kubernetes 1.6 集群实践 (六)

kubernetes master 节点包含的组件

这三个组件需要部署在同一台机器上,三者的功能紧密相关

  • kube-apiserver
  • kube-scheduler
  • kube-controller-manager

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;

下载编译好的二进制文件

在github寻找合适的链接下载:
https://github.com/kubernetes/kubernetes/releases
这个包里面有master节点组件的全部文件
kubernetes-server-linux-amd64.tar.gz

拷贝到系统命令目录下,并给予执行权限

$ tar xf kubernetes-server-linux-amd64.tar.gz
$ cd kubernetes/server/bin
$ cp {kube-apiserver,kube-controller-manager,kube-scheduler,kubectl,kube-proxy,kubelet} /usr/bin/
$ chmod +x /usr/bin/kube*

创建 kube-apiserver的配置文件

创建systemd 启动文件

$ cat > /usr/lib/systemd/system/kube-apiserver.service << EOF
[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/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
EOF

创建配置文件 /etc/kubernetes/config文件配置如下:

该配置文件同时被kube-apiserver、kube-controller-manager、kube-scheduler、kubelet、kube-proxy使用。

cat > /etc/kubernetes/config << EOF
###
# 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://192.168.19.101:8080"
EOF

KUBE_LOGTOSTDERR 日志设置

KUBE_LOG_LEVEL 日志级别设置

KUBE_ALLOW_PRIV 是否运行运行特殊的Docker容器

KUBE_MASTER 主节点的地址,主要为replication controller和scheduler,kube-proxy可以顺利找到apiserver,使用端口是本地主机端口由apiserver的--insecure-port 和--insecure-bind-address 定义

创建apiserver专用的配置文件/etc/kubernetes/apiserver内容为

cat > /etc/kubernetes/apiserver << EOF
###
## 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=192.168.19.101 --bind-address=192.168.19.101 --insecure-bind-address=192.168.19.101"
#
## 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://192.168.19.101:2379,https://192.168.19.102:2379,https://192.168.19.103:2379"
#
## 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"
EOF

--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;

--insecure-port 默认端口为8080,--secure-port默认端口为6443,--secure-port端口由node节点的kubelet或其他工具调用。

创建kube-controller-manager的配置文件

创建systemd启动文件

$ cat >/usr/lib/systemd/system/kube-controller-manager.service << EOF
Description=Kubernetes Controller Manager
Documentation=https://github.com/GoogleCloudPlatform/kubernetes

[Service]
EnvironmentFile=-/etc/kubernetes/config
EnvironmentFile=-/etc/kubernetes/controller-manager
ExecStart=/usr/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
EOF

创建kube-controller-manager专用的配置文件/etc/kubernetes/controller-manager内容为

$ cat >/etc/kubernetes/controller-manager <<EOF
###
# 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-cidr=10.250.0.0/16  --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"
EOF

--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-cidr 参数制定pod的网段

--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,因为当前 kube-apiserver 期望 scheduler 和 controller-manager 在同一台机器

创建kube-scheduler的配置文件

创建systemd启动文件

$ cat > /usr/lib/systemd/system/kube-scheduler.service << EOF
[Unit]
Description=Kubernetes Scheduler Plugin
Documentation=https://github.com/GoogleCloudPlatform/kubernetes

[Service]
EnvironmentFile=-/etc/kubernetes/config
EnvironmentFile=-/etc/kubernetes/scheduler
ExecStart=/usr/bin/kube-scheduler 
            $KUBE_LOGTOSTDERR 
            $KUBE_LOG_LEVEL 
            $KUBE_MASTER 
            $KUBE_SCHEDULER_ARGS
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

创建kube-scheduler专用的配置文件/etc/kubernetes/scheduler内容为

$ cat > /etc/kubernetes/scheduler << EOF
###
# kubernetes scheduler config

# default config should be adequate

# Add your own!
KUBE_SCHEDULER_ARGS="--leader-elect=true --address=127.0.0.1"
EOF

--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

启动master服务

$ systemctl daemon-reload && systemctl start kube-apiserver && systemctl start kube-controller-manager && systemctl start kube-scheduler

严重master是否健康

$ kubectl get componentstatuses
NAME                 STATUS    MESSAGE              ERROR
scheduler            Healthy   ok                   
controller-manager   Healthy   ok                   
etcd-0               Healthy   {"health": "true"}   

原文地址:https://www.cnblogs.com/panjunbai/p/8372568.html