1.1 安装kubeadm环境准备
1.1.1 环境需求
环境：centos 7.4 +
硬件需求：CPU>=2c ,内存>=2G
1.1.2 环境机器列表
| ip | role | software | 备注 |
|---|---|---|---|
| 192.168.165.198 | k8s-master | kube-apiserver kube-schduler kube-controller-manager docker flannel kubelet | |
| 192.168.165.192 | k8s-node2 | kubelet kube-proxy docker flannel | |
| 192.168.165.193 | k8s-node3 | kubelet kube-proxy docker flannel | |
| 192.168.165.194 | k8s-node4 | kubelet kube-proxy docker flannel |
1.1.3 环境初始化
- 关闭防火墙及selinux
注意：所有节点都要执行
[root@localhost ~]# systemctl stop firewalld && systemctl disable firewalld
[root@localhost ~]# sed -i 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config && setenforce 0
setenforce: SELinux is disabled
- 关闭swap分区
注意：所有节点都要执行
[root@localhost ~]# swapoff -a
[root@localhost ~]# sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab
- 分别在各个节点上设置主机名及配置hosts
[root@localhost ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.165.198 k8s-master
192.168.165.192 k8s-node2
192.168.165.193 k8s-node3
192.168.165.194 k8s-node4
- 内核调整,将桥接的IPv4流量传递到iptables的链
[root@localhost ~]# cat > /etc/sysctl.d/k8s.conf << EOF
> net.bridge.bridge-nf-call-ip6tables = 1
> net.bridge.bridge-nf-call-iptables = 1
> EOF
[root@localhost ~]# sysctl --system
* Applying /usr/lib/sysctl.d/00-system.conf ...
* Applying /usr/lib/sysctl.d/10-default-yama-scope.conf ...
kernel.yama.ptrace_scope = 0
* Applying /usr/lib/sysctl.d/50-default.conf ...
kernel.sysrq = 16
kernel.core_uses_pid = 1
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
net.ipv4.conf.all.accept_source_route = 0
net.ipv4.conf.default.promote_secondaries = 1
net.ipv4.conf.all.promote_secondaries = 1
fs.protected_hardlinks = 1
fs.protected_symlinks = 1
* Applying /etc/sysctl.d/99-sysctl.conf ...
* Applying /etc/sysctl.d/k8s.conf ...
* Applying /etc/sysctl.conf ...
- 设置系统时区并同步时间服务器
[root@localhost ~]# yum install -y ntpdate
已加载插件：fastestmirror
Determining fastest mirrors
* base: mirrors.aliyun.com
* extras: mirrors.aliyun.com
* updates: mirrors.aliyun.com
base
extras
updates
(1/4): base/7/x86_64/group_gz
(2/4): extras/7/x86_64/primary_db
(3/4): base/7/x86_64/primary_db
(4/4): updates/7/x86_64/primary_db
正在解决依赖关系
--> 正在检查事务
---> 软件包 ntpdate.x86_64.0.4.2.6p5-29.el7.centos.2 将被 安装
--> 解决依赖关系完成
依赖关系解决
============================================================================================================================
Package 架构 版
============================================================================================================================
正在安装:
ntpdate x86_64 4.
事务概要
============================================================================================================================
安装 1 软件包
总下载量：87 k
安装大小：121 k
Downloading packages:
警告：/var/cache/yum/x86_64/7/base/packages/ntpdate-4.2.6p5-29.el7.centos.2.x86_64.rpm: 头V3 RSA/SHA256 Signature, 密钥 ID f
ntpdate-4.2.6p5-29.el7.centos.2.x86_64.rpm 的公钥尚未安装
ntpdate-4.2.6p5-29.el7.centos.2.x86_64.rpm
从 file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7 检索密钥
导入 GPG key 0xF4A80EB5:
用户ID : "CentOS-7 Key (CentOS 7 Official Signing Key) <security@centos.org>"
指纹 : 6341 ab27 53d7 8a78 a7c2 7bb1 24c6 a8a7 f4a8 0eb5
软件包 : centos-release-7-6.1810.2.el7.centos.x86_64 (@anaconda)
来自 : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
正在安装 : ntpdate-4.2.6p5-29.el7.centos.2.x86_64
验证中 : ntpdate-4.2.6p5-29.el7.centos.2.x86_64
已安装:
ntpdate.x86_64 0:4.2.6p5-29.el7.centos.2
完毕！
[root@localhost ~]# ntpdate time.windows.com
4 Aug 17:13:02 ntpdate[17303]: adjust time server 20.189.79.72 offset -0.018538 sec
1.1.4 docker安装
如果没安装wget，需要安装yum install -y wget
[root@localhost ~]# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
--2021-08-04 17:21:14-- https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
正在解析主机 mirrors.aliyun.com (mirrors.aliyun.com)... 113.96.109.93, 59.53.162.242, 124.225.134.243, ...
正在连接 mirrors.aliyun.com (mirrors.aliyun.com)|113.96.109.93|:443... 已连接。
已发出 HTTP 请求，正在等待回应... 200 OK
长度：2081 (2.0K) [application/octet-stream]
正在保存至: “/etc/yum.repos.d/docker-ce.repo”
100%[=======================================================================================================================
2021-08-04 17:21:15 (154 MB/s) - 已保存 “/etc/yum.repos.d/docker-ce.repo” [2081/2081])
[root@localhost ~]# yum -y install docker-ce-18.06.1.ce-3.el7
已加载插件：fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.aliyun.com
* extras: mirrors.aliyun.com
* updates: mirrors.aliyun.com
docker-ce-stable
(1/2): docker-ce-stable/7/x86_64/primary_db
(2/2): docker-ce-stable/7/x86_64/updateinfo
正在解决依赖关系
--> 正在检查事务
---> 软件包 docker-ce.x86_64.0.18.06.1.ce-3.el7 将被 安装
--> 正在处理依赖关系 container-selinux >= 2.9，它被软件包 docker-ce-18.06.1.ce-3.el7.x86_64 需要
--> 正在处理依赖关系 libcgroup，它被软件包 docker-ce-18.06.1.ce-3.el7.x86_64 需要
--> 正在检查事务
---> 软件包 container-selinux.noarch.2.2.119.2-1.911c772.el7_8 将被 安装
--> 正在处理依赖关系 policycoreutils-python，它被软件包 2:container-selinux-2.119.2-1.911c772.el7_8.noarch 需要
---> 软件包 libcgroup.x86_64.0.0.41-21.el7 将被 安装
--> 正在检查事务
---> 软件包 policycoreutils-python.x86_64.0.2.5-34.el7 将被 安装
--> 正在处理依赖关系 policycoreutils = 2.5-34.el7，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 setools-libs >= 3.3.8-4，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 libsemanage-python >= 2.5-14，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 audit-libs-python >= 2.1.3-4，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 python-IPy，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 libqpol.so.1(VERS_1.4)(64bit)，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 libqpol.so.1(VERS_1.2)(64bit)，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 libapol.so.4(VERS_4.0)(64bit)，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 checkpolicy，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 libqpol.so.1()(64bit)，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在处理依赖关系 libapol.so.4()(64bit)，它被软件包 policycoreutils-python-2.5-34.el7.x86_64 需要
--> 正在检查事务
---> 软件包 audit-libs-python.x86_64.0.2.8.5-4.el7 将被 安装
--> 正在处理依赖关系 audit-libs(x86-64) = 2.8.5-4.el7，它被软件包 audit-libs-python-2.8.5-4.el7.x86_64 需要
---> 软件包 checkpolicy.x86_64.0.2.5-8.el7 将被 安装
---> 软件包 libsemanage-python.x86_64.0.2.5-14.el7 将被 安装
---> 软件包 policycoreutils.x86_64.0.2.5-29.el7 将被 升级
---> 软件包 policycoreutils.x86_64.0.2.5-34.el7 将被 更新
---> 软件包 python-IPy.noarch.0.0.75-6.el7 将被 安装
---> 软件包 setools-libs.x86_64.0.3.3.8-4.el7 将被 安装
--> 正在检查事务
---> 软件包 audit-libs.x86_64.0.2.8.4-4.el7 将被 升级
--> 正在处理依赖关系 audit-libs(x86-64) = 2.8.4-4.el7，它被软件包 audit-2.8.4-4.el7.x86_64 需要
---> 软件包 audit-libs.x86_64.0.2.8.5-4.el7 将被 更新
--> 正在检查事务
---> 软件包 audit.x86_64.0.2.8.4-4.el7 将被 升级
---> 软件包 audit.x86_64.0.2.8.5-4.el7 将被 更新
--> 解决依赖关系完成
依赖关系解决
============================================================================================================================
Package 架构 版本
============================================================================================================================
正在安装:
docker-ce x86_64 18.
为依赖而安装:
audit-libs-python x86_64 2.8
checkpolicy x86_64 2.5
container-selinux noarch 2:2
libcgroup x86_64 0.4
libsemanage-python x86_64 2.5
policycoreutils-python x86_64 2.5
python-IPy noarch 0.7
setools-libs x86_64 3.3
为依赖而更新:
audit x86_64 2.8
audit-libs x86_64 2.8
policycoreutils x86_64 2.5
事务概要
============================================================================================================================
安装 1 软件包 (+8 依赖软件包)
升级 ( 3 依赖软件包)
总下载量：44 M
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
(1/12): container-selinux-2.119.2-1.911c772.el7_8.noarch.rpm
(2/12): audit-libs-2.8.5-4.el7.x86_64.rpm
(3/12): audit-libs-python-2.8.5-4.el7.x86_64.rpm
(4/12): audit-2.8.5-4.el7.x86_64.rpm
(5/12): libcgroup-0.41-21.el7.x86_64.rpm
(6/12): libsemanage-python-2.5-14.el7.x86_64.rpm
(7/12): python-IPy-0.75-6.el7.noarch.rpm
(8/12): policycoreutils-python-2.5-34.el7.x86_64.rpm
(9/12): checkpolicy-2.5-8.el7.x86_64.rpm
(10/12): setools-libs-3.3.8-4.el7.x86_64.rpm
(11/12): policycoreutils-2.5-34.el7.x86_64.rpm
warning: /var/cache/yum/x86_64/7/docker-ce-stable/packages/docker-ce-18.06.1.ce-3.el7.x86_64.rpm: Header V4 RSA/SHA512 Signa
docker-ce-18.06.1.ce-3.el7.x86_64.rpm 的公钥尚未安装
(12/12): docker-ce-18.06.1.ce-3.el7.x86_64.rpm
----------------------------------------------------------------------------------------------------------------------------
总计
从 https://mirrors.aliyun.com/docker-ce/linux/centos/gpg 检索密钥
导入 GPG key 0x621E9F35:
用户ID : "Docker Release (CE rpm) <docker@docker.com>"
指纹 : 060a 61c5 1b55 8a7f 742b 77aa c52f eb6b 621e 9f35
来自 : https://mirrors.aliyun.com/docker-ce/linux/centos/gpg
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
正在更新 : audit-libs-2.8.5-4.el7.x86_64
正在更新 : policycoreutils-2.5-34.el7.x86_64
正在安装 : libcgroup-0.41-21.el7.x86_64
正在安装 : audit-libs-python-2.8.5-4.el7.x86_64
正在安装 : setools-libs-3.3.8-4.el7.x86_64
正在安装 : checkpolicy-2.5-8.el7.x86_64
正在安装 : python-IPy-0.75-6.el7.noarch
正在安装 : libsemanage-python-2.5-14.el7.x86_64
正在安装 : policycoreutils-python-2.5-34.el7.x86_64
正在安装 : 2:container-selinux-2.119.2-1.911c772.el7_8.noarch
setsebool: SELinux is disabled.
正在安装 : docker-ce-18.06.1.ce-3.el7.x86_64
正在更新 : audit-2.8.5-4.el7.x86_64
清理 : policycoreutils-2.5-29.el7.x86_64
清理 : audit-2.8.4-4.el7.x86_64
清理 : audit-libs-2.8.4-4.el7.x86_64
验证中 : audit-libs-2.8.5-4.el7.x86_64
验证中 : audit-2.8.5-4.el7.x86_64
验证中 : docker-ce-18.06.1.ce-3.el7.x86_64
验证中 : libsemanage-python-2.5-14.el7.x86_64
验证中 : policycoreutils-2.5-34.el7.x86_64
验证中 : 2:container-selinux-2.119.2-1.911c772.el7_8.noarch
验证中 : python-IPy-0.75-6.el7.noarch
验证中 : checkpolicy-2.5-8.el7.x86_64
验证中 : policycoreutils-python-2.5-34.el7.x86_64
验证中 : audit-libs-python-2.8.5-4.el7.x86_64
验证中 : setools-libs-3.3.8-4.el7.x86_64
验证中 : libcgroup-0.41-21.el7.x86_64
验证中 : policycoreutils-2.5-29.el7.x86_64
验证中 : audit-libs-2.8.4-4.el7.x86_64
验证中 : audit-2.8.4-4.el7.x86_64
已安装:
docker-ce.x86_64 0:18.06.1.ce-3.el7
作为依赖被安装:
audit-libs-python.x86_64 0:2.8.5-4.el7 checkpolicy.x86_64 0:2.5-8.el7 container-selinux.noarch 2:2.119.2-1.911c
python-IPy.noarch 0:0.75-6.el7 setools-libs.x86_64 0:3.3.8-4.el7
作为依赖被升级:
audit.x86_64 0:2.8.5-4.el7 audit-libs.x86_64 0:2.8.5-4.el7
完毕！
[root@localhost ~]# systemctl enable docker && systemctl start docker
Created symlink from /etc/systemd/system/multi-user.target.wants/docker.service to /usr/lib/systemd/system/docker.service.
[root@localhost ~]# docker --version
Docker version 18.06.1-ce, build e68fc7a
1.1.5 添加kubernetes YUM软件源
[root@localhost ~]# cat > /etc/yum.repos.d/kubernetes.repo << EOF
> [kubernetes]
> name=Kubernetes
> baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
> enabled=1
> gpgcheck=0
> repo_gpgcheck=0
> gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package
> EOF
1.1.6 安装kubeadm,kubelet和kubectl
[root@localhost ~]# yum install -y kubelet-1.15.0 kubeadm-1.15.0 kubectl-1.15.0
已加载插件：fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.aliyun.com
* extras: mirrors.aliyun.com
* updates: mirrors.aliyun.com
kubernetes
kubernetes/primary
kubernetes
正在解决依赖关系
--> 正在检查事务
---> 软件包 kubeadm.x86_64.0.1.15.0-0 将被 安装
--> 正在处理依赖关系 kubernetes-cni >= 0.7.5，它被软件包 kubeadm-1.15.0-0.x86_64 需要
--> 正在处理依赖关系 cri-tools >= 1.11.0，它被软件包 kubeadm-1.15.0-0.x86_64 需要
---> 软件包 kubectl.x86_64.0.1.15.0-0 将被 安装
---> 软件包 kubelet.x86_64.0.1.15.0-0 将被 安装
--> 正在处理依赖关系 socat，它被软件包 kubelet-1.15.0-0.x86_64 需要
--> 正在处理依赖关系 conntrack，它被软件包 kubelet-1.15.0-0.x86_64 需要
--> 正在检查事务
---> 软件包 conntrack-tools.x86_64.0.1.4.4-7.el7 将被 安装
--> 正在处理依赖关系 libnetfilter_cttimeout.so.1(LIBNETFILTER_CTTIMEOUT_1.1)(64bit)，它被软件包 conntrack-tools-1.4.4-7.el7.
--> 正在处理依赖关系 libnetfilter_cttimeout.so.1(LIBNETFILTER_CTTIMEOUT_1.0)(64bit)，它被软件包 conntrack-tools-1.4.4-7.el7.
--> 正在处理依赖关系 libnetfilter_cthelper.so.0(LIBNETFILTER_CTHELPER_1.0)(64bit)，它被软件包 conntrack-tools-1.4.4-7.el7.x8
--> 正在处理依赖关系 libnetfilter_queue.so.1()(64bit)，它被软件包 conntrack-tools-1.4.4-7.el7.x86_64 需要
--> 正在处理依赖关系 libnetfilter_cttimeout.so.1()(64bit)，它被软件包 conntrack-tools-1.4.4-7.el7.x86_64 需要
--> 正在处理依赖关系 libnetfilter_cthelper.so.0()(64bit)，它被软件包 conntrack-tools-1.4.4-7.el7.x86_64 需要
---> 软件包 cri-tools.x86_64.0.1.13.0-0 将被 安装
---> 软件包 kubernetes-cni.x86_64.0.0.8.7-0 将被 安装
---> 软件包 socat.x86_64.0.1.7.3.2-2.el7 将被 安装
--> 正在检查事务
---> 软件包 libnetfilter_cthelper.x86_64.0.1.0.0-11.el7 将被 安装
---> 软件包 libnetfilter_cttimeout.x86_64.0.1.0.0-7.el7 将被 安装
---> 软件包 libnetfilter_queue.x86_64.0.1.0.2-2.el7_2 将被 安装
--> 解决依赖关系完成
依赖关系解决
============================================================================================================================
Package 架构
============================================================================================================================
正在安装:
kubeadm x86_64
kubectl x86_64
kubelet x86_64
为依赖而安装:
conntrack-tools x86_64
cri-tools x86_64
kubernetes-cni x86_64
libnetfilter_cthelper x86_64
libnetfilter_cttimeout x86_64
libnetfilter_queue x86_64
socat x86_64
事务概要
============================================================================================================================
安装 3 软件包 (+7 依赖软件包)
总下载量：64 M
安装大小：271 M
Downloading packages:
(1/10): conntrack-tools-1.4.4-7.el7.x86_64.rpm
(2/10): 14bfe6e75a9efc8eca3f638eb22c7e2ce759c67f95b43b16fae4ebabde1549f3-cri-tools-1.13.0-0.x86_64.rpm
(3/10): 7143f62ad72a1eb1849d5c1e9490567d405870d2c00ab2b577f1f3bdf9f547ba-kubeadm-1.15.0-0.x86_64.rpm
(4/10): 3d5dd3e6a783afcd660f9954dec3999efa7e498cac2c14d63725fafa1b264f14-kubectl-1.15.0-0.x86_64.rpm
(5/10): libnetfilter_cttimeout-1.0.0-7.el7.x86_64.rpm
(6/10): libnetfilter_queue-1.0.2-2.el7_2.x86_64.rpm
(7/10): libnetfilter_cthelper-1.0.0-11.el7.x86_64.rpm
(8/10): socat-1.7.3.2-2.el7.x86_64.rpm
(9/10): 557c2f4e11a3ab262c72a52d240f2f440c63f539911ff5e05237904893fc36bb-kubelet-1.15.0-0.x86_64.rpm
(10/10): db7cb5cb0b3f6875f54d10f02e625573988e3e91fd4fc5eef0b1876bb18604ad-kubernetes-cni-0.8.7-0.x86_64.rpm
----------------------------------------------------------------------------------------------------------------------------
总计
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
正在安装 : libnetfilter_cttimeout-1.0.0-7.el7.x86_64
正在安装 : socat-1.7.3.2-2.el7.x86_64
正在安装 : kubectl-1.15.0-0.x86_64
正在安装 : cri-tools-1.13.0-0.x86_64
正在安装 : libnetfilter_queue-1.0.2-2.el7_2.x86_64
正在安装 : libnetfilter_cthelper-1.0.0-11.el7.x86_64
正在安装 : conntrack-tools-1.4.4-7.el7.x86_64
正在安装 : kubernetes-cni-0.8.7-0.x86_64
正在安装 : kubelet-1.15.0-0.x86_64
正在安装 : kubeadm-1.15.0-0.x86_64
验证中 : libnetfilter_cthelper-1.0.0-11.el7.x86_64
验证中 : kubeadm-1.15.0-0.x86_64
验证中 : kubernetes-cni-0.8.7-0.x86_64
验证中 : kubelet-1.15.0-0.x86_64
验证中 : libnetfilter_queue-1.0.2-2.el7_2.x86_64
验证中 : cri-tools-1.13.0-0.x86_64
验证中 : kubectl-1.15.0-0.x86_64
验证中 : socat-1.7.3.2-2.el7.x86_64
验证中 : libnetfilter_cttimeout-1.0.0-7.el7.x86_64
验证中 : conntrack-tools-1.4.4-7.el7.x86_64
已安装:
kubeadm.x86_64 0:1.15.0-0 kubectl.x86_64 0:1.15.0-0
作为依赖被安装:
conntrack-tools.x86_64 0:1.4.4-7.el7 cri-tools.x86_64 0:1.13.0-0 kubernetes-cni.x86_64 0:0.8.7-0 libnetfilter_cthelper.x86
完毕！
[root@localhost ~]# systemctl enable kubelet
Created symlink from /etc/systemd/system/multi-user.target.wants/kubelet.service to /usr/lib/systemd/system/kubelet.service
2.1 部署Kubernetes Master
master初始化
[root@k8s-master ~]# kubeadm init --apiserver-advertise-address=192.168.165.198 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.15.0 --service-cidr=10.1.0.0/16
[init] Using Kubernetes version: v1.15.0
[preflight] Running pre-flight checks
[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
报错了，出现[WARNING IsDockerSystemdCheck]，是由于docker的Cgroup Driver和kubelet的Cgroup Driver不一致导致的，此处选择修改docker的和kubelet一致
编辑文件/usr/lib/systemd/system/docker.service, 修改ExecStart=/usr/bin/dockerd --exec-opt native.cgroupdriver=systemd
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target
[Service]
Type=notify
# the default is not to use systemd for cgroups because the delegate issues still
# exists and systemd currently does not support the cgroup feature set required
# for containers run by docker
# ExecStart=/usr/bin/dockerd
ExecStart=/usr/bin/dockerd --exec-opt native.cgroupdriver=systemd
ExecReload=/bin/kill -s HUP $MAINPID
# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
# Uncomment TasksMax if your systemd version supports it.
# Only systemd 226 and above support this version.
#TasksMax=infinity
TimeoutStartSec=0
# set delegate yes so that systemd does not reset the cgroups of docker containers
Delegate=yes
# kill only the docker process, not all processes in the cgroup
KillMode=process
# restart the docker process if it exits prematurely
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s
[Install]
WantedBy=multi-user.target
重启docker，可以看到docker info | grep Cgroup的输出变成了systemd
[root@k8s-master ~]# docker info | grep Cgroup
Cgroup Driver: cgroupfs
[root@k8s-master ~]# systemctl daemon-reload
[root@k8s-master ~]# systemctl restart docker
[root@k8s-master ~]# vi /usr/lib/systemd/system/docker.service
[root@k8s-master ~]# vi /usr/lib/systemd/system/docker.service
[root@k8s-master ~]# systemctl daemon-reload
[root@k8s-master ~]# systemctl restart docker
[root@k8s-master ~]# docker info | grep Cgroup
Cgroup Driver: systemd
再次执行,可以看到已经执行成功
[root@k8s-master ~]# kubeadm init --apiserver-advertise-address=192.168.165.198 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.15.0 --service-cidr=10.1.0.0/16 --pod-network-cidr=10.244.0.0/16
[init] Using Kubernetes version: v1.15.0
[preflight] Running pre-flight checks
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Activating the kubelet service
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [k8s-master localhost] and IPs [192.168.165.198 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-master localhost] and IPs [192.168.165.198 127.0.0.1 ::1]
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [k8s-master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.1.0.1 192.168.165.198]
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 15.005161 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.15" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node k8s-master as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node k8s-master as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: 283bmn.5s8oey15nquac4mw
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 192.168.165.198:6443 --token 283bmn.5s8oey15nquac4mw \
--discovery-token-ca-cert-hash sha256:b4e5d42f49230d88eeed7f7af3c49d6f2f3d1c1146df1640545636e8490e3175
[root@k8s-master ~]#
根据提示操作，如果需要回退init，可以kubeadm reset,同时要删除$HOME/.kube/config和/var/lib/etcd,再次执行kubeadm init即可
[root@k8s-master ~]# mkdir -p $HOME/.kube
[root@k8s-master ~]# sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@k8s-master ~]# sudo chown $(id -u):$(id -g) $HOME/.kube/config
[root@k8s-master ~]#
在其他子节点执行下面命令即可加入集群，如果执行出错，可以加上 --v=2查看具体报错信息
[root@k8s-node3 ~]# kubeadm join 192.168.165.198:6443 --token m8x4sa.ohcpv36ddk5dlivb --discovery-token-ca-cert-hash sha256:98aa44463bafe37f911b91d87b550574ef255ad665ffa62b23ebe71cd65a6519
[preflight] Running pre-flight checks
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
[kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.15" ConfigMap in the kube-system namespace
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Activating the kubelet service
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
This node has joined the cluster:
* Certificate signing request was sent to apiserver and a response was received.
* The Kubelet was informed of the new secure connection details.
Run 'kubectl get nodes' on the control-plane to see this node join the cluster.
[root@k8s-node3 ~]#
添加完节点后，可以通过kubectl get node查看当前节点，发现报错了，原因：kubernetes master没有与本机绑定，集群初始化的时候没有绑定，此时设置在本机的环境变量即可解决问题，如果在其他节点也出现了同样的报错，可以将/etc/kubernetes/admin.conf通过scp复制到其他节点，再设置环境变量即可解决
[root@k8s-master ~]# kubectl get node
The connection to the server localhost:8080 was refused - did you specify the right host or port?
[root@k8s-master ~]# echo "export KUBECONFIG=/etc/kubernetes/admin.conf" >> /etc/profile
[root@k8s-master ~]# source /etc/profile
[root@k8s-master ~]# kubectl get node
NAME STATUS ROLES AGE VERSION
k8s-master NotReady master 13h v1.15.0
安装网络插件
只需要在master安装
[root@k8s-master ~]# wget https://raw.githubusercontent.com/coreos/flannel/a70459be0084506e4ec919aa1c114638878db11b/Documentation/kube-flannel.yml
[root@k8s-master ~]# kubectl apply -f kube-flannel.yml
[root@k8s-master ~]# ps -ef|grep flannel
root 913 890 0 14:22 ? 00:00:01 /opt/bin/flanneld --ip-masq --kube-subnet-mgr
root 10725 16706 0 14:42 pts/0 00:00:00 grep --color=auto flannel
到此位置，搭建已完成
测试k8s集群
root@k8s-master ~]# kubectl create deployment nginx --image=nginx
deployment.apps/nginx created
[root@k8s-master ~]# kubectl expose deployment nginx --port=80 --type=NodePort
service/nginx exposed
[root@k8s-master ~]# kubectl get pods,svc
NAME READY STATUS RESTARTS AGE
pod/nginx-554b9c67f9-pnc5g 1/1 Running 0 4m26s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.1.0.1 <none> 443/TCP 18h
service/nginx NodePort 10.1.1.157 <none> 80:30755/TCP 4m8s
[root@k8s-master ~]# curl http://192.168.165.198:30755
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
如上所示，已经能访问到nginx了
PS：由于在之前，我漏掉了一个步骤,没有指定--pod-network-cidr=10.244.0.0/16，导致安装flannel持续报错，花费好多时间查找
[root@k8s-master ~]# kubeadm init --apiserver-advertise-address=192.168.165.198 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.15.0 --service-cidr=10.1.0.0/16 --pod-network-cidr=10.244.0.0/16
如果未指定--pod-network-cidr=10.244.0.0/16，则会出现下列报错
[root@k8s-master ~]# kubectl get pods --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system coredns-bccdc95cf-rd6w2 0/1 ContainerCreating 0 17h
kube-system coredns-bccdc95cf-rkrtm 0/1 ContainerCreating 0 17h
kube-system etcd-k8s-master 1/1 Running 0 17h
kube-system kube-apiserver-k8s-master 1/1 Running 0 17h
kube-system kube-controller-manager-k8s-master 1/1 Running 0 17s
kube-system kube-flannel-ds-amd64-h4gj5 0/1 CrashLoopBackOff 39 3h1m
kube-system kube-flannel-ds-amd64-qv52d 0/1 CrashLoopBackOff 39 3h1m
kube-system kube-flannel-ds-amd64-tddjl 0/1 Error 40 3h1m
kube-system kube-flannel-ds-amd64-z2gbl 0/1 CrashLoopBackOff 39 3h1m
kube-system kube-proxy-4zkbp 1/1 Running 0 3h22m
kube-system kube-proxy-lrgz7 1/1 Running 0 17h
kube-system kube-proxy-nrxdd 1/1 Running 0 3h4m
kube-system kube-proxy-vws6d 1/1 Running 0 3h23m
kube-system kube-scheduler-k8s-master 1/1 Running 0 17h
查看其具体日志发现,报错为Error registering network: failed to acquire lease: node "k8s-node3" pod cidr not assigned
[root@k8s-master ~]# kubectl logs kube-flannel-ds-amd64-h4gj5
Error from server (NotFound): pods "kube-flannel-ds-amd64-h4gj5" not found
[root@k8s-master ~]# kubectl logs kube-flannel-ds-amd64-h4gj5 -n kube-system
I0805 06:17:12.825680 1 main.go:514] Determining IP address of default interface
I0805 06:17:12.826441 1 main.go:527] Using interface with name ens192 and address 192.168.165.193
I0805 06:17:12.826499 1 main.go:544] Defaulting external address to interface address (192.168.165.193)
I0805 06:17:13.020546 1 kube.go:126] Waiting 10m0s for node controller to sync
I0805 06:17:13.020895 1 kube.go:309] Starting kube subnet manager
I0805 06:17:14.021040 1 kube.go:133] Node controller sync successful
I0805 06:17:14.021153 1 main.go:244] Created subnet manager: Kubernetes Subnet Manager - k8s-node3
I0805 06:17:14.021176 1 main.go:247] Installing signal handlers
I0805 06:17:14.021348 1 main.go:386] Found network config - Backend type: vxlan
I0805 06:17:14.021504 1 vxlan.go:120] VXLAN config: VNI=1 Port=0 GBP=false DirectRouting=false
E0805 06:17:14.022070 1 main.go:289] Error registering network: failed to acquire lease: node "k8s-node3" pod cidr not assigned
I0805 06:17:14.022189 1 main.go:366] Stopping shutdownHandler...
上述报错是指未指定pod cidr，需要vim /etc/kubernetes/manifests/kube-controller-manager.yaml
command中增加两个参数：
--allocate-node-cidrs=true
--cluster-cidr=10.244.0.0/16
[root@k8s-master ~]# vi /etc/kubernetes/manifests/kube-controller-manager.yaml
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
component: kube-controller-manager
tier: control-plane
name: kube-controller-manager
namespace: kube-system
spec:
containers:
- command:
- kube-controller-manager
- --authentication-kubeconfig=/etc/kubernetes/controller-manager.conf
- --authorization-kubeconfig=/etc/kubernetes/controller-manager.conf
- --bind-address=127.0.0.1
- --client-ca-file=/etc/kubernetes/pki/ca.crt
- --cluster-signing-cert-file=/etc/kubernetes/pki/ca.crt
- --cluster-signing-key-file=/etc/kubernetes/pki/ca.key
- --controllers=*,bootstrapsigner,tokencleaner
- --kubeconfig=/etc/kubernetes/controller-manager.conf
- --leader-elect=true
- --requestheader-client-ca-file=/etc/kubernetes/pki/front-proxy-ca.crt
- --root-ca-file=/etc/kubernetes/pki/ca.crt
- --service-account-private-key-file=/etc/kubernetes/pki/sa.key
- --use-service-account-credentials=true
- --allocate-node-cidrs=true
- --cluster-cidr=10.244.0.0/16
image: registry.aliyuncs.com/google_containers/kube-controller-manager:v1.15.0
再执行systemctl restart kubelet，即可看到全部都变成了raedy的状态
[root@k8s-master ~]# kubectl get pods --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system coredns-bccdc95cf-rd6w2 1/1 Running 0 18h
kube-system coredns-bccdc95cf-rkrtm 1/1 Running 0 18h
kube-system etcd-k8s-master 1/1 Running 0 18h
kube-system kube-apiserver-k8s-master 1/1 Running 0 18h
kube-system kube-controller-manager-k8s-master 1/1 Running 0 5m42s
kube-system kube-flannel-ds-amd64-h4gj5 1/1 Running 41 3h7m
kube-system kube-flannel-ds-amd64-qv52d 1/1 Running 40 3h7m
kube-system kube-flannel-ds-amd64-tddjl 1/1 Running 42 3h7m
kube-system kube-flannel-ds-amd64-z2gbl 1/1 Running 40 3h7m
kube-system kube-proxy-4zkbp 1/1 Running 0 3h27m
kube-system kube-proxy-lrgz7 1/1 Running 0 18h
kube-system kube-proxy-nrxdd 1/1 Running 0 3h10m
kube-system kube-proxy-vws6d 1/1 Running 0 3h28m
kube-system kube-scheduler-k8s-master 1/1 Running 0 18h
安装结束后一些配置文件路径：
[root@k8s-master manifests]# pwd
/etc/kubernetes/manifests
[root@k8s-master manifests]# ls
etcd.yaml kube-apiserver.yaml kube-controller-manager.yaml kube-scheduler.yaml
