kubernetes之手动部署k8s 1.14.1高可用集群

1. 架构信息

系统版本：CentOS 7.6
内核：3.10.0-957.el7.x86_64
Kubernetes: v1.14.1
Docker-ce: 18.09.5
推荐硬件配置：4核8G

Keepalived保证apiserever服务器的IP高可用
Haproxy实现apiserver的负载均衡 

2. 节点信息

目前测试为 6 台虚拟机，etcd采用 rpm 安装、kubernetes 使用二进制安装，使用 systemd 来做管理，网络组件采用 flannel，Master 实现了 HA， 集群开启 RBAC；master 不负载 pod，在分发证书等阶段将在另外一台主机上执行，该主机对集群内所有节点配置了 ssh 秘钥登录，基本环境如下

hostname	ip	组件	内存	cpu
node-01	172.19.8.111	kube-apiserver、kube-controller-manager、etcd、haproxy、keepalived	8G	4c
node-02	172.19.8.112	kube-apiserver、kube-controller-manager、etcd、haproxy、keepalived	8G	4c
node-03	172.19.8.113	kube-apiserver、kube-controller-manager、etcd	8G	4c
node-04	172.19.8.114	node	8G	4c
node-05	172.19.8.115	node	8G	4c
node-06	172.19.8.116	node	8G	4c
VIP	172.19.8.250

3.1  关闭防火墙和selinux3. 部署前准备工作

[root@node-01 ~]# sed -ri 's#(SELINUX=).*#\1disabled#' /etc/selinux/config

[root@node-01 ~]# setenforce 0

[root@node-01 ~]# systemctl disable firewalld

[root@node-01 ~]# systemctl stop firewalld

3.2 关闭swap

[root@node-01 ~]# swapoff -a
注：修改/etc/fstab，注销swap相关信息

3.3 添加host记录

[root@node-01 ~]# cat >>/etc/hosts<<EOF
172.19.8.111 node-01
172.19.8.112 node-02
172.19.8.113 node-03
172.19.8.114 node-04
172.19.8.115 node-05
172.19.8.116 node-06
EOF

3.4 打通ssh， node-01免密登录其他服务器

[root@node-01 ~]# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:uckCmzy46SfU6Lq9jRbugn0U8vQsr5H+PtfGBsvrfCA root@node-01
The key's randomart image is:
+---[RSA 2048]----+
|                 |
|                 |
|                 |
|  . o    .       |
|   *.+  S        |
|  +o==E.oo       |
|.=.oBo.o+*       |
|o.**oooo+ *      |
|oBO=++o++=       |
+----[SHA256]-----+

分发node-01公钥，用于免密登录其他服务器

[root@node-01 ~]# for n in `seq -w 01 06`;do ssh-copy-id node-$n;done

3.5  配置内核参数，需要重启服务器，否则后面初始化的时候会报错。

cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
vm.swappiness=0
EOF

sysctl --system

报错处理,没有桥接网络导致，需要安装docker，并启动后才会出现桥接网络

[root@node-01 ~]# sysctl -p /etc/sysctl.d/k8s.conf
net.ipv4.ip_forward = 1
sysctl: cannot stat /proc/sys/net/bridge/bridge-nf-call-ip6tables: 没有那个文件或目录
sysctl: cannot stat /proc/sys/net/bridge/bridge-nf-call-iptables: 没有那个文件或目录

3.6 如果kube-proxy使用ipvs模式，需要加载ipvs模块

cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF
chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep -e ip_vs -e nf_conntrack_ipv4

3.7  添加yum源

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
exclude=kube*
EOF

考虑到国内无法拉取google源，可以使用阿里云源

$ cat << EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

wget http://mirrors.aliyun.com/repo/Centos-7.repo -O /etc/yum.repos.d/CentOS-Base.repo
wget http://mirrors.aliyun.com/repo/epel-7.repo -O /etc/yum.repos.d/epel.repo

以上部署需要在每个节点执行。

4.  部署keepalived和haproxy

4.1 在node-01和node-02上面安装keepalived和haproxy

$ yum install -y keepalived haproxy

4.2 配置keepalived

node-01 配置信息

[root@node-01 ~]# cat /etc/keepalived/keepalived.conf
! Configuratile for keepalived
global_defs {
 notification_email {
[e-mail]
      }
 notification_email_from [e-mail]
 smtp_server 127.0.0.1
 smtp_connect_timeout 30
 router_id node-01
}

vrrp_script check_apiserver {
     script "/workspace/crontab/check_apiserver"
     interval 5
     weight -20
     fall 3
     rise 1
     }

vrrp_instance VIP_250 {
    state MASTER
    interface eth0
    virtual_router_id 250
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 890iop
    }
    track_script {
      check_apiserver
     }
    virtual_ipaddress {
        172.19.8.250
    }
}

检查脚本配置

$ cat /workspace/crontab/check_apiserver
#!/bin/bash
curl 127.0.0.1:8080 &>/dev/null
if [ $? -eq 0 ];then
    exit 0
else
    #systemctl stop keepalived
    exit 1
fi
$ chmod 755 /workspace/crontab/check_apiserver

node-02 配置

[root@node-02 ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
 notification_email {
[e-mail]
      }
 notification_email_from [e-mail]
 smtp_server 127.0.0.1
 smtp_connect_timeout 30
 router_id node-02
}

vrrp_instance VI_250 {
    state BACKUP
    interface eth0
    virtual_router_id 250
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 890iop
    }
    virtual_ipaddress {
    172.19.8.250
    }
}

4.3 配置haproxy

node-01和node-02的haproxy配置是一样的。此处我们监听的是172.19.8.250的8443端口，因为haproxy是和k8s apiserver是部署在同一台服务器上，都用6443会冲突。 

[root@node-01 ~]# cat /etc/haproxy/haproxy.cfg
global
        chroot  /var/lib/haproxy
        daemon
        group haproxy
        user haproxy
#        log warning
        pidfile /var/lib/haproxy.pid
        maxconn 20000
        spread-checks 3
        nbproc 8

defaults
        log     global
        mode    tcp
        retries 3
        option redispatch

listen https-apiserver
        bind 0.0.0.0:8443
        mode tcp
        balance roundrobin
        timeout server 900s
        timeout connect 15s

        server apiserver01 172.19.8.111:6443 check port 6443 inter 5000 fall 5
        server apiserver02 172.19.8.112:6443 check port 6443 inter 5000 fall 5
        server apiserver03 172.19.8.113:6443 check port 6443 inter 5000 fall 5

4.4 启动服务

systemctl enable keepalived && systemctl start keepalived
systemctl enable haproxy && systemctl start haproxy 

5  配置证书

创建集群 CA 与 Certificates

5.1 证书介绍

在这部分，将会需要产生 client 与 server 的各组件 certificates，并且替 Kubernetes admin user 产生 client 证书。由于 Etcd 和 Kubernetes 全部采用 TLS 通讯，所以先要生成 TLS 证书，证书生成工具采用 cfssl，生成证书时可在任一节点完成，这里在宿主机执行，证书列表如下

证书名称	配置文件	用途
etcd-root-ca.pem	etcd-root-ca-csr.json	etcd 根 CA 证书
etcd.pem	etcd-gencert.json、etcd-csr.json	etcd 集群证书
k8s-root-ca.pem	k8s-root-ca-csr.json	k8s 根 CA 证书
kube-proxy.pem	k8s-gencert.json、kube-proxy-csr.json	kube-proxy 使用的证书
admin.pem	k8s-gencert.json、admin-csr.json	kubectl 使用的证书
kubernetes.pem	k8s-gencert.json、kubernetes-csr.json	kube-apiserver 使用的证书

5.2 cfssl 工具安装

首先下载 cfssl，并给予可执行权限，然后扔到 PATH 目录下

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

5.3 生成etcd证书

注意，所有证书生成只需要在任意一台主机上生成一遍即可，我这里在 node-01 上操作的。

etcd-csr.json   #产生 kube-apiserver certificate 证书

cat <<EOF>> etcd-csr.json
{
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "O": "etcd",
      "OU": "etcd Security",
      "L": "Beijing",
      "ST": "Beijing",
      "C": "CN"
    }
  ],
  "CN": "etcd",
  "hosts": [
    "127.0.0.1",
    "localhost",
    "172.19.8.111",
    "172.19.8.112",
    "172.19.8.113"
  ]
}
EOF

etcd-gencert.json    #产生 CA 密钥

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

etcd-root-ca-csr.json     #产生 CA 密钥

cat <<EOF>> etcd-root-ca-csr.json
{
  "key": {
    "algo": "rsa",
    "size": 4096
  },
  "names": [
    {
      "O": "etcd",
      "OU": "etcd Security",
      "L": "Beijing",
      "ST": "Beijing",
      "C": "CN"
    }
  ],
  "CN": "etcd-root-ca"
}
EOF

最后生成证书

cfssl gencert --initca=true etcd-root-ca-csr.json | cfssljson --bare etcd-root-ca
cfssl gencert --ca etcd-root-ca.pem --ca-key etcd-root-ca-key.pem --config etcd-gencert.json etcd-csr.json | cfssljson --bare etcd

完成后删除不必要文件：

rm -rf *.json

确认/etc/etcd/ssl有以下文件：

etcd.csr  etcd-key.pem  etcd.pem  etcd-root-ca.csr  etcd-root-ca-key.pem  etcd-root-ca.pe

5.4 生成k8s证书需要借助kubectl，下面安装k8s会介绍。

6 安装etcd

6.1 在node-01、node-02、node-03节点安装etcd

$ yum -y install etcd

6.2  所有节点部署证书

$ mkdir /etc/etcd/ssl
$ scp *.pem /etc/etcd/ssl
$ chown -R etcd:etcd /etc/etcd/ssl
$ chmod -R 644 /etc/etcd/ssl/*
$ chmod 755 /etc/etcd/ssl

6.3  修改etcd数据目录权限

$ chown -R etcd:etcd /var/lib/etcd /etc/etcd

6.4 然后修改配置如下(其他两个节点类似，只需要改监听地址和 Etcd Name 即可)

[root@node-01 kubernetes]# cat /etc/etcd/etcd.conf
#[Member]
#ETCD_CORS=""
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
#ETCD_WAL_DIR=""
ETCD_LISTEN_PEER_URLS="https://172.19.8.111:2380"
ETCD_LISTEN_CLIENT_URLS="https://172.19.8.111:2379"
#ETCD_MAX_SNAPSHOTS="5"
#ETCD_MAX_WALS="5"
ETCD_NAME="etcd1"
#ETCD_SNAPSHOT_COUNT="100000"
#ETCD_HEARTBEAT_INTERVAL="100"
#ETCD_ELECTION_TIMEOUT="1000"
#ETCD_QUOTA_BACKEND_BYTES="0"
#ETCD_MAX_REQUEST_BYTES="1572864"
#ETCD_GRPC_KEEPALIVE_MIN_TIME="5s"
#ETCD_GRPC_KEEPALIVE_INTERVAL="2h0m0s"
#ETCD_GRPC_KEEPALIVE_TIMEOUT="20s"
#
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://172.19.8.111:2380"
ETCD_ADVERTISE_CLIENT_URLS="https://172.19.8.111:2379"
#ETCD_DISCOVERY=""
#ETCD_DISCOVERY_FALLBACK="proxy"
#ETCD_DISCOVERY_PROXY=""
#ETCD_DISCOVERY_SRV=""
ETCD_INITIAL_CLUSTER="etcd1=https://172.19.8.111:2380,etcd2=https://172.19.8.112:2380,etcd3=https://172.19.8.113:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
#ETCD_STRICT_RECONFIG_CHECK="true"
#ETCD_ENABLE_V2="true"
#
#[Proxy]
#ETCD_PROXY="off"
#ETCD_PROXY_FAILURE_WAIT="5000"
#ETCD_PROXY_REFRESH_INTERVAL="30000"
#ETCD_PROXY_DIAL_TIMEOUT="1000"
#ETCD_PROXY_WRITE_TIMEOUT="5000"
#ETCD_PROXY_READ_TIMEOUT="0"
#
#[Security]
#ETCD_CERT_FILE=""
#ETCD_KEY_FILE=""
#ETCD_CLIENT_CERT_AUTH="false"
#ETCD_TRUSTED_CA_FILE=""
#ETCD_AUTO_TLS="false"
#ETCD_PEER_CERT_FILE=""
#ETCD_PEER_KEY_FILE=""
#ETCD_PEER_CLIENT_CERT_AUTH="false"
#ETCD_PEER_TRUSTED_CA_FILE=""
#ETCD_PEER_AUTO_TLS="false"
ETCD_CERT_FILE="/etc/etcd/ssl/etcd.pem"
ETCD_KEY_FILE="/etc/etcd/ssl/etcd-key.pem"
ETCD_CLIENT_CERT_AUTH="true"
ETCD_TRUSTED_CA_FILE="/etc/etcd/ssl/etcd-root-ca.pem"
ETCD_AUTO_TLS="true"
ETCD_PEER_CERT_FILE="/etc/etcd/ssl/etcd.pem"
ETCD_PEER_KEY_FILE="/etc/etcd/ssl/etcd-key.pem"
ETCD_PEER_CLIENT_CERT_AUTH="true"
ETCD_PEER_TRUSTED_CA_FILE="/etc/etcd/ssl/etcd-root-ca.pem"
ETCD_PEER_AUTO_TLS="true"
#
#[Logging]
#ETCD_DEBUG="false"
#ETCD_LOG_PACKAGE_LEVELS=""
#ETCD_LOG_OUTPUT="default"
#
#[Unsafe]
#ETCD_FORCE_NEW_CLUSTER="false"
#
#[Version]
#ETCD_VERSION="false"
#ETCD_AUTO_COMPACTION_RETENTION="0"
#
#[Profiling]
#ETCD_ENABLE_PPROF="false"
#ETCD_METRICS="basic"
#
#[Auth]
#ETCD_AUTH_TOKEN="simple"

6.5  最后启动集群并测试如下

$ systemctl daemon-reload
$ systemctl start etcd
$ systemctl enable etcd

[root@node-01 ~]# etcdctl --ca-file=/etc/etcd/ssl/etcd-root-ca.pem --cert-file=/etc/etcd/ssl/etcd.pem --key-file=/etc/etcd/ssl/etcd-key.pem --endpoints=https://172.19.8.111:2379,https://172.19.8.112:2379,https://172.19.8.113:2379 cluster-health
member 20eaf623ac3b75e0 is healthy: got healthy result from https://172.19.8.112:2379
member 49a1ffa1fb4e8c74 is healthy: got healthy result from https://172.19.8.111:2379
member d6afeec04f7054b4 is healthy: got healthy result from https://172.19.8.113:2379
cluster is healthy

如果检查失败，通过日志排查，重点检查etcd节点配置信息。

7 安装kubernetes

7.1 生成kubernetes证书

下载软件包

# master
wget https://dl.k8s.io/v1.14.0/kubernetes-server-linux-amd64.tar.gz
cp kubernetes/server/bin/{kube-apiserver,kube-scheduler,kube-controller-manager} /bin/

# node
https://dl.k8s.io/v1.14.0/kubernetes-node-linux-amd64.tar.gz

# 将下载的包解压，然后将 server/bin/ 和 node/bin/ 中的执行文件拷贝到各自的/bin下

在这部分，将会需要生成 client 与 server 的各组件 certificates，并且替 Kubernetes admin user 生成 client 证书。

#!/bin/bash
# Deploy the master node.
KUBE_SSL=/etc/kubernetes/ssl
mkdir -p $KUBE_SSL

# Create CA.
cat>$KUBE_SSL/ca-config.json<<EOF
{
  "signing": {
    "default": {
      "expiry": "87600h"
    },
    "profiles": {
      "kubernetes": {
         "expiry": "87600h",
         "usages": [
            "signing",
            "key encipherment",
            "server auth",
            "client auth"
        ]
      }
    }
  }
}
EOF
cat>$KUBE_SSL/ca-csr.json<<EOF
{
    "CN": "kubernetes",
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "L": "Beijing",
            "ST": "Beijing",
            "O": "k8s",
            "OU": "IMG"
        }
    ]
}
EOF

# “10.254.0.1"  注意此处需要添加指定，与cluster-cidr同网段，例如192.168.0.1

cat>$KUBE_SSL/server-csr.json<<EOF
{
    "CN": "kubernetes",
    "hosts": [
      "10.254.0.1",    #注意此处需要添加指定，与cluster-cidr同网段，例如192.168.0.1
      "127.0.0.1",
"172.19.8.111",
      "172.19.8.112",
      "172.19.8.113",
      "172.19.8.114",
      "172.19.8.115",
      "172.19.8.116",
      "172.19.8.250",
"localhost",
      "apiclient",
      "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": "IMG"
        }
    ]
}
EOF
cd $KUBE_SSL
cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes server-csr.json | cfssljson -bare server

# Create kube-proxy CA.
cat>$KUBE_SSL/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": "IMG"
    }
  ]
}
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
ls *.pem
cd ~

每个节点需要关闭 swap。

Kubernetes 1.8 开始要求关闭系统的 Swap，如果不关闭，默认配置下 kubelet 将无法启动。可以通过 kubelet 的启动参数–fail-swap-on=false 更改这个限制。

生成token

# Create a token file.
cat>/etc/kubernetes/token.csv<<EOF
$(head -c 16 /dev/urandom | od -An -t x | tr -d ' '),kubelet-bootstrap,10001,"system:kubelet-bootstrap"
EOF

7.2 node-01安装apiserver

[root@node-01 kubernetes]# cat apiserver.conf
#
KUBE_APISERVER_OPTS="—logtostderr=false \
--etcd-servers=https://172.19.8.111:2379,https://172.19.8.112:2379,https://172.19.8.113:2379 \
--v=4 \
--bind-address=172.19.8.111 \
--secure-port=6443 \
--advertise-address=172.19.8.111 \
--allow-privileged=true \
--service-cluster-ip-range=10.254.0.0/16 \
--enable-admission-plugins=NamespaceLifecycle,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota,NodeRestriction \
--authorization-mode=RBAC,Node \
--enable-bootstrap-token-auth \
--token-auth-file=/etc/kubernetes/token.csv \
--service-node-port-range=30000-50000 \
--tls-cert-file=/etc/kubernetes/ssl/server.pem  \
--tls-private-key-file=/etc/kubernetes/ssl/server-key.pem \
--client-ca-file=/etc/kubernetes/ssl/ca.pem \
--service-account-key-file=/etc/kubernetes/ssl/ca-key.pem \
--etcd-cafile=/etc/etcd/ssl/etcd-root-ca.pem \
--etcd-certfile=/etc/etcd/ssl/etcd.pem \
--etcd-keyfile=/etc/etcd/ssl/etcd-key.pem"

配置启动脚本

# Create the kube-apiserver service.
$ cat /usr/lib/systemd/system/kube-apiserver.service
[Unit]
Description=Kubernetes API Server
Documentation=https://github.com/kubernetes/kubernetes
After=etcd.service
Wants=etcd.service

[Service]
EnvironmentFile=-/etc/kubernetes/apiserver.conf
ExecStart=/bin/kube-apiserver $KUBE_APISERVER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target

$ systemctl daemon-reload
$ systemctl enable kube-apiserver.service --now
$ systemctl status kube-apiserver.service

7.3  node-01 安装api-controller-manager

$ cat /etc/kubernetes/kube-controller-manager.conf

KUBE_CONTROLLER_MANAGER_OPTS="—logtostderr=false \
--v=4 \
--master=127.0.0.1:8080 \
--leader-elect=true \
--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  \
--root-ca-file=/etc/kubernetes/ssl/ca.pem \
--service-account-private-key-file=/etc/kubernetes/ssl/ca-key.pem"

配置启动脚本

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

[Service]
EnvironmentFile=-/etc/kubernetes/kube-controller-manager.conf
ExecStart=/bin/kube-controller-manager $KUBE_CONTROLLER_MANAGER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target

-------

$ systemctl daemon-reload
$ systemctl enable kube-controller-manager.service --now
$ systemctl status kube-controller-manager.service

7.4  node-01安装schedule

[root@node-01 kubernetes]# cat /etc/kubernetes/kube-scheduler.conf
KUBE_SCHEDULER_OPTS="—logtostderr=false \
--v=4 \
--master=127.0.0.1:8080 \
--leader-elect"

配置启动脚本

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

[Service]
EnvironmentFile=-/etc/kubernetes/kube-scheduler.conf
ExecStart=/bin/kube-scheduler $KUBE_SCHEDULER_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target

——————

$ systemctl daemon-reload
$ systemctl enable kube-scheduler.service --now
$ systemctl status kube-scheduler.service

检查节点状态

[root@node-01 ~]# kubectl get cs
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"}

node-02、node-03 做上述相同配置，需要修改ip地址。

8 部署node节点

8.1  创建bootstrap和kube-proxy的kubeconfig文件

在master 节点上执行下面的脚本创建bootstrap.kubeconfig和kube-proxy.kubeconfig文件

由于通过手动创建 CA 方式太过繁杂，只适合少量机器，因为每次签证时都需要绑定 Node IP，随机器增加会带来很多困扰，因此这边使用 TLS Bootstrapping 方式进行授权，由 apiserver 自动给符合条件的 Node 发送证书来授权加入集群。

主要做法是 kubelet 启动时，向 kube-apiserver 传送 TLS Bootstrapping 请求，而 kube-apiserver 验证 kubelet 请求的 token 是否与设定的一样，若一样就自动产生 kubelet 证书与密钥。具体作法可以参考 TLS bootstrapping。

通过脚本创建kubeconfig文件

$ cat nodeprepare.sh
#!/bin/bash

BOOTSTRAP_TOKEN=$(awk -F "," '{print $1}' /etc/kubernetes/token.csv)
KUBE_SSL=/etc/kubernetes/ssl/
KUBE_APISERVER="https://172.19.8.250:8443"

cd $KUBE_SSL
# Set cluster parameters.
kubectl config set-cluster kubernetes \
  --certificate-authority=./ca.pem \
  --embed-certs=true \
  --server=${KUBE_APISERVER} \
  --kubeconfig=/etc/kubernetes/bootstrap.kubeconfig

# Set client parameters.
kubectl config set-credentials kubelet-bootstrap \
  --token=${BOOTSTRAP_TOKEN} \
  --kubeconfig=/etc/kubernetes/bootstrap.kubeconfig

# Set context parameters.
kubectl config set-context default \
  --cluster=kubernetes \
  --user=kubelet-bootstrap \
  --kubeconfig=/etc/kubernetes/bootstrap.kubeconfig

# Set context.
kubectl config use-context default --kubeconfig=/etc/kubernetes/bootstrap.kubeconfig

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

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

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

kubectl config use-context default --kubeconfig=/etc/kubernetes/kube-proxy.kubeconfig
cd ~

# Bind kubelet-bootstrap user to system cluster roles.
kubectl create clusterrolebinding kubelet-bootstrap \
  --clusterrole=system:node-bootstrapper \
  --user=kubelet-bootstrap

8.2  配置kube-proxy和kubelet

将master节点证书、token.csv和bootstrap.kubeconfig,kube-proxy.kubeconfig拷贝到node节点 .

8.2.1 以node-04为例,配置kube-proxy节点

[root@node-04 kubernetes]# cat /etc/kubernetes/kube-proxy.conf
KUBE_PROXY_OPTS="--logtostderr=false \
--v=4 \
--hostname-override=172.19.8.114 \
--cluster-cidr=10.254.0.0/16 \
--kubeconfig=/etc/kubernetes/kube-proxy.kubeconfig"

配置启动脚本

[root@node-04 kubernetes]# cat /usr/lib/systemd/system/kube-proxy.service
[Unit]
Description=Kubernetes Proxy
After=network.target

[Service]
EnvironmentFile=-/etc/kubernetes/kube-proxy.conf
ExecStart=/bin/kube-proxy $KUBE_PROXY_OPTS
Restart=on-failure

[Install]
WantedBy=multi-user.target

启动

[root@node-04 kubernetes]# systemctl daemon-reload
[root@node-04 kubernetes]# systemctl start kube-proxy.service
[root@node-04 kubernetes]# systemctl enable kube-proxy.service
[root@node-04 kubernetes]# systemctl status kube-proxy.service -l

8.2.2  配置kubelet

[root@node-04 kubernetes]# cat /etc/kubernetes/kubelet.yaml
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
address: 172.19.8.114
port: 10250
readOnlyPort: 10255
cgroupDriver: cgroupfs
clusterDNS: ["10.254.0.2"]
clusterDomain: cluster.local.
failSwapOn: false
authentication:
  anonymous:
    enabled: true

[root@node-04 kubernetes]# cat /etc/kubernetes/kubelet.conf
KUBELET_OPTS="--logtostderr=false \
--v=4 \
--hostname-override=172.19.8.114 \
--kubeconfig=/etc/kubernetes/kubelet.kubeconfig \
--bootstrap-kubeconfig=/etc/kubernetes/bootstrap.kubeconfig \
--config=/etc/kubernetes/kubelet.yaml \
--cert-dir=/etc/kubernetes/ssl \
--pod-infra-container-image=gcr.io/google-containers/pause-amd64:3.0"

配置启动文件

[root@node-04 kubernetes]# cat /usr/lib/systemd/system/kubelet.service
[Unit]
Description=Kubernetes Kubelet
After=docker.service
Requires=docker.service

[Service]
EnvironmentFile=/etc/kubernetes/kubelet.conf
ExecStart=/bin/kubelet $KUBELET_OPTS
Restart=on-failure
KillMode=process

[Install]
WantedBy=multi-user.target

启动

[root@node-04 kubernetes]# systemctl daemon-reload
[root@node-04 kubernetes]# systemctl enable kubelet.service --now
[root@node-04 kubernetes]# systemctl status kubelet.service -l

node-05 node-06 做相同配置，注意修改IP地址。

kubelet启动后，会向apiserver申请注册，此时apiserver需要同意申请，node才能加入进去。

[root@node-01 ~]# kubectl get csr
NAME                                                   AGE   REQUESTOR           CONDITION
node-csr-K_cecykFJ_g1cAJf5DTJ_EVFUH3W9QgfulMA-TbFoMo   45s   kubelet-bootstrap   Pending

[root@node-01 ~]# kubectl certificate approve node-csr-K_cecykFJ_g1cAJf5DTJ_EVFUH3W9QgfulMA-TbFoMo
certificatesigningrequest.certificates.k8s.io/node-csr-K_cecykFJ_g1cAJf5DTJ_EVFUH3W9QgfulMA-TbFoMo approved

[root@node-01 ~]# kubectl get node
NAME           STATUS   ROLES    AGE   VERSION
172.19.8.114   Ready    <none>   12s   v1.14.1

此时node已经加入。

9 所有节点部署flannel网络插件

9.1 检查etcd节点状态

[root@node-01 ~]# etcdctl --ca-file=/etc/etcd/ssl/etcd-root-ca.pem --cert-file=/etc/etcd/ssl/etcd.pem --key-file=/etc/etcd/ssl/etcd-key.pem --endpoints=https://172.19.8.111:2379,https://172.19.8.112:2379,https://172.19.8.113:2379 cluster-health
member 20eaf623ac3b75e0 is healthy: got healthy result from https://172.19.8.112:2379
member 49a1ffa1fb4e8c74 is healthy: got healthy result from https://172.19.8.111:2379
member d6afeec04f7054b4 is healthy: got healthy result from https://172.19.8.113:2379
cluster is healthy

9.2 在etcd中创建flannel网络

export ETCDCTL_API=2
etcdctl --ca-file=/etc/etcd/ssl/etcd-root-ca.pem --cert-file=/etc/etcd/ssl/etcd.pem --key-file=/etc/etcd/ssl/etcd-key.pem --endpoints=https://172.19.8.111:2379,https://172.19.8.112:2379,https://172.19.8.113:2379 set /coreos.com/network/config  '{ "Network": "10.244.0.0/16", "Backend": {"Type": "vxlan"}}'

之前使用etcd api3创建flannel创建网络，在flannel启动时一直报错，报错信息如下，改为api2，问题解决

# Writing into a predetermined subnetwork.Master节点设置
#注意 一开始默认使用ETCDCTL_API=3，发现flannel连接etcd读取下列信息失败，一直保报错 Couldn't fetch network config: 100: Key not found

9.3  下载flannel

# https://github.com/coreos/flannel/releases
wget https://github.com/coreos/flannel/releases/download/v0.11.0/flannel-v0.11.0-linux-amd64.tar.gz

# 软件包包含flanneld 和 mk-docker-opts.sh
mv {flanneld,mk-docker-opts.sh} /bin/

9.4  复制etcd证书到各node节点,目录为/etc/etcd/ssl

[root@node-04 ~]# cd /etc/etcd/ssl/
[root@node-04 ssl]# ls
etcd-key.pem  etcd.pem  etcd-root-ca-key.pem  etcd-root-ca.pem

9.5 配置flannel

[root@node-04 kubernetes]# cat /etc/kubernetes/flannel.conf
FLANNEL_ETCD_KEY="/coreos.com/network"
FLANNEL_OPTIONS="--etcd-endpoints=https://172.19.8.111:2379,https://172.19.8.112:2379,https://172.19.8.113:2379 -etcd-cafile=/etc/etcd/ssl/etcd-root-ca.pem -etcd-certfile=/etc/etcd/ssl/etcd.pem -etcd-keyfile=/etc/etcd/ssl/etcd-key.pem"

配置启动文件

[root@node-04 kubernetes]# cat /usr/lib/systemd/system/flanneld.service
[Unit]
Description=Flanneld overlay address etcd agent
After=network-online.target network.target
Before=docker.service

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

[Install]
WantedBy=multi-user.target

9.6 修改docker启动文件

# Modify the docker service.

cat /usr/lib/systemd/system/docker.service
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
BindsTo=containerd.service
After=network-online.target firewalld.service containerd.service
Wants=network-online.target
Requires=docker.socket

[Service]
Type=notify
EnvironmentFile=/run/flannel/subnet.env
ExecStart=/usr/bin/dockerd $DOCKER_NETWORK_OPTIONS
ExecReload=/bin/kill -s HUP $MAINPID
TimeoutSec=0
RestartSec=2
Restart=always
StartLimitBurst=3
StartLimitInterval=60s
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
TasksMax=infinity
Delegate=yes
KillMode=process

[Install]
WantedBy=multi-user.target

启动

# Start or restart related services.
systemctl daemon-reload
systemctl enable flanneld --now
systemctl restart docker
systemctl status flanneld
systemctl status docker

检查创建的网络

[root@node-04 kubernetes]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether fa:d7:b7:9e:55:00 brd ff:ff:ff:ff:ff:ff
    inet 172.19.8.114/24 brd 172.19.8.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
3: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default
    link/ether 02:42:88:36:c8:89 brd ff:ff:ff:ff:ff:ff
    inet 10.244.82.1/24 brd 10.244.82.255 scope global docker0
       valid_lft forever preferred_lft forever
4: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN group default
    link/ether da:b3:f5:69:bf:de brd ff:ff:ff:ff:ff:ff
    inet 10.244.82.0/32 scope global flannel.1
       valid_lft forever preferred_lft forever

[root@node-04 ~]# cat /run/flannel/subnet.env
DOCKER_OPT_BIP="--bip=10.244.16.1/24"
DOCKER_OPT_IPMASQ="--ip-masq=false"
DOCKER_OPT_MTU="--mtu=1450"
DOCKER_NETWORK_OPTIONS=" --bip=10.244.16.1/24 --ip-masq=false --mtu=1450"

10 部署nginx小战一下

[root@node-01 ~]# kubectl apply -f nginx-dep.yml

[root@node-01 ~]# kubectl get pods
NAME                               READY   STATUS              RESTARTS   AGE
nginx-deployment-6dd86d77d-txhmg   0/1     ContainerCreating   0          11s
nginx-deployment-6dd86d77d-vc4mx   0/1     ContainerCreating   0          11s

[root@node-01 ~]# kubectl describe pod nginx-deployment-6dd86d77d-txhmg     # 检查为什么pod启动失败

  Warning  FailedCreatePodSandBox  50s    kubelet, 172.19.8.116  Failed create pod sandbox: rpc error: code = Unknown desc = failed pulling image "img.cn/google-containers/pause-amd64:3.0": Error response from daemon: 
Get https://img.cn/v2/: net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

# 原因：kubelet.conf 配置的 --pod-infra-container-image 镜像地址拉取失败

11 配置coredns

11.1 添加anonymous认证

kubectl create clusterrolebinding cluster-system-anonymous --clusterrole=cluster-admin --user=system:anonymous

11.2 配置coredns

[root@node-01 ~]# cat coredns.yml
apiVersion: v1
kind: ServiceAccount
metadata:
  name: coredns
  namespace: kube-system
  labels:
      kubernetes.io/cluster-service: "true"
      addonmanager.kubernetes.io/mode: Reconcile
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
    addonmanager.kubernetes.io/mode: Reconcile
  name: system:coredns
rules:
- apiGroups:
  - ""
  resources:
  - endpoints
  - services
  - pods
  - namespaces
  verbs:
  - list
  - watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
    addonmanager.kubernetes.io/mode: EnsureExists
  name: system:coredns
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:coredns
subjects:
- kind: ServiceAccount
  name: coredns
  namespace: kube-system
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: coredns
  namespace: kube-system
  labels:
      addonmanager.kubernetes.io/mode: EnsureExists
data:
  Corefile: |
    .:53 {
        errors
        health
        kubernetes cluster.local. in-addr.arpa ip6.arpa {
            pods insecure
            upstream
            fallthrough in-addr.arpa ip6.arpa
        }
        prometheus :9153
        forward . /etc/resolv.conf
        cache 30
    }
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: coredns
  namespace: kube-system
  labels:
    k8s-app: coredns
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    kubernetes.io/name: "CoreDNS"
spec:
  replicas: 2
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 1
  selector:
    matchLabels:
      k8s-app: coredns
  template:
    metadata:
      labels:
        k8s-app: coredns
    spec:
      serviceAccountName: coredns
      tolerations:
        - key: node-role.kubernetes.io/master
          effect: NoSchedule
        - key: "CriticalAddonsOnly"
          operator: "Exists"
      containers:
      - name: coredns
        image: coredns/coredns:1.5.0
        imagePullPolicy: IfNotPresent
        resources:
          limits:
            memory: 170Mi
          requests:
            cpu: 100m
            memory: 70Mi
        args: [ "-conf", "/etc/coredns/Corefile" ]
        volumeMounts:
        - name: config-volume
          mountPath: /etc/coredns
        ports:
        - containerPort: 53
          name: dns
          protocol: UDP
        - containerPort: 53
          name: dns-tcp
          protocol: TCP
        livenessProbe:
          httpGet:
            path: /health
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 60
          timeoutSeconds: 5
          successThreshold: 1
          failureThreshold: 5
      dnsPolicy: Default
      volumes:
        - name: config-volume
          configMap:
            name: coredns
            items:
            - key: Corefile
              path: Corefile
---
apiVersion: v1
kind: Service
metadata:
  name: coredns
  namespace: kube-system
  labels:
    k8s-app: coredns
    kubernetes.io/cluster-service: "true"
    addonmanager.kubernetes.io/mode: Reconcile
    kubernetes.io/name: "CoreDNS"
spec:
  selector:
    k8s-app: coredns
  clusterIP: 10.254.0.2
  ports:
  - name: dns
    port: 53
    protocol: UDP
  - name: dns-tcp
    port: 53
    protocol: TCP

部署coredns

[root@node-01 ~]# kubectl apply -f coredns.yml
serviceaccount/coredns created
clusterrole.rbac.authorization.k8s.io/system:coredns created
clusterrolebinding.rbac.authorization.k8s.io/system:coredns created
configmap/coredns created
deployment.extensions/coredns created
service/coredns created

[root@node-01 ~]# kubectl get pod -A
NAMESPACE     NAME                       READY   STATUS    RESTARTS   AGE
kube-system   coredns-76458c6948-t5f2b   1/1     Running   0          103s
kube-system   coredns-76458c6948-v56tg   1/1     Running   0          103s

12 集成k8s到rancher

只有上面的部分完成后，才能导入到rancher集群中。

curl --insecure -sfL https://172.19.2.25:8443/v3/import/f6knmcb7pjgtdppckkdgvfz24gbdcfhpg7npjr2xh4bt9xhxlv8j89.yaml | kubectl apply -f -

大功告成！