver.service`内容：
|
||
|
||
```ini
|
||
[Unit]
|
||
Description=Kubernetes API Service
|
||
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
|
||
After=network.target
|
||
After=etcd.service
|
||
|
||
[Service]
|
||
EnvironmentFile=-/etc/kubernetes/config
|
||
EnvironmentFile=-/etc/kubernetes/apiserver
|
||
ExecStart=/usr/local/bin/kube-apiserver \
|
||
$KUBE_LOGTOSTDERR \
|
||
$KUBE_LOG_LEVEL \
|
||
$KUBE_ETCD_SERVERS \
|
||
$KUBE_API_ADDRESS \
|
||
$KUBE_API_PORT \
|
||
$KUBELET_PORT \
|
||
$KUBE_ALLOW_PRIV \
|
||
$KUBE_SERVICE_ADDRESSES \
|
||
$KUBE_ADMISSION_CONTROL \
|
||
$KUBE_API_ARGS
|
||
Restart=on-failure
|
||
Type=notify
|
||
LimitNOFILE=65536
|
||
|
||
[Install]
|
||
WantedBy=multi-user.target
|
||
```
|
||
|
||
`/etc/kubernetes/config`文件的内容为：
|
||
|
||
```ini
|
||
###
|
||
# kubernetes system config
|
||
#
|
||
# The following values are used to configure various aspects of all
|
||
# kubernetes services, including
|
||
#
|
||
# kube-apiserver.service
|
||
# kube-controller-manager.service
|
||
# kube-scheduler.service
|
||
# kubelet.service
|
||
# kube-proxy.service
|
||
# logging to stderr means we get it in the systemd journal
|
||
KUBE_LOGTOSTDERR="--logtostderr=true"
|
||
|
||
# journal message level, 0 is debug
|
||
KUBE_LOG_LEVEL="--v=0"
|
||
|
||
# Should this cluster be allowed to run privileged docker containers
|
||
KUBE_ALLOW_PRIV="--allow-privileged=true"
|
||
|
||
# How the controller-manager, scheduler, and proxy find the apiserver
|
||
#KUBE_MASTER="--master=http://sz-pg-oam-docker-test-001.tendcloud.com:8080"
|
||
KUBE_MASTER="--master=http://172.20.0.113:8080"
|
||
```
|
||
|
||
该配置文件同时被kube-apiserver、kube-controller-manager、kube-scheduler、kubelet、kube-proxy使用。
|
||
|
||
apiserver配置文件`/etc/kubernetes/apiserver`内容为：
|
||
|
||
``` Ini
|
||
###
|
||
## kubernetes system config
|
||
##
|
||
## The following values are used to configure the kube-apiserver
|
||
##
|
||
#
|
||
## The address on the local server to listen to.
|
||
#KUBE_API_ADDRESS="--insecure-bind-address=sz-pg-oam-docker-test-001.tendcloud.com"
|
||
KUBE_API_ADDRESS="--advertise-address=172.20.0.113 --bind-address=172.20.0.113 --insecure-bind-address=172.20.0.113"
|
||
#
|
||
## The port on the local server to listen on.
|
||
#KUBE_API_PORT="--port=8080"
|
||
#
|
||
## Port minions listen on
|
||
#KUBELET_PORT="--kubelet-port=10250"
|
||
#
|
||
## Comma separated list of nodes in the etcd cluster
|
||
KUBE_ETCD_SERVERS="--etcd-servers=https://172.20.0.113:2379,https://172.20.0.114:2379,https://172.20.0.115:2379"
|
||
#
|
||
## Address range to use for services
|
||
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"
|
||
#
|
||
## default admission control policies
|
||
KUBE_ADMISSION_CONTROL="--admission-control=ServiceAccount,NamespaceLifecycle,NamespaceExists,LimitRanger,ResourceQuota"
|
||
#
|
||
## Add your own!
|
||
KUBE_API_ARGS="--authorization-mode=RBAC --runtime-config=rbac.authorization.k8s.io/v1beta1 --kubelet-https=true --experimental-bootstrap-token-auth --token-auth-file=/etc/kubernetes/token.csv --service-node-port-range=30000-32767 --tls-cert-file=/etc/kubernetes/ssl/kubernetes.pem --tls-private-key-file=/etc/kubernetes/ssl/kubernetes-key.pem --client-ca-file=/etc/kubernetes/ssl/ca.pem --service-account-key-file=/etc/kubernetes/ssl/ca-key.pem --etcd-cafile=/etc/kubernetes/ssl/ca.pem --etcd-certfile=/etc/kubernetes/ssl/kubernetes.pem --etcd-keyfile=/etc/kubernetes/ssl/kubernetes-key.pem --enable-swagger-ui=true --apiserver-count=3 --audit-log-maxage=30 --audit-log-maxbackup=3 --audit-log-maxsize=100 --audit-log-path=/var/lib/audit.log --event-ttl=1h"
|
||
```
|
||
|
||
+ `--experimental-bootstrap-token-auth` Bootstrap Token Authentication在1.9版本已经变成了正式feature，参数名称改为`--enable-bootstrap-token-auth`
|
||
+ 如果中途修改过`--service-cluster-ip-range`地址，则必须将default命名空间的`kubernetes`的service给删除，使用命令：`kubectl delete service kubernetes`，然后系统会自动用新的ip重建这个service，不然apiserver的log有报错`the cluster IP x.x.x.x for service kubernetes/default is not within the service CIDR x.x.x.x/16; please recreate`
|
||
+ `--authorization-mode=RBAC` 指定在安全端口使用 RBAC 授权模式，拒绝未通过授权的请求；
|
||
+ kube-scheduler、kube-controller-manager 一般和 kube-apiserver 部署在同一台机器上，它们使用**非安全端口**和 kube-apiserver通信;
|
||
+ kubelet、kube-proxy、kubectl 部署在其它 Node 节点上，如果通过**安全端口**访问 kube-apiserver，则必须先通过 TLS 证书认证，再通过 RBAC 授权；
|
||
+ kube-proxy、kubectl 通过在使用的证书里指定相关的 User、Group 来达到通过 RBAC 授权的目的；
|
||
+ 如果使用了 kubelet TLS Boostrap 机制，则不能再指定 `--kubelet-certificate-authority`、`--kubelet-client-certificate` 和 `--kubelet-client-key` 选项，否则后续 kube-apiserver 校验 kubelet 证书时出现 ”x509: certificate signed by unknown authority“ 错误；
|
||
+ `--admission-control` 值必须包含 `ServiceAccount`；
|
||
+ `--bind-address` 不能为 `127.0.0.1`；
|
||
+ `runtime-config`配置为`rbac.authorization.k8s.io/v1beta1`，表示运行时的apiVersion；
|
||
+ `--service-cluster-ip-range` 指定 Service Cluster IP 地址段，该地址段不能路由可达；
|
||
+ 缺省情况下 kubernetes 对象保存在 etcd `/registry` 路径下，可以通过 `--etcd-prefix` 参数进行调整；
|
||
+ 如果需要开通http的无认证的接口，则可以增加以下两个参数：`--insecure-port=8080 --insecure-bind-address=127.0.0.1`。注意，生产上不要绑定到非127.0.0.1的地址上
|
||
|
||
**Kubernetes 1.9**
|
||
|
||
对于Kubernetes1.9集群，需要注意配置`KUBE_API_ARGS`环境变量中的`--authorization-mode=Node,RBAC`，增加对`Node`授权的模式，否则将无法注册node。
|
||
|
||
完整 unit 见 [kube-apiserver.service](../systemd/kube-apiserver.service)
|
||
|
||
**启动kube-apiserver**
|
||
|
||
``` bash
|
||
systemctl daemon-reload
|
||
systemctl enable kube-apiserver
|
||
systemctl start kube-apiserver
|
||
systemctl status kube-apiserver
|
||
```
|
||
|
||
## 配置和启动 kube-controller-manager
|
||
|
||
**创建 kube-controller-manager的serivce配置文件**
|
||
|
||
文件路径`/usr/lib/systemd/system/kube-controller-manager.service`
|
||
|
||
```ini
|
||
[Unit]
|
||
Description=Kubernetes Controller Manager
|
||
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
|
||
|
||
[Service]
|
||
EnvironmentFile=-/etc/kubernetes/config
|
||
EnvironmentFile=-/etc/kubernetes/controller-manager
|
||
ExecStart=/usr/local/bin/kube-controller-manager \
|
||
$KUBE_LOGTOSTDERR \
|
||
$KUBE_LOG_LEVEL \
|
||
$KUBE_MASTER \
|
||
$KUBE_CONTROLLER_MANAGER_ARGS
|
||
Restart=on-failure
|
||
LimitNOFILE=65536
|
||
|
||
[Install]
|
||
WantedBy=multi-user.target
|
||
```
|
||
|
||
配置文件`/etc/kubernetes/controller-manager`。
|
||
|
||
``` ini
|
||
###
|
||
# The following values are used to configure the kubernetes controller-manager
|
||
|
||
# defaults from config and apiserver should be adequate
|
||
|
||
# Add your own!
|
||
KUBE_CONTROLLER_MANAGER_ARGS="--address=127.0.0.1 --service-cluster-ip-range=10.254.0.0/16 --cluster-name=kubernetes --cluster-signing-cert-file=/etc/kubernetes/ssl/ca.pem --cluster-signing-key-file=/etc/kubernetes/ssl/ca-key.pem --service-account-private-key-file=/etc/kubernetes/ssl/ca-key.pem --root-ca-file=/etc/kubernetes/ssl/ca.pem --leader-elect=true"
|
||
```
|
||
|
||
+ `--service-cluster-ip-range` 参数指定 Cluster 中 Service 的CIDR范围，该网络在各 Node 间必须路由不可达，必须和 kube-apiserver 中的参数一致；
|
||
+ `--cluster-signing-*` 指定的证书和私钥文件用来签名为 TLS BootStrap 创建的证书和私钥；
|
||
+ `--root-ca-file` 用来对 kube-apiserver 证书进行校验，**指定该参数后，才会在Pod 容器的 ServiceAccount 中放置该 CA 证书文件**；
|
||
+ `--address` 值必须为 `127.0.0.1`，kube-apiserver 期望 scheduler 和 controller-manager 在同一台机器；
|
||
|
||
|
||
### 启动 kube-controller-manager
|
||
|
||
``` bash
|
||
systemctl daemon-reload
|
||
systemctl enable kube-controller-manager
|
||
systemctl start kube-controller-manager
|
||
systemctl status kube-controller-manager
|
||
```
|
||
|
||
我们启动每个组件后可以通过执行命令`kubectl get componentstatuses`，来查看各个组件的状态;
|
||
|
||
```bash
|
||
$ kubectl get componentstatuses
|
||
NAME STATUS MESSAGE ERROR
|
||
scheduler Unhealthy Get http://127.0.0.1:10251/healthz: dial tcp 127.0.0.1:10251: getsockopt: connection refused
|
||
controller-manager Healthy ok
|
||
etcd-2 Healthy {"health": "true"}
|
||
etcd-0 Healthy {"health": "true"}
|
||
etcd-1 Healthy {"health": "true"}
|
||
```
|
||
|
||
- 如果有组件report unhealthy请参考：https://github.com/kubernetes-incubator/bootkube/issues/64
|
||
|
||
完整 unit 见 [kube-controller-manager.service](../systemd/kube-controller-manager.service)
|
||
|
||
## 配置和启动 kube-scheduler
|
||
|
||
**创建 kube-scheduler的serivce配置文件**
|
||
|
||
文件路径`/usr/lib/systemd/system/kube-scheduler.service`。
|
||
|
||
```ini
|
||
[Unit]
|
||
Description=Kubernetes Scheduler Plugin
|
||
Documentation=https://github.com/GoogleCloudPlatform/kubernetes
|
||
|
||
[Service]
|
||
EnvironmentFile=-/etc/kubernetes/config
|
||
EnvironmentFile=-/etc/kubernetes/scheduler
|
||
ExecStart=/usr/local/bin/kube-scheduler \
|
||
$KUBE_LOGTOSTDERR \
|
||
$KUBE_LOG_LEVEL \
|
||
$KUBE_MASTER \
|
||
$KUBE_SCHEDULER_ARGS
|
||
Restart=on-failure
|
||
LimitNOFILE=65536
|
||
|
||
[Install]
|
||
WantedBy=multi-user.target
|
||
```
|
||
|
||
配置文件`/etc/kubernetes/scheduler`。
|
||
|
||
``` Ini
|
||
###
|
||
# kubernetes scheduler config
|
||
|
||
# default config should be adequate
|
||
|
||
# Add your own!
|
||
KUBE_SCHEDULER_ARGS="--leader-elect=true --address=127.0.0.1"
|
||
```
|
||
|
||
+ `--address` 值必须为 `127.0.0.1`，因为当前 kube-apiserver 期望 scheduler 和 controller-manager 在同一台机器；
|
||
|
||
完整 unit 见 [kube-scheduler.service](../systemd/kube-scheduler.service)
|
||
|
||
### 启动 kube-scheduler
|
||
|
||
``` bash
|
||
systemctl daemon-reload
|
||
systemctl enable kube-scheduler
|
||
systemctl start kube-scheduler
|
||
systemctl status kube-scheduler
|
||
```
|
||
|
||
## 验证 master 节点功能
|
||
|
||
``` bash
|
||
$ kubectl get componentstatuses
|
||
NAME STATUS MESSAGE ERROR
|
||
scheduler Healthy ok
|
||
controller-manager Healthy ok
|
||
etcd-0 Healthy {"health": "true"}
|
||
etcd-1 Healthy {"health": "true"}
|
||
etcd-2 Healthy {"health": "true"}
|
||
```
|