1、实战-centos上二进制安装docker-成功测试-2022.8.4

实战：centos上二进制安装docker(成功测试) -2022.8.4

实验环境

1台centos7.7 1908虚机；(nat模式)

主机名	ip	系统版本
docker-binary	172.29.9.11	CentOS 7.7.1908

注意：个人本次实验是从之前的初始化做好的centos7.7快照恢复过来的。

实验软件

百度云位置：docker-18.06.3-ce.tgz

0、基础环境准备

(1)关闭且禁用firewalld、NetworkManager、selinux服务

systemctl stop firewalld &systemctl disable  firewalld

systemctl stop NetworkManager
systemctl disable  NetworkManager

setenforce 0
sed -i s/SELINUX=enforcing/SELINUX=disabled/ /etc/selinux/config

(2)配置网络yum源

cd /etc/yum.repos.d/
mkdir backup-`date +%F`
mv * !$

wget -O /etc/yum.repos.d/Centos-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
yum clean all
yum makecache

yum install -y net-tools
yum install -y vim
yum install -y wget
yum install -y lrzsz

(3)配置主机名

[root@hg ~]# hostnamectl --static set-hostname docker-binary
[root@hg ~]# exec bash
[root@docker-binary ~]#

1、下载二进制安装包

[root@docker-binary ~]# wget https://mirrors.aliyun.com/docker-ce/linux/static/stable/x86_64/docker-18.06.3-ce.tgz

2、复制docker 二进制文件到/usr/bin目录下

[root@docker-binary ~]# ls
docker-18.06.3-ce.tgz
[root@docker-binary ~]# tar xf docker-18.06.3-ce.tgz 
[root@docker-binary ~]# cd docker
[root@docker-binary docker]# ls
docker  docker-containerd  docker-containerd-ctr  docker-containerd-shim  dockerd  docker-init  docker-proxy  docker-runc
[root@docker-binary docker]# cp * /usr/bin/

3、生成docker.service服务启动文件

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
# 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 -H tcp://0.0.0.0:2375 -H unix://var/run/docker.sock
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
EOF

4、启动docker服务并设置开机启动

[root@docker-binary ~]# systemctl daemon-reload
[root@docker-binary ~]# systemctl start docker
[root@docker-binary ~]# systemctl enable  docker
Created symlink from /etc/systemd/system/multi-user.target.wants/docker.service to /usr/lib/systemd/system/docker.service.
[root@docker-binary ~]#

5、验证docker是否安装成功？

6、配置镜像加速

mkdir -p /etc/docker
tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["https://kvuwuws2.mirror.aliyuncs.com"]
}
EOF

systemctl daemon-reload
systemctl restart docker

7、启动一个nginx容器，并验证效果：（符合预期效果）

[root@docker-binary ~]# docker pull nginx
Using default tag: latest
latest: Pulling from library/nginx
69692152171a: Pull complete 
30afc0b18f67: Pull complete 
596b1d696923: Pull complete 
febe5bd23e98: Pull complete 
8283eee92e2f: Pull complete 
351ad75a6cfa: Pull complete 
Digest: sha256:6d75c99af15565a301e48297fa2d121e15d80ad526f8369c526324f0f7ccb750
Status: Downloaded newer image for nginx:latest
[root@docker-binary ~]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
nginx               latest              d1a364dc548d        2 days ago          133MB
[root@docker-binary ~]# docker run -d -p 80:80 nginx
f6788d53c01978b1520956bce07ed2a9ab5cc042189d13174eead774bedb7178
[root@docker-binary ~]# docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                NAMES
f6788d53c019        nginx               "/docker-entrypoint.…"   7 seconds ago       Up 6 seconds        0.0.0.0:80->80/tcp   romantic_jepsen
[root@docker-binary ~]# docker exec -it f6788d53c019 bash
root@f6788d53c019:/# echo "<h1>Linux39</h1>" > /usr/share/nginx/html/index.html
root@f6788d53c019:/#

自己笔记本浏览器输入：http://172.29.9.11/验证效果。

需要注意的问题

(1) 关于路由转发功能问题思考

默认情况，ipv4的路由转发功能是关闭的，即cat /proc/sys/net/ipv4/ip_forward默认为1；

但是一旦docker服务被安装后，这个路由转发功能会被开启的，但是cat /etc/sysctl.conf 文件里没有配置相关内容，感觉像是临时生效的(其实是永久生效的)。

这边进行测试下：

重启宿主机，查看效果：

init 6

虚机重启后现象：

虚机重启后，原来的容器停止了；但这个cat /proc/sys/net/ipv4/ip_forward的内容依然为1；此时docker服务时启动的； 关闭docker服务后，这个内容依然为1；

很奇怪，应该是自己对这方面的知识哪里有盲区，这个问题暂且搁置。

个人建议，最好手动配置永久生效：

#永久生效方法：
[root@docker-binary ~]# echo "net.ipv4.ip_forward = 1" >> /etc/sysctl.conf 
[root@docker-binary ~]# sysctl -p #生效net.ipv4.ip_forward = 1
[root@docker-binary ~]# cat /proc/sys/net/ipv4/ip_forward #查看，1代表开启网络路由转发功能1