k8s集群二进制部署过程

服务器

浏览数:8

2019-11-2

1.部署ETCd集群
下载cfssl工具:

wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64
wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64
wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64
chmod +x cfssl_linux-amd64 cfssljson_linux-amd64 cfssl-certinfo_linux-amd64
mv cfssl_linux-amd64 /usr/local/bin/cfssl
mv cfssljson_linux-amd64 /usr/local/bin/cfssljson
mv cfssl-certinfo_linux-amd64 /usr/bin/cfssl-certinfo

生成Etcd证书:
创建以下三个文件:

vim ca-config.json
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "www": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}

vim ca-csr.json
{
    "CN": "etcd CA",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing"
        }
    ]
}

修改etcd集群的主机IP地址
vim server-csr.json
{
    "CN": "etcd",
    "hosts": [
    "192.168.135.128",
    "192.168.135.129",
    "192.168.135.130"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing"
        }
    ]
}

生成证书:

# cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
# cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=www server-csr.json | cfssljson -bare server
# ls *pem
ca-key.pem  ca.pem  server-key.pem  server.pem

安装Etcd:
二进制包下载地址:

    https://github.com/coreos/etcd/releases/tag/v3.2.12
    wget https://github.com/etcd-io/etcd/releases/download/v3.2.12/etcd-v3.2.12-linux-amd64.tar.gz

以下部署步骤在规划的三个etcd节点操作一样,唯一不同的是etcd配置文件中的服务器IP要写当前的:
解压二进制包:

mkdir /opt/etcd/{bin,cfg,ssl} -p
tar zxvf etcd-v3.2.12-linux-amd64.tar.gz
mv etcd-v3.2.12-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/

创建etcd配置文件:
cat >>  /opt/etcd/cfg/etcd <EOF  
#[Member]
ETCD_NAME="etcd01"
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="https://192.168.0.196:2380"
ETCD_LISTEN_CLIENT_URLS="https://192.168.0.196:2379"

#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.0.196:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://192.168.0.196:2379"
ETCD_INITIAL_CLUSTER="etcd01=https://192.168.0.196:2380,etcd02=https://192.168.0.144:2380,etcd03=https://192.168.0.156:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
EOF

* ETCD_NAME 节点名称
* ETCD_DATA_DIR 数据目录
* ETCD_LISTEN_PEER_URLS 集群通信监听地址
* ETCD_LISTEN_CLIENT_URLS 客户端访问监听地址
* ETCD_INITIAL_ADVERTISE_PEER_URLS 集群通告地址
* ETCD_ADVERTISE_CLIENT_URLS 客户端通告地址
* ETCD_INITIAL_CLUSTER 集群节点地址
* ETCD_INITIAL_CLUSTER_TOKEN 集群Token
* ETCD_INITIAL_CLUSTER_STATE 加入集群的当前状态,new是新集群,existing表示加入已有集群

systemd管理etcd:

vim /usr/lib/systemd/system/etcd.service 
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target

[Service]
Type=notify
EnvironmentFile=/opt/etcd/cfg/etcd
ExecStart=/opt/etcd/bin/etcd \
--name=${ETCD_NAME} \
--data-dir=${ETCD_DATA_DIR} \
--listen-peer-urls=${ETCD_LISTEN_PEER_URLS} \
--listen-client-urls=${ETCD_LISTEN_CLIENT_URLS},http://127.0.0.1:2379 \
--advertise-client-urls=${ETCD_ADVERTISE_CLIENT_URLS} \
--initial-advertise-peer-urls=${ETCD_INITIAL_ADVERTISE_PEER_URLS} \
--initial-cluster=${ETCD_INITIAL_CLUSTER} \
--initial-cluster-token=${ETCD_INITIAL_CLUSTER_TOKEN} \
--initial-cluster-state=new \
--cert-file=/opt/etcd/ssl/server.pem \
--key-file=/opt/etcd/ssl/server-key.pem \
--peer-cert-file=/opt/etcd/ssl/server.pem \
--peer-key-file=/opt/etcd/ssl/server-key.pem \
--trusted-ca-file=/opt/etcd/ssl/ca.pem \
--peer-trusted-ca-file=/opt/etcd/ssl/ca.pem
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

把刚才生成的证书拷贝到配置文件中的位置:

# cp ca*pem server*pem /opt/etcd/ssl

启动并设置开启启动:

# systemctl start etcd
# systemctl enable etcd

都部署完成后,检查etcd集群状态:

# /opt/etcd/bin/etcdctl \
--ca-file=/opt/etcd/ssl/ca.pem --cert-file=/opt/etcd/ssl/server.pem --key-file=/opt/etcd/ssl/server-key.pem \
--endpoints="https://192.168.135.128:2379,https://192.168.135.129:2379,https://192.168.135.130:2379" \
cluster-health
member 4101e54b63ca7b19 is healthy: got healthy result from https://192.168.135.129:2379
member 5a58f66f830ba739 is healthy: got healthy result from https://192.168.135.128:2379
member 67e264f60acc1d51 is healthy: got healthy result from https://192.168.135.130:2379
cluster is healthy

如果输出上面信息,就说明集群部署成功。

——————————————-在Node节点安装Docker———————————————————-

yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager \
    --add-repo \
    https://download.docker.com/linux/centos/docker-ce.repo
yum install docker-ce -y
curl -sSL https://get.daocloud.io/daotools/set_mirror.sh | sh -s http://bc437cce.m.daocloud.io
systemctl start docker
systemctl enable docker

——————————————-部署Flannel网络———————————————————-

Falnnel要用etcd存储自身一个子网信息,所以要保证能成功连接Etcd,写入预定义子网段:

# /opt/etcd/bin/etcdctl \
--ca-file=ca.pem --cert-file=server.pem --key-file=server-key.pem \
--endpoints="https://192.168.135.128:2379,https://192.168.135.129:2379,https://192.168.135.130:2379" \
set /coreos.com/network/config  '{ "Network": "172.17.0.0/16", "Backend": {"Type": "vxlan"}}'

以下部署步骤在规划的每个node节点都操作。
下载二进制包:

wget https://github.com/coreos/flannel/releases/download/v0.10.0/flannel-v0.10.0-linux-amd64.tar.gz
tar zxvf flannel-v0.10.0-linux-amd64.tar.gz
mkdir -pv /opt/kubernetes/bin
mv flanneld mk-docker-opts.sh /opt/kubernetes/bin

配置Flannel:

# mkdir -pv /opt/kubernetes/cfg/
# vim /opt/kubernetes/cfg/flanneld
FLANNEL_OPTIONS="--etcd-endpoints=https://192.168.135.128:2379,https://192.168.135.129:2379,https://192.168.135.130:2379 -etcd-cafile=/opt/etcd/ssl/ca.pem -etcd-certfile=/opt/etcd/ssl/server.pem -etcd-keyfile=/opt/etcd/ssl/server-key.pem"

systemd管理Flannel:

# cat >>  /usr/lib/systemd/system/flanneld.service <EOF
[Unit]
Description=Flanneld overlay address etcd agent
After=network-online.target network.target
Before=docker.service

[Service]
Type=notify
EnvironmentFile=/opt/kubernetes/cfg/flanneld
ExecStart=/opt/kubernetes/bin/flanneld --ip-masq $FLANNEL_OPTIONS
ExecStartPost=/opt/kubernetes/bin/mk-docker-opts.sh -k DOCKER_NETWORK_OPTIONS -d /run/flannel/subnet.env
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

配置Docker启动指定子网段:

cat  >>   /usr/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
EnvironmentFile=/run/flannel/subnet.env
ExecStart=/usr/bin/dockerd $DOCKER_NETWORK_OPTIONS
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

从其他节点拷贝证书文件到node1和2上:因为node1和2上没有证书,但是flanel需要证书

mkdir -pv /opt/etcd/ssl/
scp /opt/etcd/ssl/*  k8s-node2:/opt/etcd/ssl/

重启flannel和docker:
systemctl daemon-reload
systemctl start flanneld
systemctl enable flanneld
systemctl restart docker

检查是否生效:

ps -ef |grep docker
root     20941     1  1 Jun28 ?        09:15:34 /usr/bin/dockerd --bip=172.17.34.1/24 --ip-masq=false --mtu=1450
ip addr
3607: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN 
    link/ether 8a:2e:3d:09:dd:82 brd ff:ff:ff:ff:ff:ff
    inet 172.17.34.0/32 scope global flannel.1
       valid_lft forever preferred_lft forever
3608: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UP 
    link/ether 02:42:31:8f:d3:02 brd ff:ff:ff:ff:ff:ff
    inet 172.17.34.1/24 brd 172.17.34.255 scope global docker0
       valid_lft forever preferred_lft forever
    inet6 fe80::42:31ff:fe8f:d302/64 scope link 
       valid_lft forever preferred_lft forever
    

确保docker0与flannel.1在同一网段。
测试不同节点互通,在当前节点访问另一个Node节点docker0 IP:

# ping 172.17.58.1
PING 172.17.58.1 (172.17.58.1) 56(84) bytes of data.
64 bytes from 172.17.58.1: icmp_seq=1 ttl=64 time=0.263 ms
64 bytes from 172.17.58.1: icmp_seq=2 ttl=64 time=0.204 ms

如果能通说明Flannel部署成功。如果不通检查下日志:journalctl -u flannel

在Master节点部署组件:
两个Master节点部署方式一样

在部署Kubernetes之前一定要确保etcd、flannel、docker是正常工作的,否则先解决问题再继续。

生成证书
创建CA证书:

cat >> ca-config.json < EOF
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "kubernetes": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF

cat >>  ca-csr.json < EOF
{
    "CN": "kubernetes",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF

cfssl gencert -initca ca-csr.json | cfssljson -bare ca -

生成apiserver证书:
cat >>  server-csr.json < EOF
{
    "CN": "kubernetes",
    "hosts": [
      "10.0.0.1",//这是后面dns要使用的虚拟网络的网关,不用改,就用这个  切忌(删除这行)
      "127.0.0.1",
      "192.168.135.128",
      "192.168.135.129",
      "195.168.135.130",
      "kubernetes",
      "kubernetes.default",
      "kubernetes.default.svc",
      "kubernetes.default.svc.cluster",
      "kubernetes.default.svc.cluster.local"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "BeiJing",
            "ST": "BeiJing",
            "O": "k8s",
            "OU": "System"
        }
    ]
}
EOF

cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes server-csr.json | cfssljson -bare server

生成kube-proxy证书:
cat >>  kube-proxy-csr.json < EOF
{
  "CN": "system:kube-proxy",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "L": "BeiJing",
      "ST": "BeiJing",
      "O": "k8s",
      "OU": "System"
    }
  ]
}
EOF

cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy

最终生成以下证书文件:

# ls *pem
ca-key.pem  ca.pem  kube-proxy-key.pem  kube-proxy.pem  server-key.pem  server.pem

部署apiserver组件
下载二进制包:

https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.11.md  下载这个包(kubernetes-server-linux-amd64.tar.gz)就够了,包含了所需的所有组件。
 wget https://dl.k8s.io/v1.11.10/kubernetes-server-linux-amd64.tar.gz

mkdir /opt/kubernetes/{bin,cfg,ssl} -pv
tar zxvf kubernetes-server-linux-amd64.tar.gz
cd kubernetes/server/bin
cp kube-apiserver kube-scheduler kube-controller-manager kubectl /opt/kubernetes/bin

从生成证书的机器拷贝证书到master1,master2:

scp server.pem  server-key.pem ca.pem ca-key.pem k8s-master1:/opt/kubernetes/ssl/
scp server.pem  server-key.pem ca.pem ca-key.pem k8s-master2:/opt/kubernetes/ssl/

创建token文件

cat >>  /opt/kubernetes/cfg/token.csv <EOF
674c457d4dcf2eefe4920d7dbb6b0ddc,kubelet-bootstrap,10001,"system:kubelet-bootstrap"
EOF

第一列:随机字符串,自己可生成第二列:用户名第三列:UID第四列:用户组

创建apiserver配置文件:

cat >>  /opt/kubernetes/cfg/kube-apiserver  < EOF 

KUBE_APISERVER_OPTS="--logtostderr=true \
--v=4 \
--etcd-servers=https://192.168.135.128:2379,https://192.168.135.129:2379,https://192.168.135.130:2379 \
--bind-address=192.168.135.128 \
--secure-port=6443 \
--advertise-address=192.168.135.128 \
--allow-privileged=true \
--service-cluster-ip-range=10.0.0.0/24 \
--enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,ResourceQuota,NodeRestriction \
--authorization-mode=RBAC,Node \
--enable-bootstrap-token-auth \
--token-auth-file=/opt/kubernetes/cfg/token.csv \
--service-node-port-range=30000-50000 \
--tls-cert-file=/opt/kubernetes/ssl/server.pem  \
--tls-private-key-file=/opt/kubernetes/ssl/server-key.pem \
--client-ca-file=/opt/kubernetes/ssl/ca.pem \
--service-account-key-file=/opt/kubernetes/ssl/ca-key.pem \
--etcd-cafile=/opt/etcd/ssl/ca.pem \
--etcd-certfile=/opt/etcd/ssl/server.pem \
--etcd-keyfile=/opt/etcd/ssl/server-key.pem"
EOF

配置好前面生成的证书,确保能连接etcd。

参数说明:
* --logtostderr 启用日志
* --v 日志等级
* --etcd-servers etcd集群地址
* --bind-address 监听地址
* --secure-port https安全端口
* --advertise-address 集群通告地址
* --allow-privileged 启用授权
* --service-cluster-ip-range Service虚拟IP地址段
* --enable-admission-plugins 准入控制模块
* --authorization-mode 认证授权,启用RBAC授权和节点自管理
* --enable-bootstrap-token-auth 启用TLS bootstrap功能,后面会讲到
* --token-auth-file token文件
* --service-node-port-range Service Node类型默认分配端口范围

systemd管理apiserver:

cat >>  /usr/lib/systemd/system/kube-apiserver.service < EOF 
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/kubernetes/kubernetes

[Service]
EnvironmentFile=-/opt/kubernetes/cfg/kube-apiserver
ExecStart=/opt/kubernetes/bin/kube-apiserver $KUBE_APISERVER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

启动:

systemctl daemon-reload
systemctl enable kube-apiserver
systemctl start kube-apiserver

部署schduler组件创建schduler配置文件

cat > /opt/kubernetes/cfg/kube-scheduler < EOF 

KUBE_SCHEDULER_OPTS="--logtostderr=true \
--v=4 \
--master=127.0.0.1:8080 \
--leader-elect"
EOF

参数说明:
* --master 连接本地apiserver
* --leader-elect 当该组件启动多个时,自动选举(HA)

systemd管理schduler组件:

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

[Service]
EnvironmentFile=-/opt/kubernetes/cfg/kube-scheduler
ExecStart=/opt/kubernetes/bin/kube-scheduler $KUBE_SCHEDULER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF
启动:
 systemctl daemon-reload
 systemctl enable kube-scheduler 
 systemctl start kube-scheduler 

部署controller-manager组件
创建controller-manager配置文件:

cat >  /opt/kubernetes/cfg/kube-controller-manager < EOF 
KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=true \
--v=4 \
--master=127.0.0.1:8080 \
--leader-elect=true \
--address=127.0.0.1 \
--service-cluster-ip-range=10.0.0.0/24 \ 
--cluster-name=kubernetes \
--cluster-signing-cert-file=/opt/kubernetes/ssl/ca.pem \
--cluster-signing-key-file=/opt/kubernetes/ssl/ca-key.pem  \
--root-ca-file=/opt/kubernetes/ssl/ca.pem \
--service-account-private-key-file=/opt/kubernetes/ssl/ca-key.pem"
EOF

systemd管理controller-manager组件:

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

[Service]
EnvironmentFile=-/opt/kubernetes/cfg/kube-controller-manager
ExecStart=/opt/kubernetes/bin/kube-controller-manager $KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF
启动:
systemctl daemon-reload
systemctl enable kube-controller-manager
systemctl start kube-controller-manager

所有组件都已经启动成功,通过kubectl工具查看当前集群组件状态:

ln -s  /opt/kubernetes/bin/kubectl  /usr/bin/
kubectl get cs
NAME                 STATUS    MESSAGE             ERROR
scheduler            Healthy   ok                  
etcd-0               Healthy   {"health":"true"}   
etcd-2               Healthy   {"health":"true"}   
etcd-1               Healthy   {"health":"true"}   
controller-manager   Healthy   ok
如上输出说明组件都正常。

———————————–下面这些操作在master节点完成:——————————————–
将kubelet-bootstrap用户绑定到系统集群角色

/opt/kubernetes/bin/kubectl create clusterrolebinding kubelet-bootstrap \
  --clusterrole=system:node-bootstrapper \
  --user=kubelet-bootstrap

创建kubeconfig文件:
在生成kubernetes证书的目录下执行以下命令生成kubeconfig文件:

指定apiserver 地址(如果apiserver做了负载均衡,则填写负载均衡地址)
KUBE_APISERVER="https://192.168.135.128:6443"
BOOTSTRAP_TOKEN=674c457d4dcf2eefe4920d7dbb6b0ddc
设置集群参数
/opt/kubernetes/bin/kubectl config set-cluster kubernetes \
  --certificate-authority=./ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=bootstrap.kubeconfig

设置客户端认证参数
/opt/kubernetes/bin/kubectl config set-credentials kubelet-bootstrap \
  --token=${BOOTSTRAP_TOKEN} \
  --kubeconfig=bootstrap.kubeconfig

设置上下文参数
/opt/kubernetes/bin/kubectl config set-context default \
  --cluster=kubernetes \
  --user=kubelet-bootstrap \
  --kubeconfig=bootstrap.kubeconfig

设置默认上下文
/opt/kubernetes/bin/kubectl config use-context default --kubeconfig=bootstrap.kubeconfig

———————-

创建kube-proxy kubeconfig文件

/opt/kubernetes/bin/kubectl config set-cluster kubernetes \
  --certificate-authority=./ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=kube-proxy.kubeconfig

/opt/kubernetes/bin/kubectl config set-credentials kube-proxy \
  --client-certificate=./kube-proxy.pem \
  --client-key=./kube-proxy-key.pem \
  --embed-certs=true \
  --kubeconfig=kube-proxy.kubeconfig

/opt/kubernetes/bin/kubectl config set-context default \
  --cluster=kubernetes \
  --user=kube-proxy \
  --kubeconfig=kube-proxy.kubeconfig

/opt/kubernetes/bin/kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig

# ls
bootstrap.kubeconfig  kube-proxy.kubeconfig
坑:将这两个文件拷贝到Node节点/opt/kubernetes/cfg目录下。

———————-下面这些操作在node节点完成:—————————
部署kubelet组件
将前面下载的二进制包中的kubelet和kube-proxy拷贝到/opt/kubernetes/bin目录下。
创建kubelet配置文件:

cat >  /opt/kubernetes/cfg/kubelet < EOF
KUBELET_OPTS="--logtostderr=true \
--v=4 \
--hostname-override=192.168.135.129 \
--kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig \
--bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig \
--config=/opt/kubernetes/cfg/kubelet.config \
--cert-dir=/opt/kubernetes/ssl \
--pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0"
EOF

参数说明:
* --hostname-override 在集群中显示的主机名
* --kubeconfig 指定kubeconfig文件位置,会自动生成
* --bootstrap-kubeconfig 指定刚才生成的bootstrap.kubeconfig文件
* --cert-dir 颁发证书存放位置
* --pod-infra-container-image 管理Pod网络的镜像

其中/opt/kubernetes/cfg/kubelet.config配置文件如下:

cat >  /opt/kubernetes/cfg/kubelet.config  < EOF
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: 192.168.135.129
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS: ["10.0.0.2"]
clusterDomain: cluster.local.
failSwapOn: false
authentication:
  anonymous:
    enabled: true 
  webhook:
    enabled: false
EOF

systemd管理kubelet组件:

cat > /usr/lib/systemd/system/kubelet.service   < EOF
[Unit]
Description=Kubernetes Kubelet
After=docker.service
Requires=docker.service

[Service]
EnvironmentFile=/opt/kubernetes/cfg/kubelet
ExecStart=/opt/kubernetes/bin/kubelet $KUBELET_OPTS
Restart=on-failure
KillMode=process

[Install]
WantedBy=multi-user.target
EOF

启动:

systemctl daemon-reload
systemctl enable kubelet
systemctl start kubelet

在Master审批Node加入集群:
启动后还没加入到集群中,需要手动允许该节点才可以。在Master节点查看请求签名的Node:

/opt/kubernetes/bin/kubectl get csr
/opt/kubernetes/bin/kubectl certificate approve XXXXID
/opt/kubernetes/bin/kubectl get node

部署kube-proxy组件
创建kube-proxy配置文件:

cat >  /opt/kubernetes/cfg/kube-proxy  < EOF
KUBE_PROXY_OPTS="--logtostderr=true \
--v=4 \
--hostname-override=192.168.135.129 \
--cluster-cidr=10.0.0.0/24 \           //不要改,就是这个ip
--kubeconfig=/opt/kubernetes/cfg/kube-proxy.kubeconfig"
EOF

systemd管理kube-proxy组件:

cat >  /usr/lib/systemd/system/kube-proxy.service < EOF 
[Unit]
Description=Kubernetes Proxy
After=network.target

[Service]
EnvironmentFile=-/opt/kubernetes/cfg/kube-proxy
ExecStart=/opt/kubernetes/bin/kube-proxy $KUBE_PROXY_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target
EOF

启动:

systemctl daemon-reload
systemctl enable kube-proxy
systemctl start kube-proxy

查看集群状态

# /opt/kubernetes/bin/kubectl get node
NAME             STATUS    ROLES     AGE       VERSION
10.206.240.111   Ready     <none>    28d       v1.11.0
10.206.240.112   Ready     <none>    28d       v1.11.0
# /opt/kubernetes/bin/kubectl get cs
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"}

运行一个测试示例
创建一个Nginx Web,判断集群是否正常工作:

# /opt/kubernetes/bin/kubectl run nginx --image=nginx --replicas=3
# /opt/kubernetes/bin/kubectl expose deployment nginx --port=88 --target-port=80 --type=NodePort

查看Pod,Service:

# /opt/kubernetes/bin/kubectl get pods
NAME                       READY     STATUS    RESTARTS   AGE
nginx-64f497f8fd-fjgt2      1/1      Running     3        28d
nginx-64f497f8fd-gmstq      1/1      Running     3        28d
nginx-64f497f8fd-q6wk9      1/1      Running     3        28d

查看pod详细信息:

# /opt/kubernetes/bin/kubectl describe nginx-64f497f8fd-fjgt2 
# /opt/kubernetes/bin/kubectl get svc
NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)                        AGE
kubernetes   ClusterIP   10.0.0.1     <none>        443/TCP                        28d
nginx        NodePort    10.0.0.175   <none>        88:38696/TCP                   28d

打开浏览器输入:http://10.206.240.111:38696

编写yaml文件内容如下:
---
apiVersion: v1
kind: Pod
metadata:
  name: kube100-site
  labels:
    app: web
    app1: abc234     //labels里面标签的值不能是纯数字
spec:
  containers:
    - name: front-end 
      image: daocloud.io/library/nginx
      ports:
        - containerPort: 80

创建Pod:

# kubectl apply -f pod.yaml
pod "kube100-site" created

查看pod状态

通过get命令来查看被创建的pod。
如果执行完创建pod的命令之后,你的速度足够快,那么使用get命令你将会看到以下的状态:
# kubectl get pods
NAME          READY     STATUS    RESTARTS   AGE
hello-world   0/1       Pending   0          0s

# kubectl get pods
NAME           READY     STATUS    RESTARTS   AGE
kube100-site   2/2       Running   0          1m
注: Pod创建过程中如果出现错误,可以使用kubectl describe 进行排查。

各字段含义:
    NAME: Pod的名称
    READY: Pod的准备状况,右边的数字表示Pod包含的容器总数目,左边的数字表示准备就绪的容器数目。
    STATUS: Pod的状态。
    RESTARTS: Pod的重启次数
    AGE: Pod的运行时间。

pod的准备状况指的是Pod是否准备就绪以接收请求,Pod的准备状况取决于容器,即所有容器都准备就绪了,Pod才准备就绪。这时候kubernetes的代理服务才会添加Pod作为分发后端,而一旦Pod的准备状况变为false(至少一个容器的准备状况为false),kubernetes会将Pod从代理服务的分发后端移除,即不会分发请求给该Pod。

一个pod刚被创建的时候是不会被调度的,因为没有任何节点被选择用来运行这个pod。调度的过程发生在创建完成之后,但是这个过程一般很快,所以你通常看不到pod是处于unscheduler状态的除非创建的过程遇到了问题。

pod被调度之后,分配到指定的节点上运行,这时候,如果该节点没有所需要的image,那么将会自动从默认的Docker Hub上pull指定的image,一切就绪之后,看到pod是处于running状态了:

# kubectl get pods
NAME                         READY     STATUS    RESTARTS   AGE
my-nginx-379829228-2zjv3     1/1       Running   0          1h
my-nginx-379829228-mm8f8     1/1       Running   0          1h
查看pods所在的运行节点:
# kubectl get pods -o wide
查看pods定义的详细信息:
# kubectl get pods -o yaml
# kubectl get pod nginx-8v3cg --output yaml

kubectl get支持以Go Template方式过滤指定的信息,比如查询Pod的运行状态
# kubectl get pods busybox --output=go-template --template={{.status.phase}}
Running

查看pod输出:
你可能会有想了解在pod中执行命令的输出是什么,和Docker logs命令一样,kubectl logs将会显示这些输出:

kubectl logs pod名称

hello world

查看kubectl describe 支持查询Pod的状态和生命周期事件:

[root@k8s-master ~]# kubectl describe   pod  busybox
Name:       busybox
Namespace:  default
Node:       k8s-node-1/116.196.105.133
Start Time: Thu, 22 Mar 2018 09:51:35 +0800
Labels:     name=busybox
        role=master
Status:     Pending
IP:     
Controllers:    <none>
Containers:
  busybox:
    Container ID:   
    Image:      docker.io/busybox
    Image ID:       
    Port:       
    Command:
      sleep
      360000
    State:          Waiting
      Reason:           ContainerCreating
    Ready:          False
    Restart Count:      0
    Volume Mounts:      <none>
    Environment Variables:  <none>
Conditions:
  Type      Status
  Initialized   True 
  Ready     False 
  PodScheduled  True 
No volumes.
QoS Class:  BestEffort
Tolerations:    <none>
Events:
  FirstSeen LastSeen    Count   From            SubObjectPath   Type        Reason      Message
  --------- --------    -----   ----            -------------   --------    ------      -------
  7m        7m      1   {default-scheduler }            Normal      Scheduled   Successfully assigne
d busybox to k8s-node-1  7m     1m      6   {kubelet k8s-node-1}            Warning     FailedSync  Error syncing pod, s
kipping: failed to "StartContainer" for "POD" with ErrImagePull: "image pull failed for registry.access.redhat.com/rhel7/pod-infrastructure:latest, this may be because there are no credentials on this request.  details: (open /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt: no such file or directory)"
  6m    13s 27  {kubelet k8s-node-1}        Warning FailedSync  Error syncing pod, skipping: failed to "StartContain
er" for "POD" with ImagePullBackOff: "Back-off pulling image \"registry.access.redhat.com/rhel7/pod-infrastructure:latest\""

各字段含义:
    Name: Pod的名称
    Namespace: Pod的Namespace。
    Image(s): Pod使用的镜像
    Node: Pod所在的Node。
    Start Time: Pod的起始时间
    Labels: Pod的Label。
    Status: Pod的状态。
    Reason: Pod处于当前状态的原因。
    Message: Pod处于当前状态的信息。
    IP: Pod的PodIP
    Replication Controllers: Pod对应的Replication Controller。

    Containers:Pod中容器的信息

            Container ID: 容器的ID
            Image: 容器的镜像
            Image ID:镜像的ID
            State: 容器的状态
            Ready: 容器的准备状况(true表示准备就绪)。
            Restart Count: 容器的重启次数统计
            Environment Variables: 容器的环境变量
            Conditions: Pod的条件,包含Pod准备状况(true表示准备就绪)
            Volumes: Pod的数据卷
            Events: 与Pod相关的事件列表
进入Pod对应的容器内部 
[root@k8s-master /]# kubectl exec -it myweb-76h6w /bin/bash

删除pod:

    # kubectl delete pod pod名1 pod名2   //单个或多个删除
    # kubectl delete pod --all   //批量删除
    例:
    [root@k8s-master /]# kubectl  delete pod hello-world
    pod "hello-world" deleted

重新启动基于yaml文件的应用

kubectl delete -f XXX.yaml
kubectl apply -f XXX.yaml

常用命令

kubectl get pods
kubectl get pods -o wide
/opt/kubernetes/bin/kubectl get svc
/opt/kubernetes/bin/kubectl get cs
/opt/kubernetes/bin/kubectl get pods
kubectl apply -f pod.yaml
kubectl logs pod名称
kubectl describe   pod  busybox
kubectl delete pod pod名1 pod名2
kubectl delete -f XXX.yaml
kubectl apply -f XXX.yaml
kubectl exec -it myweb-76h6w /bin/bash

作者:朱溪江