8.28-回顾+容器与主机之间的通信+跨主机容器之间的通信
一、回顾
1.启动docker
systemctl start docker2.拉取registry
docker pull registry3.启动镜像，同时挂载目录（保存镜像）端口映射5000
docker run -d -v /regist/:/var/lib/registry/ -p5000:5000 registry:latest4.修改/etc/docker/daemon.json
vim /etc/docker/daemon.json.....
,
"insecure-registries":["http://192.168.2.30:5000"
]5.重启docker
systemctl restart docker6.访问测试仓库信息
# 查看仓库目录
[root@docker ~]# curl localhost:5000/v2/_catalog
{"repositories":["centos","centosnginx"]}7.上传
# 打标签
[root@docker ~]# docker tag centos:nginx 192.168.2.30:5000/centosnginx:v0# 将打标签的镜像上传
[root@docker ~]# docker push 192.168.2.30:5000/centosnginx:v0
The push refers to repository [192.168.2.30:5000/centosnginx]
715d477d6a7d: Pushed
5700116c3db7: Pushed
82890c106451: Pushed
8c519ad003b5: Mounted from centos
acbca50d3a83: Mounted from centos
75cdf155cf76: Mounted from centos
07d4b334a739: Mounted from centos
74ddd0ec08fa: Mounted from centos
v0: digest: sha256:5fb4d1018f32c53f3b21f17771bfb6b9832e76b790426b9f4c067f4c75003deb size: 1997# 查看镜像
[root@docker ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
192.168.2.30:5000/centosnginx v0 4a14f7d33da9 18 hours ago 422MB
centos nginx 4a14f7d33da9 18 hours ago 422MB
centos httpd ebbf109944f1 19 hours ago 338MB
centos yum 69f3775bce0c 19 hours ago 272MB
192.168.2.30:5000/centos yum ee9375ac855c 19 hours ago 272MB
registry latest cfb4d9904335 11 months ago 25.4MB
centos latest 5d0da3dc9764 2 years ago 231MB8.下载
# 重建一台机器，尝试下载私有仓库的镜像# 上传docker.sh脚本
[root@haha ~]# rz -E
rz waiting to receive.# 运行docker脚本
[root@haha ~]# source docker.sh # 编辑配置文件
[root@haha ~]# vim /etc/docker/daemon.json# 写私有仓库的ip和端口
{"insecure-registries":["http://192.168.2.30:5000"]
}# 重新启动docker服务
[root@haha ~]# systemctl restart docker# 关闭本机的防火墙
[root@haha ~]# ststemctl stop firewalld# 拉取私有仓库的镜像
[root@haha ~]# docker pull 192.168.2.30:5000/centosnginx:v0
v0: Pulling from centosnginx
a1d0c7532777: Pull complete
5a3d9ba04912: Pull complete
ca847d29e107: Pull complete
46aacd2dd646: Pull complete
30902bbca4a1: Pull complete
4859db75d191: Pull complete
ea0b1348be03: Pull complete
2796eebf9904: Pull complete
Digest: sha256:5fb4d1018f32c53f3b21f17771bfb6b9832e76b790426b9f4c067f4c75003deb
Status: Downloaded newer image for 192.168.2.30:5000/centosnginx:v0
192.168.2.30:5000/centosnginx:v0# 查看拉取的镜像
[root@haha ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
192.168.2.30:5000/centosnginx v0 4a14f7d33da9 18 hours ago 422MB# 测试拉取的镜像
[root@haha ~]# docker run -d --name c8 192.168.2.30:5000/centosnginx:v0
decd8137f46ea29eb4012d9cc4be2a993ca2f3e6a0deeb2dfc18c3ceffbcb829[root@haha ~]# docker ps --all
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
decd8137f46e 192.168.2.30:5000/centosnginx:v0 "/bin/sh -c /usr/sbi…" About a minute ago Up About a minute 80/tcp c8二、跨主机容器之间通讯
# 创建容器
[root@docker ~]# docker run -d --name haha -p80:80/tcp centos:nginx
4f1af9bb44ed0894a7ace10ebd01cd5c136c9a10be7f5f63a1b54e482e8d2dad# 查看容器
[root@docker ~]# docker ps -all
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
4f1af9bb44ed centos:nginx "/bin/sh -c /usr/sbi…" 8 hours ago Exited (0) 1 second ago haha# 安装bridge-utils
[root@docker ~]# yum -y install bridge-utils.x86_64# 停止docker服务
[root@docker ~]# systemctl stop docker
Warning: Stopping docker.service, but it can still be activated by:docker.socket# 显示网桥信息
[root@docker ~]# brctl show
bridge name bridge id STP enabled interfaces
docker0 8000.0242cb7fc4ce no # 启动docker服务
[root@docker ~]# systemctl start docker# 启动容器
[root@docker ~]# docker start haha
haha# 查看网桥信息
[root@docker ~]# brctl show
bridge name bridge id STP enabled interfaces
docker0 8000.0242cb7fc4ce no veth5c3d783# 查看跨主机容器之间的通信方式
[root@docker ~]# docker network ls
NETWORK ID NAME DRIVER SCOPE
c1adfec7cffc bridge bridge local
d2749f541daa host host local
dc16f8943851 none null local
# bridge-网桥模式
# host-仅主机模式
# none-独立的# 接连创建两个容器，就会发现他们的地址是连着的
# 创建容器
[root@docker ~]# docker run -it centos:latest /bin/bash# 退出不中断
[root@f40505c2a977 /]# [root@docker ~]## 查看容器ip
[root@docker ~]# docker inspect f4|grep IPA"SecondaryIPAddresses": null,"IPAddress": "172.17.0.2","IPAMConfig": null,"IPAddress": "172.17.0.2",# 创建容器
[root@docker ~]# docker run -it centos:latest /bin/bash# 退出不中断
[root@0558cad162d7 /]# [root@docker ~]# # 查看容器ip
[root@docker ~]# docker inspect 0558|grep IPA"SecondaryIPAddresses": null,"IPAddress": "172.17.0.3","IPAMConfig": null,"IPAddress": "172.17.0.3",# 进行本主机和所创建容器的通信# 在宿主机的ls下查到的内容
[root@docker ~]# ls /
bin dev home lib64 mnt proc root sbin srv tmp var
boot etc lib media opt regist run source sys usr# 创建能与主机通信的容器
[root@docker ~]# docker run -it --network host centos:yum /bin/bash# 查看ls，发现和宿主机的一样
[root@docker /]# ls
bin etc lib lost+found mnt proc run srv tmp var
dev home lib64 media opt root sbin sys usr# 退出容器不中断
[root@docker /]# [root@docker ~]# # 查看容器的ip地址，发现是空的
[root@docker ~]# docker inspect 30e|grep IPA"SecondaryIPAddresses": null,"IPAddress": "","IPAMConfig": null,"IPAddress": "",# 安装iproute
[root@docker /]# yum -y install iproute# 查看ip，发现可以查到宿主机的ip
[root@docker /]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:24:a3:0f brd ff:ff:ff:ff:ff:ffinet 192.168.2.30/24 brd 192.168.2.255 scope global noprefixroute ens33valid_lft forever preferred_lft foreverinet6 fe80::f09d:7503:dea1:e7ab/64 scope link noprefixroute valid_lft forever preferred_lft forever
3: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default link/ether 02:42:cb:7f:c4:ce brd ff:ff:ff:ff:ff:ffinet 172.17.0.1/16 brd 172.17.255.255 scope global docker0valid_lft forever preferred_lft foreverinet6 fe80::42:cbff:fe7f:c4ce/64 scope link valid_lft forever preferred_lft forever
11: veth6c87079@if10: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default link/ether 6a:47:f4:af:fa:ca brd ff:ff:ff:ff:ff:ff link-netnsid 0inet6 fe80::6847:f4ff:feaf:faca/64 scope link valid_lft forever preferred_lft forever
13: vethc725a6f@if12: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default link/ether 9a:d6:09:6b:fb:70 brd ff:ff:ff:ff:ff:ff link-netnsid 1inet6 fe80::98d6:9ff:fe6b:fb70/64 scope link valid_lft forever preferred_lft forever# 给容器下载httpd
[root@docker /]# yum -y install httpd# 给容器编辑httpd测试页面
[root@docker /]# echo "haha" > /var/www/html/index.html# 启动httpd服务（报错）
[root@docker /]# systemctl start httpd
System has not been booted with systemd as init system (PID 1). Can't operate.
Failed to connect to bus: Host is down# 使用此命令启动httpd服务
[root@docker /]# httpd -k start
AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using fe80::f09d:7503:dea1:e7ab. Set the 'ServerName' directive globally to suppress this message# 在容器内访问测试页面
[root@docker /]# curl localhost
haha# 退出容器不中断
[root@docker /]# [root@docker ~]# # 在宿主机中访问在容器中编辑的httpd测试页面
[root@docker ~]# curl 192.168.2.30
haha# 关闭防火墙
[root@docker ~]# systemctl stop firewalld使用浏览器访问容器中编辑的httpd的测试页面
192.168.2.30
三、跨主机容器之间的通信
| 主机名 | ip | 功能 | 安装软件 |
|---|---|---|---|
| node1 | 192.168.2.10 | 主控主机 | etcd，flannel，docker |
| node2 | 192.168.2.11 | 被控主机 | etcd，docker |
主控
1.安装软件
# 安装etcd数据库
[root@node1 ~]# yum -y install etcd# 安装flannel
[root@node1 ~]# yum -y install flannel2.修改etcd数据库配置
# 配置启动 etcd
# 修改配置文件
[root@node1 ~]# vim /etc/etcd/etcd.conf
6 ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379,http://0.0.0.0:4001"
21 ETCD_ADVERTISE_CLIENT_URLS="http://192.168.2.10:2379,http://192.168.2.10:4001"3.启动数据库
[root@node1 ~]# systemctl restart etcd4.测试端口
# 查看端口看有没有启动成功[root@node1 ~]# netstat -lnput|grep 2379
tcp6 0 0 :::2379 :::* LISTEN 1608/etcd
[root@node1 ~]# netstat -lnput|grep 4001
tcp6 0 0 :::4001 :::* LISTEN 1608/etcd 5.设置开机自启动
# 设置开机自启[root@node1 ~]# systemctl enable etcd.service
Created symlink from /etc/systemd/system/multi-user.target.wants/etcd.service to /usr/lib/systemd/system/etcd.service.
6.测试数据库功能
[root@node1 ~]# etcdctl set testdir/testkey0 1000
1000
[root@node1 ~]# etcdctl get testdir/testkey0
1000
[root@node1 ~]# etcdctl set b 123
123
[root@node1 ~]# etcdctl get b
1237.测试集群是否健康
# 测试集群健康[root@node1 ~]# etcdctl -C http://192.168.2.10:4001 cluster-health
member 8e9e05c52164694d is healthy: got healthy result from http://192.168.2.10:2379
cluster is healthy
[root@node1 ~]# etcdctl -C http://192.168.2.10:2379 cluster-health
member 8e9e05c52164694d is healthy: got healthy result from http://192.168.2.10:2379
cluster is healthy8.修改flannel的配置文件
[root@node1 ~]# vim /etc/sysconfig/flanneld
4 FLANNEL_ETCD_ENDPOINTS="http://192.168.2.10:2379"
[root@node1 ~]# cat /etc/sysconfig/flanneld
# Flanneld configuration options # etcd url location. Point this to the server where etcd runs
FLANNEL_ETCD_ENDPOINTS="http://192.168.2.10:2379"# etcd config key. This is the configuration key that flannel queries
# For address range assignment
FLANNEL_ETCD_PREFIX="/atomic.io/network" # 存储数据的位置# Any additional options that you want to pass
#FLANNEL_OPTIONS=""9.向数据库中存入网段信息
[root@node1 ~]# etcdctl mk /atomic.io/network/config '{ "Network" : "172.20.0.0/16" }'
{ "Network" : "172.20.0.0/16" }[root@node1 ~]# etcdctl get /atomic.io/network/config
{ "Network" : "172.20.0.0/16" }10.查看flannel0的ip地址
[root@node1 ~]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:a5:08:12 brd ff:ff:ff:ff:ff:ffinet 192.168.2.10/24 brd 192.168.2.255 scope global noprefixroute ens33valid_lft forever preferred_lft foreverinet6 fe80::7bef:aa24:508b:e09/64 scope link tentative dadfailed valid_lft forever preferred_lft foreverinet6 fe80::9d6d:f728:f4f1:6c5b/64 scope link tentative dadfailed valid_lft forever preferred_lft foreverinet6 fe80::f09d:7503:dea1:e7ab/64 scope link tentative dadfailed valid_lft forever preferred_lft forever
3: flannel0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500link/none inet 172.20.64.0/16 scope global flannel0valid_lft forever preferred_lft foreverinet6 fe80::3ac2:e60:225:e090/64 scope link flags 800 valid_lft forever preferred_lft forever
11.安装docker
# 执行docker脚本[root@node1 ~]# source docker.sh12.docker服务没有开启之前查看ip
# 启动docker服务前# 查看ip
[root@node1 ~]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:a5:08:12 brd ff:ff:ff:ff:ff:ffinet 192.168.2.10/24 brd 192.168.2.255 scope global noprefixroute ens33valid_lft forever preferred_lft foreverinet6 fe80::7bef:aa24:508b:e09/64 scope link tentative dadfailed valid_lft forever preferred_lft foreverinet6 fe80::9d6d:f728:f4f1:6c5b/64 scope link tentative dadfailed valid_lft forever preferred_lft foreverinet6 fe80::f09d:7503:dea1:e7ab/64 scope link tentative dadfailed valid_lft forever preferred_lft forever
3: flannel0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500link/none inet 172.20.64.0/16 scope global flannel0valid_lft forever preferred_lft foreverinet6 fe80::3ac2:e60:225:e090/64 scope link flags 800 valid_lft forever preferred_lft forever13.启动docker服务后，查看ip
# 启动docker服务
[root@node1 ~]# systemctl start docker# 查看ip，就有docker了
[root@node1 ~]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:a5:08:12 brd ff:ff:ff:ff:ff:ffinet 192.168.2.10/24 brd 192.168.2.255 scope global noprefixroute ens33valid_lft forever preferred_lft foreverinet6 fe80::7bef:aa24:508b:e09/64 scope link tentative dadfailed valid_lft forever preferred_lft foreverinet6 fe80::9d6d:f728:f4f1:6c5b/64 scope link tentative dadfailed valid_lft forever preferred_lft foreverinet6 fe80::f09d:7503:dea1:e7ab/64 scope link tentative dadfailed valid_lft forever preferred_lft forever
3: flannel0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500link/none inet 172.20.64.0/16 scope global flannel0valid_lft forever preferred_lft foreverinet6 fe80::3ac2:e60:225:e090/64 scope link flags 800 valid_lft forever preferred_lft forever
4: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default link/ether 02:42:35:91:9e:11 brd ff:ff:ff:ff:ff:ffinet 172.17.0.1/16 brd 172.17.255.255 scope global docker0valid_lft forever preferred_lft forever[root@node1 ~]# cat /run/flannel/subnet.env
FLANNEL_NETWORK=172.20.0.0/16
FLANNEL_SUBNET=172.20.64.1/24
FLANNEL_MTU=1472
FLANNEL_IPMASQ=false14.从配置好docker服务的主机复制一份daemon.json文件
# 从其他主机复制一份daemon.json[root@node1 ~]# scp root@192.168.2.30:/etc/docker/daemon.json /etc/docker
root@192.168.2.30's password:
daemon.json 100% 402 247.1KB/s 00:00
[root@node1 ~]# vim /etc/docker/daemon.json
{"registry-mirrors": ["https://do.nark.eu.org","https://dc.j8.work","https://docker.m.daocloud.io","https://dockerproxy.com","https://docker.mirrors.ustc.edu.cn","https://docker.nju.edu.cn"],"hosts": ["tcp://0.0.0.0:2375","unix:///var/run/docker.sock"],"insecure-registries":["http://192.168.2.30:5000"]
}15.docker不能重启，修改docker.service文件
[root@node1 ~]# vim /usr/lib/systemd/system/docker.service# 修改前ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock# 修改后ExecStart=/usr/bin/dockerd # 需要重新加载文件，才能重启
[root@node1 ~]# systemctl daemon-reload
[root@node1 ~]# systemctl restart docker.service 16.查看flannel子网ip
[root@node1 ~]# cat /run/flannel/subnet.env
FLANNEL_NETWORK=172.20.0.0/16
FLANNEL_SUBNET=172.20.64.1/24
FLANNEL_MTU=1472
FLANNEL_IPMASQ=false17.修改docker0的IP和flannel0的IP在同一个网段
# 修改添加桥ip和路由字节1472-1500[root@node1 ~]# vim /etc/docker/daemon.json {"registry-mirrors": ["https://do.nark.eu.org","https://dc.j8.work","https://docker.m.daocloud.io","https://dockerproxy.com","https://docker.mirrors.ustc.edu.cn","https://docker.nju.edu.cn"],"hosts": ["tcp://0.0.0.0:2375","unix:///var/run/docker.sock"],"insecure-registries":["http://192.168.2.30:5000"],"bip" : "172.20.64.1/24","mtu" : 1472
}# 重启启动docker服务
[root@node1 ~]# systemctl restart docker.service 18.验证
# 验证成功
# docker0的IP和flannel0的IP在同一个网段（172.20.64.0）
[root@node1 ~]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:a5:08:12 brd ff:ff:ff:ff:ff:ffinet 192.168.2.10/24 brd 192.168.2.255 scope global noprefixroute ens33valid_lft forever preferred_lft foreverinet6 fe80::7bef:aa24:508b:e09/64 scope link tentative dadfailed valid_lft forever preferred_lft foreverinet6 fe80::9d6d:f728:f4f1:6c5b/64 scope link tentative dadfailed valid_lft forever preferred_lft foreverinet6 fe80::f09d:7503:dea1:e7ab/64 scope link tentative dadfailed valid_lft forever preferred_lft forever
3: flannel0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500link/none inet 172.20.64.0/16 scope global flannel0valid_lft forever preferred_lft foreverinet6 fe80::3ac2:e60:225:e090/64 scope link flags 800 valid_lft forever preferred_lft forever
4: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1472 qdisc noqueue state DOWN group default link/ether 02:42:35:91:9e:11 brd ff:ff:ff:ff:ff:ffinet 172.20.64.1/24 brd 172.20.64.255 scope global docker0valid_lft forever preferred_lft forever19.拉取镜像测试docker的ip地址
# 拉取centos镜像
[root@node1 ~]# docker pull centos
Using default tag: latest
latest: Pulling from library/centos
a1d0c7532777: Pull complete
Digest: sha256:a27fd8080b517143cbbbab9dfb7c8571c40d67d534bbdee55bd6c473f432b177
Status: Downloaded newer image for centos:latest
docker.io/library/centos:latest
# 创建容器
[root@node1 ~]# docker run -it centos:latest /bin/bash# 退出不中断容器
[root@72ed0ee15de4 /]# [root@node1 ~]# # 查看容器的ip地址
[root@node1 ~]# docker inspect 72e | grep IPA"SecondaryIPAddresses": null,"IPAddress": "172.20.64.2","IPAMConfig": null,"IPAddress": "172.20.64.2",从控
node2
# 安装flannel
[root@node2 ~]# yum -y install flannel# 修改flannel配置文件
# 绑定node1的数据库
[root@node2 ~]# vim /etc/sysconfig/flanneld
4 FLANNEL_ETCD_ENDPOINTS="http://192.168.2.10:2379"# 查看修改后的flannel配置文件的内容
[root@node2 ~]# cat /etc/sysconfig/flanneld
# Flanneld configuration options # etcd url location. Point this to the server where etcd runs
FLANNEL_ETCD_ENDPOINTS="http://192.168.2.10:2379"# etcd config key. This is the configuration key that flannel queries
# For address range assignment
FLANNEL_ETCD_PREFIX="/atomic.io/network"# Any additional options that you want to pass
#FLANNEL_OPTIONS=""# 启动flannel服务
[root@node2 ~]# systemctl start flanneld.service
Job for flanneld.service failed because a timeout was exceeded. See "systemctl status flanneld.service" and "journalctl -xe" for details.# 如果启动失败，就关掉node1的防火墙
[root@node1 ~]# systemctl stop firewalld
[root@node1 ~]# setenforce 0# 成功启动flannel服务
[root@node2 ~]# systemctl start flanneld.service # 查看flannel0的ip地址（172.20.45.0）
[root@node2 ~]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:ef:db:fa brd ff:ff:ff:ff:ff:ffinet 192.168.2.11/24 brd 192.168.2.255 scope global noprefixroute ens33valid_lft forever preferred_lft foreverinet6 fe80::7bef:aa24:508b:e09/64 scope link noprefixroute valid_lft forever preferred_lft foreverinet6 fe80::9d6d:f728:f4f1:6c5b/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft foreverinet6 fe80::f09d:7503:dea1:e7ab/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever
3: flannel0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500link/none inet 172.20.45.0/16 scope global flannel0valid_lft forever preferred_lft foreverinet6 fe80::4dd7:31b5:677f:fd33/64 scope link flags 800 valid_lft forever preferred_lft forever
修改docker0的IP和flannel0为同一个网段
[root@node2 ~]# cat /run/flannel/subnet.env
FLANNEL_NETWORK=172.20.0.0/16
FLANNEL_SUBNET=172.20.45.1/24
FLANNEL_MTU=1472
FLANNEL_IPMASQ=false
[root@node2 ~]# vim /etc/docker/daemon.json
{"registry-mirrors": ["https://do.nark.eu.org","https://dc.j8.work","https://docker.m.daocloud.io","https://dockerproxy.com","https://docker.mirrors.ustc.edu.cn","https://docker.nju.edu.cn"],"hosts": ["tcp://0.0.0.0:2375","unix:///var/run/docker.sock"],"insecure-registries":["http://192.168.2.30:5000"],"bip" : "172.20.45.1/24","mtu" : 1472
}# 修改daemon.json文件，需要重启docker服务
# 启动失败
[root@node2 ~]# systemctl restart docker
Job for docker.service failed because the control process exited with error code. See "systemctl status docker.service" and "journalctl -xe" for details.# 修改docker.service配置文件
[root@node2 ~]# vim /usr/lib/systemd/system/docker.service# 删除dockerd后面的内容
13 ExecStart=/usr/bin/dockerd# 启动失败
[root@node2 ~]# systemctl restart docker
Warning: docker.service changed on disk. Run 'systemctl daemon-reload' to reload units.
Job for docker.service failed because start of the service was attempted too often. See "systemctl status docker.service" and "journalctl -xe" for details.
To force a start use "systemctl reset-failed docker.service" followed by "systemctl start docker.service" again.# 加载配置文件
[root@node2 ~]# systemctl daemon-reload# 成功启动docker服务
[root@node2 ~]# systemctl restart docker# 查看flannel0和docker0的ip地址，就会看到在同一个网段（172.20.45.0）
[root@node2 ~]# ip a s
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000link/ether 00:0c:29:ef:db:fa brd ff:ff:ff:ff:ff:ffinet 192.168.2.11/24 brd 192.168.2.255 scope global noprefixroute ens33valid_lft forever preferred_lft foreverinet6 fe80::7bef:aa24:508b:e09/64 scope link noprefixroute valid_lft forever preferred_lft foreverinet6 fe80::9d6d:f728:f4f1:6c5b/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft foreverinet6 fe80::f09d:7503:dea1:e7ab/64 scope link tentative noprefixroute dadfailed valid_lft forever preferred_lft forever
3: flannel0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500link/none inet 172.20.45.0/16 scope global flannel0valid_lft forever preferred_lft foreverinet6 fe80::4dd7:31b5:677f:fd33/64 scope link flags 800 valid_lft forever preferred_lft forever
4: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1472 qdisc noqueue state DOWN group default link/ether 02:42:0b:a4:c1:55 brd ff:ff:ff:ff:ff:ffinet 172.20.45.1/24 brd 172.20.45.255 scope global docker0valid_lft forever preferred_lft forever
[root@node2 ~]# docker pull centos
拉取镜像测试ip地址
# 拉取centos镜像
[root@node2 ~]# docker pull centos
Using default tag: latest
latest: Pulling from library/centos
a1d0c7532777: Pull complete
Digest: sha256:a27fd8080b517143cbbbab9dfb7c8571c40d67d534bbdee55bd6c473f432b177
Status: Downloaded newer image for centos:latest
docker.io/library/centos:latest# 创建容器
[root@node2 ~]# docker run -it centos:latest /bin/bash# 退出容器不中断
[root@d2d8a0756299 /]# [root@node2 ~]# # 查看容器ip地址，也和flannel0在同一个网段
[root@node2 ~]# docker inspect d2 | grep IPA"SecondaryIPAddresses": null,"IPAddress": "172.20.45.2","IPAMConfig": null,"IPAddress": "172.20.45.2",# 挂载容器终端，ping node1容器的地址：172.20.64.2
[root@node2 ~]# docker attach d2
[root@d2d8a0756299 /]# ping 172.20.64.2
PING 172.20.64.2 (172.20.64.2) 56(84) bytes of data.
64 bytes from 172.20.64.2: icmp_seq=1 ttl=60 time=2.51 ms
64 bytes from 172.20.64.2: icmp_seq=2 ttl=60 time=0.759 ms
^C
--- 172.20.64.2 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1002ms
rtt min/avg/max/mdev = 0.759/1.632/2.506/0.874 ms# 在node1上拉取镜像，创建容器，测试ip地址
[root@node1 ~]# docker run -it centos:latest /bin/bash
[root@72ed0ee15de4 /]# [root@node1 ~]#
[root@node1 ~]# docker inspect 72e | grep IPA"SecondaryIPAddresses": null,"IPAddress": "172.20.64.2","IPAMConfig": null,"IPAddress": "172.20.64.2",# 在node1上挂载容器的终端，ping node2容器的地址：172.20.45.2
[root@node1 ~]# docker attach 72e
[root@72ed0ee15de4 /]# ping 172.20.45.2
PING 172.20.45.2 (172.20.45.2) 56(84) bytes of data.
64 bytes from 172.20.45.2: icmp_seq=1 ttl=60 time=0.437 ms
64 bytes from 172.20.45.2: icmp_seq=2 ttl=60 time=0.845 ms
^C
--- 172.20.45.2 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 0.437/0.641/0.845/0.204 ms
node2步骤小结：
1.安装flannel
yum -y install flannel2.配置flannel 要访问的etcd数据库所在的位置
[root@node2 ~]# cat /etc/sysconfig/flanneld
# Flanneld configuration options # etcd url location. Point this to the server where etcd runs
FLANNEL_ETCD_ENDPOINTS="http://192.168.2.10:2379"# etcd config key. This is the configuration key that flannel queries
# For address range assignment
FLANNEL_ETCD_PREFIX="/atomic.io/network"# Any additional options that you want to pass
#FLANNEL_OPTIONS=""3.启动flannel
systemctl start flannel 4.查看flannel分配的ip网段
[root@node2 ~]# cat /run/flannel/subnet.env
FLANNEL_NETWORK=172.20.0.0/16
FLANNEL_SUBNET=172.20.45.1/24
FLANNEL_MTU=1472
FLANNEL_IPMASQ=false5.安装docker
# 执行docker.sh脚本6.将flannel分配的网段写入到daemon.json
[root@node2 ~]# vim /etc/docker/daemon.json
{"registry-mirrors": ["https://do.nark.eu.org","https://dc.j8.work","https://docker.m.daocloud.io","https://dockerproxy.com","https://docker.mirrors.ustc.edu.cn","https://docker.nju.edu.cn"],"hosts": ["tcp://0.0.0.0:2375","unix:///var/run/docker.sock"],"insecure-registries":["http://192.168.2.30:5000"],"bip" : "172.20.45.1/24","mtu" : 1472
}
7.重启docker 如果不能重启，就修改远程管理
[root@node2 ~]# systemctl restart docker
Job for docker.service failed because the control process exited with error code. See "systemctl status docker.service" and "journalctl -xe" for details.
[root@node2 ~]# vim /usr/lib/systemd/system/docker.service
# 删除dockerd后面的内容
13 ExecStart=/usr/bin/dockerd[root@node2 ~]# systemctl restart docker
Warning: docker.service changed on disk. Run 'systemctl daemon-reload' to reload units.
Job for docker.service failed because start of the service was attempted too often. See "systemctl status docker.service" and "journalctl -xe" for details.
To force a start use "systemctl reset-failed docker.service" followed by "systemctl start docker.service" again.
[root@node2 ~]# systemctl daemon-reload8.启动docker
[root@node2 ~]# systemctl restart docker9.拉取一个centos镜像
[root@node2 ~]# docker pull centos
Using default tag: latest
latest: Pulling from library/centos
a1d0c7532777: Pull complete
Digest: sha256:a27fd8080b517143cbbbab9dfb7c8571c40d67d534bbdee55bd6c473f432b177
Status: Downloaded newer image for centos:latest
docker.io/library/centos:latest10.ping node1中容器的ip地址
[root@node2 ~]# docker run -it centos:latest /bin/bash
[root@d2d8a0756299 /]# [root@node2 ~]#
[root@node2 ~]# docker inspect d2 | grep IPA"SecondaryIPAddresses": null,"IPAddress": "172.20.45.2","IPAMConfig": null,"IPAddress": "172.20.45.2",[root@node2 ~]# docker attach d2
[root@d2d8a0756299 /]# ping 172.20.64.2
PING 172.20.64.2 (172.20.64.2) 56(84) bytes of data.
64 bytes from 172.20.64.2: icmp_seq=1 ttl=60 time=2.51 ms
64 bytes from 172.20.64.2: icmp_seq=2 ttl=60 time=0.759 ms
^C
--- 172.20.64.2 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1002ms
rtt min/avg/max/mdev = 0.759/1.632/2.506/0.874 ms四、总结：工作原理
1.使用flannel为docker主机（宿主）分配网段2.网段的信息以及ip的信息保存在etcd数据库中3.当flannel开始运行的时候，会从etcd数据库中读取{"Network":"172.20.0.0/16"},随机为当前的主机添加一个flannel0网段172.20.64.04.配置docker的daemon文件，让docker0网卡变成和flannel0的网段一致，之后docker下创建的容器的ip就在flannel网段控制之内