centos7 docker安装

步骤一：centos系统设置

##关闭selinux
#setenforce 0
sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config
##关闭防火墙
systemctl stop firewalld.service && systemctl disable firewalld.service
##修改时区
ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
##修改系统语言环境
echo 'LANG="en_US.UTF-8"' >> /etc/profile;source /etc/profile


##kernel性能调优
cat >> /etc/sysctl.conf<> /etc/security/limits.conf < /etc/yum.repos.d/CentOS-Base.repo
# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client.  You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the 
# remarked out baseurl= line instead.
#
#

[base]
name=CentOS-$releasever - Base - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/os/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/os/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

#released updates
[updates]
name=CentOS-$releasever - Updates - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/updates/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/updates/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/extras/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/extras/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/centosplus/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/centosplus/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

#contrib - packages by Centos Users
[contrib]
name=CentOS-$releasever - Contrib - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/contrib/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/contrib/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/contrib/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

EOF

步骤二：docker-ce安装

因为CentOS的安全限制，通过RKE安装K8S集群时候无法使用root账户。所以，建议CentOS用户使用非root用户来运行docker,不管是RKE还是custom安装k8s,详情查看无法为主机配置SSH隧道。

##安装docker
# 定义用户名
NEW_USER=docker
# 添加用户(可选)
sudo adduser $NEW_USER
# 为新用户设置密码
sudo passwd $NEW_USER
# 为新用户添加sudo权限
sudo echo "$NEW_USER ALL=(ALL) ALL" >> /etc/sudoers
# 卸载旧版本Docker软件
sudo yum remove docker \
              docker-client \
              docker-client-latest \
              docker-common \
              docker-latest \
              docker-latest-logrotate \
              docker-logrotate \
              docker-selinux \
              docker-engine-selinux \
              docker-engine \
              container*
# 定义安装版本
export docker_version=18.06.3
#export docker_version=19.03.15
# step 1: 安装必要的一些系统工具
#sudo yum update -y;
sudo yum install -y yum-utils device-mapper-persistent-data \
    lvm2 bash-completion;
# Step 2: 添加软件源信息
sudo yum-config-manager --add-repo \
    http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo;
# Step 3: 更新并安装 Docker-CE
sudo yum makecache all;
version=$(yum list docker-ce.x86_64 --showduplicates | sort -r|grep ${docker_version}|awk '{print $2}');
sudo yum -y install --setopt=obsoletes=0 docker-ce-${version} docker-ce-selinux-${version};
# 如果已经安装高版本Docker,可进行降级安装(可选)
#yum downgrade --setopt=obsoletes=0 -y docker-ce-${version} docker-ce-selinux-${version};
# 把当前用户加入docker组
sudo usermod -aG docker $NEW_USER;
# 设置开机启动
sudo systemctl enable docker;

mkdir -p /etc/docker

#配置docker
cat << 'EOF' >/etc/docker/daemon.json
{
    "oom-score-adjust": -1000,
    "max-concurrent-downloads": 3,
    "max-concurrent-uploads": 5,
    "registry-mirrors": [ "https://8j2m7k20.mirror.aliyuncs.com" ],
    "graph": "/data/docker",
    "storage-driver": "overlay2",
    "storage-opts": ["overlay2.override_kernel_check=true"],
    "log-driver": "json-file",
    "log-opts": { "max-size":"10m","max-file":"3" }
}

EOF

systemctl restart docker

说明：docker配置

防止 docker 服务 OOM

"oom-score-adjust": -1000,

配置镜像下载和上传并发数

从Docker1.12开始，支持自定义下载和上传镜像的并发数，默认值上传为3个并发，下载为5个并发。通过添加”max-concurrent-downloads”和”max-concurrent-uploads”参数对其修改:

"max-concurrent-downloads": 3,
"max-concurrent-uploads": 5,

配置镜像加速地址

编辑/etc/docker/daemon.json加入以下内容

"registry-mirrors": [ "https://8j2m7k20.mirror.aliyuncs.com"],

配置insecure-registries私有仓库

Docker默认只信任TLS加密的仓库地址(https)，所有非https仓库默认无法登陆也无法拉取镜像。insecure-registries字面意思为不安全的仓库，通过添加这个参数对非https仓库进行授信。可以设置多个insecure-registries地址，以数组形式书写，地址不能添加协议头(http)。
编辑/etc/docker/daemon.json加入以下内容:

{
"insecure-registries": ["192.168.1.100","IP:PORT"]
}

配置docker数据存储位置

"graph": "/data/docker",

配置Docker存储驱动

OverlayFS是一个新一代的联合文件系统，类似于AUFS，但速度更快，实现更简单。Docker为OverlayFS提供了两个存储驱动程序:旧版的overlay，新版的overlay2(更稳定)。
先决条件:

overlay2: Linux内核版本4.0或更高版本，或使用内核版本3.10.0-514+的RHEL或CentOS。
overlay: 主机Linux内核版本3.18+
支持的磁盘文件系统
- ext4(仅限RHEL 7.1)
- xfs(RHEL7.2及更高版本)，需要启用d_type=true。 >具体详情参考 Docker Use the OverlayFS storage driver