Docker容器的网络管理和网络隔离的实现

一、Docker网络的管理

1、Docker容器的方式

1）Docker访问外网

Docker容器连接到宿主机的Docker0网桥访问外网；默认自动将docker0网桥添加到docker容器中。

2）容器和容器之间通信
需要管理员创建网桥；将不同的容器连接到网桥上实现容器和容器之间相互访问。

3）外部网络访问容器
通过端口映射或者同步docker宿主机网络配置实现通信。

2、Docker容器网络通信的模式

1）bridge
默认容器访问外网通信使用；依赖docker0网桥。

2）none
需要给容器创建独立的网络命名空间；不会给创建的容器配置TCP/IP信息。

3）container
容器和容器通信使用；容器需要共享容器名称空间，通过共享容器名称空间实现不同容器通信。

4）host
容器内部网络和宿主机保持同步。

3、配置bridge网络通信模式

[root@centos01 yum.repos.d]# wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo 
       
[root@centos01 ~]# yum -y install docker   
[root@centos01 ~]# systemctl start docker    
[root@centos01 ~]# systemctl enable docker   
[root@centos01 ~]# echo "net.ipv4.ip_forward = 1" >> /etc/sysctl.conf  
[root@centos01 ~]# sysctl -p 
net.ipv4.ip_forward = 1
[root@centos01 ~]# docker pull hub.c.163.com/public/centos:7.2-tools 
[root@centos01 ~]# docker images 
REPOSITORY          TAG         IMAGE ID      CREATED       SIZE
hub.c.163.com/public/centos  7.2-tools      4a4618db62b9    3 years ago     515 MB
[root@centos01 ~]# docker run -d --net=bridge --name centos7.201 hub.c.163.com/public/centos:7.2-tools  
      
b308fb5c097fd455073f2f4a280d2660e6943fe1a62d6409e8ebcd3b86469438
[root@centos01 ~]# docker ps 
CONTAINER ID    IMAGE                  COMMAND         CREATED       STATUS       PORTS        NAMES
b308fb5c097f    hub.c.163.com/public/centos:7.2-tools  "/usr/bin/supervisord"  20 seconds ago   Up 19 seconds    22/tcp       centos7.201
[root@centos01 ~]# ifconfig  
docker0: flags=4163 mtu 1500
    inet 172.17.0.1 netmask 255.255.0.0 broadcast 0.0.0.0
[root@centos01 ~]# docker exec -it centos7.201 /bin/bash 
[root@b308fb5c097f /]# ifconfig  
eth0: flags=4163 mtu 1500
    inet 172.17.0.2 netmask 255.255.0.0 broadcast 0.0.0.0
[root@b308fb5c097f /]# ping www.baidu.com 
PING www.a.shifen.com (39.156.66.18) 56(84) bytes of data.
64 bytes from 39.156.66.18: icmp_seq=1 ttl=50 time=18.4 ms
64 bytes from 39.156.66.18: icmp_seq=2 ttl=50 time=18.3 ms
64 bytes from 39.156.66.18: icmp_seq=3 ttl=50 time=16.9 ms
[root@b308fb5c097f /]# ping 192.168.100.10  
PING 192.168.100.10 (192.168.100.10) 56(84) bytes of data.
64 bytes from 192.168.100.10: icmp_seq=1 ttl=64 time=0.043 ms
64 bytes from 192.168.100.10: icmp_seq=2 ttl=64 time=0.086 ms
64 bytes from 192.168.100.10: icmp_seq=3 ttl=64 time=0.150 ms

4、配置none网络通信模式

[root@centos01 ~]# docker run -d --net=none --name centos7.202 hub.c.163.com/public/centos:7.2-tools  
      
e2c4837d67818e7ef4d7cedf964db21d98cabb594d12091d7f69da4e8fb3f30f
[root@centos01 ~]# docker ps 
CONTAINER ID    IMAGE                  COMMAND         CREATED       STATUS       PORTS        NAMES
e2c4837d6781    hub.c.163.com/public/centos:7.2-tools  "/usr/bin/supervisord"  57 seconds ago   Up 56 seconds              centos7.202
b308fb5c097f    hub.c.163.com/public/centos:7.2-tools  "/usr/bin/supervisord"  7 minutes ago    Up 7 minutes    22/tcp       centos7.201
[root@centos01 ~]# docker exec -it centos7.202 /bin/bash 
[root@e2c4837d6781 /]# ifconfig  
lo: flags=73 mtu 65536
    inet 127.0.0.1 netmask 255.0.0.0
[root@e2c4837d6781 /]# ping www.baidu.com 
ping: unknown host www.baidu.com
[root@e2c4837d6781 /]# 
[root@e2c4837d6781 /]# ping 192.168.100.10 
connect: Network is unreachable

5、配置host网络通信模式

[root@centos01 ~]# docker run -d --net=host --name centos7.203 -v /data1 hub.c.163.com/public/centos:7.2-tools  
    
2911358be486720c4ee93c8de22cd77301236f48c5baf22ea63bb3c54450032e
[root@centos01 ~]# ls /var/lib/docker/volumes/ 
dc755f3b6036f167471435629918d06264e1c2c6a8b175426fa80da36143a87e metadata.db
[root@centos01 ~]# docker ps 
CONTAINER ID    IMAGE                  COMMAND         CREATED       STATUS       PORTS        NAMES
2911358be486    hub.c.163.com/public/centos:7.2-tools  "/usr/bin/supervisord"  About a minute ago  Up About a minute            centos7.203
e2c4837d6781    hub.c.163.com/public/centos:7.2-tools  "/usr/bin/supervisord"  15 minutes ago    Up 15 minutes              centos7.202
b308fb5c097f    hub.c.163.com/public/centos:7.2-tools  "/usr/bin/supervisord"  21 minutes ago    Up 21 minutes    22/tcp       centos7.201
[root@centos01 ~]# docker exec -it centos7.203 /bin/bash 
[root@centos01 /]# ifconfig  
docker0: flags=4163 mtu 1500
    inet 172.17.0.1 netmask 255.255.0.0 broadcast 0.0.0.0

ens32: flags=4163 mtu 1500
    inet 192.168.100.10 netmask 255.255.255.0 broadcast 192.168.100.255

ens34: flags=4163 mtu 1500
    inet 192.168.0.126 netmask 255.255.255.0 broadcast 192.168.0.255

lo: flags=73 mtu 65536
    inet 127.0.0.1 netmask 255.0.0.0

vethc39178a: flags=4163 mtu 1500
    inet6 fe80::7c4b:a6ff:fe1c:a37f prefixlen 64 scopeid 0x20

virbr0: flags=4099 mtu 1500
    inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255
[root@centos01 ~]# docker exec -it centos7.203 /bin/bash  
[root@centos01 /]# ping www.baidu.com  
PING www.a.shifen.com (39.156.66.14) 56(84) bytes of data.
64 bytes from 39.156.66.14: icmp_seq=1 ttl=51 time=20.0 ms
64 bytes from 39.156.66.14: icmp_seq=2 ttl=51 time=19.1 ms
64 bytes from 39.156.66.14: icmp_seq=3 ttl=51 time=15.9 ms
[root@centos01 /]# ping 192.168.100.10  
PING 192.168.100.10 (192.168.100.10) 56(84) bytes of data.
64 bytes from 192.168.100.10: icmp_seq=1 ttl=64 time=0.020 ms
64 bytes from 192.168.100.10: icmp_seq=2 ttl=64 time=0.060 ms
64 bytes from 192.168.100.10: icmp_seq=3 ttl=64 time=0.030 ms
     
[root@centos01 ~]# cp /mnt/nginx-1.6.0.tar.gz ./  
[root@centos01 ~]# ls 
anaconda-ks.cfg initial-setup-ks.cfg nginx-1.6.0.tar.gz
[root@centos01 ~]# cp nginx-1.6.0.tar.gz /var/lib/docker/volumes/dc755f3b6036f167471435629918d06264e1c2c6a8b175426fa80da36143a87e/_data/ 
    
[root@centos01 ~]# docker exec -it centos7.203 /bin/bash  
[root@centos01 /]# ls
anaconda-post.log bin data1 dev etc home lib lib64 lost+found media mnt opt proc root run sbin srv sys tmp usr var
[root@centos01 /]# cd data1/  
[root@centos01 data1]# ls  
nginx-1.6.0.tar.gz
[root@centos01 /]# yum -y install pcre-devel zlib-devel  
[root@centos01 /]# useradd -M -s /sbin/nologin nginx  
[root@centos01 /]# tar zxvf /data1/nginx-1.6.0.tar.gz -C /usr/src/  
[root@centos01 /]#yum -y install gcc pcre-devel zlib-devel make 
[root@centos01 /]# cd /usr/src/nginx-1.6.0/
[root@centos01 nginx-1.6.0]# ./configure --prefix=/usr/local/nginx --user=nginx --with-http_stub_status_module && make && make install  
        
[root@centos01 nginx-1.6.0]# ln -s /usr/local/nginx/sbin/nginx /usr/local/sbin/ 
[root@centos01 nginx-1.6.0]# echo "www.docker.nginx.com" > /usr/local/nginx/html/index.html      
           
[root@centos01 nginx-1.6.0]# ln -s /usr/local/nginx/sbin/nginx /usr/local/sbin/ 
     
[root@centos01 nginx-1.6.0]# netstat -anptu | grep nginx 
tcp    0   0 0.0.0.0:80       0.0.0.0:*        LISTEN   6268/nginx: master 
[root@centos01 ~]# curl http://192.168.100.10 
www.docker.nginx.com
[root@centos01 nginx-1.6.0]# cat /usr/local/nginx/logs/access.log  
     
192.168.100.10 - - [12/May/2020:21:42:47 +0800] "GET / HTTP/1.1" 200 21 "-" "curl/7.29.0"

6、配置docker0网卡参数

[root@centos01 ~]# ifconfig  
docker0: flags=4163 mtu 1500
    inet 172.17.0.1 netmask 255.255.0.0 broadcast 0.0.0.0
[root@centos01 ~]# systemctl stop docker  
[root@centos01 ~]# ip link set dev docker0 down  
[root@centos01 ~]# brctl delbr docker0  
[root@centos01 ~]# brctl addbr docker0  
[root@centos01 ~]# ip addr add 192.168.20.1/24 dev dokcer0 
[root@centos01 ~]# ip link set dev docker0 up  
[root@centos01 ~]# vim /etc/docker/daemon.json  
    
{"registry-mirrors":["https://6kx4zyno.mirror.aliyuncs.com"]}
{"bip":"192.168.20.1/24"}  
[root@centos01 ~]# systemctl start docker  
[root@centos01 ~]# ifconfig  
docker0: flags=4163 mtu 1500
    inet 192.168.20.1 netmask 255.255.255.0 broadcast 0.0.0.0
[root@centos01 ~]# docker run -it -d --name centos7.2v1 hub.c.163.com/public/centos:7.2-tools  
d0b5392e60cef37f3c44d79a9fb73916720cfc44faa7b73862bee05fb2d6ce7b
[root@centos01 ~]# docker exec -it centos7.2v1 /bin/bash 
[root@d0b5392e60ce /]# ifconfig  
eth0: flags=4163 mtu 1500
    inet 192.168.20.2 netmask 255.255.255.0 broadcast 0.0.0.0

二、Docker网络隔离

1、Docker网络隔离原理

需要管理创建网络空间名称；将不同的容器加载到不同的网络空间名称中实现隔离；默认不配置网络隔离默认给容器分配的docker0网络空间名称。

2、Docker容器自带的网络空间名称类型

bridge：容器桥接到docker0网桥上；
host：容器同步docker宿主机的网络配置信息；
none：不创建网络，docker容器不需要配置TCP/IP信息；

3、配置Docker网络名称空间隔离

[root@centos01 ~]# docker network ls  
NETWORK ID     NAME        DRIVER       SCOPE
8bb953004416    bridge       bridge       local
2c18234cad82    host        host        local
67860e823c36    none        null        local
[root@centos01 ~]# docker network create -d bridge liyanxin 
0c69de4672ec173dc4c60b19e0bf93b361f45a804859f7bc2105d85ca83b1169
[root@centos01 ~]# docker network create -d bridge gongsunli  
35687468c9034262173a96e9c23e045cbb8b7ffa6648fc84e015504740815001
[root@centos01 ~]# ifconfig  
br-0c69de4672ec: flags=4099 mtu 1500
    inet 172.18.0.1 netmask 255.255.0.0 broadcast 0.0.0.0

br-35687468c903: flags=4099 mtu 1500
    inet 172.19.0.1 netmask 255.255.0.0 broadcast 0.0.0.0
[root@centos01 ~]# docker run -it -d --name centos6.701 --network=liyanxin hub.c.163.com/public/centos:6.7-tools  
     
b85a2d8419a98756369ddc3b78247d3d42c178e8e563a936fe973f2f6611f951
[root@centos01 ~]# docker exec -it centos6.701 /bin/bash  
[root@b85a2d8419a9 /]# ifconfig  
eth0   Link encap:Ethernet HWaddr 02:42:AC:12:00:02 
     inet addr:172.18.0.2 Bcast:0.0.0.0 Mask:255.255.0.0
[root@centos01 ~]# docker run -it -d --name centos6.702 --network=gongsunli hub.c.163.com/public/centos:6.7-tools  
   
9af0fb7b85af3270f3c7c44b62438f436b22289ac0a7604d6ed522604b7b185f
[root@centos01 ~]# docker exec -it centos6.702 /bin/bash 
[root@9af0fb7b85af /]# ifconfig  
eth0   Link encap:Ethernet HWaddr 02:42:AC:13:00:02 
     inet addr:172.19.0.2 Bcast:0.0.0.0 Mask:255.255.0.0

三、配置网桥实现网络隔离

1、配置网桥实现网络隔离的目的

实现Docker宿主机的容器跨Docker宿主机的容器通信使用。

2、配置网桥实现网络隔离原理
将物理网卡桥接到创建的网桥网卡上；给网桥网卡配置IP地址；创建容器加载网桥网卡实现；docker宿主机容器跨docker宿主机容器通信；管理员管理docker宿主机通过网桥网卡进行远程管理

3、配置docker网桥实现网络隔离

[root@centos01 ~]# vim /etc/sysconfig/network-scripts/ifcfg-ens32 
     
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=static
DEFROUTE=yes
NAME=ens32
DEVICE=ens32
ONBOOT=yes
BRIDGE=br0  
[root@centos01 ~]# cp /etc/sysconfig/network-scripts/ifcfg-ens32 /etc/sysconfig/network-scripts/ifcfg-br0  
     
[root@centos01 ~]# vim /etc/sysconfig/network-scripts/ifcfg-br0 
TYPE=Bridge  
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=static
DEFROUTE=yes
NAME=br0   
DEVICE=br0  
ONBOOT=yes
IPADDR=192.168.100.10  
NETMASK=255.255.255.0 
[root@centos01 ~]# systemctl restart network  
[root@centos01 ~]# ifconfig  
br0: flags=4163 mtu 1500
    inet 192.168.100.10 netmask 255.255.255.0 broadcast 192.168.100.255

br-0c69de4672ec: flags=4163 mtu 1500
    inet 172.18.0.1 netmask 255.255.0.0 broadcast 0.0.0.0

br-35687468c903: flags=4163 mtu 1500
    inet 172.19.0.1 netmask 255.255.0.0 broadcast 0.0.0.0

docker0: flags=4099 mtu 1500
    inet 172.17.0.1 netmask 255.255.0.0 broadcast 0.0.0.0

ens32: flags=4163 mtu 1500
    ether 00:0c:29:18:d3:26 txqueuelen 1000 (Ethernet)

ens34: flags=4163 mtu 1500
    inet6 fe80::4ad2:dd37:4341:5d8e prefixlen 64 scopeid 0x20

lo: flags=73 mtu 65536
    inet 127.0.0.1 netmask 255.0.0.0

veth7b0bb5f: flags=4163 mtu 1500
    inet6 fe80::ccd3:86ff:fee6:5725 prefixlen 64 scopeid 0x20

veth7e0f471: flags=4163 mtu 1500
    inet6 fe80::684c:fdff:fe13:b436 prefixlen 64 scopeid 0x20

virbr0: flags=4099 mtu 1500
    inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255
[root@centos01 ~]# yum -y install git  
[root@centos01 ~]# git clone https://github.com/jpetazzo/pipework
      
[root@centos01 ~]# cp pipework/pipework /usr/local/bin/  
[root@centos01 ~]# chmod +x /usr/local/bin/pipework  
[root@centos01 ~]# docker run -d --name centos6.703 --network=none hub.c.163.com/public/centos:6.7-tools  
       
adea0ad48bdde947ec595382d96cba06eb6522ec046e9b3c7bfcb1edb5c84545
[root@centos01 ~]# pipework br0 centos6.703 192.168.100.101/24  
          
[root@centos01 ~]# docker exec -it centos6.703 /bin/bash  
[root@adea0ad48bdd /]# ifconfig  
eth1   Link encap:Ethernet HWaddr FA:3A:9D:ED:C0:FF 
     inet addr:192.168.100.101 Bcast:192.168.100.255 Mask:255.255.255.0
[root@adea0ad48bdd /]# ping 192.168.100.10
PING 192.168.100.10 (192.168.100.10) 56(84) bytes of data.
64 bytes from 192.168.100.10: icmp_seq=1 ttl=64 time=0.100 ms
64 bytes from 192.168.100.10: icmp_seq=2 ttl=64 time=0.097 ms
64 bytes from 192.168.100.10: icmp_seq=3 ttl=64 time=0.039 ms

4、配置docker宿主机容器和docker宿主机容器通信

[root@centos02 ~]# ping www.baidu.com 
PING www.a.shifen.com (39.156.66.18) 56(84) bytes of data.
64 bytes from 39.156.66.18 (39.156.66.18): icmp_seq=1 ttl=51 time=19.5 ms
64 bytes from 39.156.66.18 (39.156.66.18): icmp_seq=2 ttl=51 time=17.3 ms
64 bytes from 39.156.66.18 (39.156.66.18): icmp_seq=3 ttl=51 time=18.1 ms
[root@centos02 ~]# cd /etc/yum.repos.d/
[root@centos02 yum.repos.d]# ls
local.repo
[root@centos02 yum.repos.d]# wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo 
    
[root@centos02 ~]# yum install docker -y  
[root@centos02 ~]# systemctl start docker   
[root@centos02 ~]# systemctl enable docker  
[root@centos02 ~]# docker pull hub.c.163.com/public/centos:6.7-tools  
[root@centos02 ~]# docker images  
REPOSITORY          TAG         IMAGE ID      CREATED       SIZE
hub.c.163.com/public/centos  6.7-tools      b2ab0ed558bb    3 years ago     602 MB
[root@centos02 ~]# vim /etc/sysconfig/network-scripts/ifcfg-ens32  
       
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=static
DEFROUTE=yes
NAME=ens32
DEVICE=ens32
ONBOOT=yes
BRIDGE=br0  
[root@centos02 ~]# cp /etc/sysconfig/network-scripts/ifcfg-ens32 /etc/sysconfig/network-scripts/ifcfg-br0     
[root@centos02 ~]# vim /etc/sysconfig/network-scripts/ifcfg-br0 
TYPE=Bridge  
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=static
DEFROUTE=yes
NAME=br0  
DEVICE=br0  
ONBOOT=yes
IPADDR=192.168.100.20  
NETMASK=255.255.255.0
[root@centos02 ~]# systemctl restart network  
[root@centos02 ~]# ifconfig  
br0: flags=4163 mtu 1500
    inet 192.168.100.20 netmask 255.255.255.0 broadcast 192.168.100.255

docker0: flags=4099 mtu 1500
    inet 172.17.0.1 netmask 255.255.0.0 broadcast 0.0.0.0

ens32: flags=4163 mtu 1500
    ether 00:0c:29:97:5c:9f txqueuelen 1000 (Ethernet)

ens34: flags=4163 mtu 1500
    inet 192.168.0.104 netmask 255.255.255.0 broadcast 192.168.0.255

lo: flags=73 mtu 65536
    inet 127.0.0.1 netmask 255.0.0.0

virbr0: flags=4099 mtu 1500
    inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255
[root@centos02 ~]# yum -y install git  
[root@centos02 ~]# git clone https://github.com/jpetazzo/pipework  
     
[root@centos02 ~]# cp pipework/pipework /usr/local/bin/  
[root@centos02 ~]# chmod +x /usr/local/bin/pipework  
[root@centos02 ~]# docker run -d --name centos6.7 --network=none hub.c.163.com/public/centos:6.7-tools  
abec0a6bd3822a2fd702dc44d1cf3043648aadd1a661e577c23701e30ee9df7a
[root@centos02 ~]# pipework br0 centos6.7 192.168.100.102/24  
     
[root@centos02 ~]# docker exec -it centos6.7 /bin/bash  
[root@abec0a6bd382 /]# ifconfig  
eth1   Link encap:Ethernet HWaddr EE:01:B7:99:90:1C 
     inet addr:192.168.100.102 Bcast:192.168.100.255 Mask:255.255.255.0
[root@abec0a6bd382 /]# ping 192.168.100.101  
PING 192.168.100.101 (192.168.100.101) 56(84) bytes of data.
64 bytes from 192.168.100.101: icmp_seq=1 ttl=64 time=0.660 ms
64 bytes from 192.168.100.101: icmp_seq=2 ttl=64 time=0.865 ms
64 bytes from 192.168.100.101: icmp_seq=3 ttl=64 time=0.382 ms
[root@abec0a6bd382 /]# ping 192.168.100.10  
PING 192.168.100.10 (192.168.100.10) 56(84) bytes of data.
64 bytes from 192.168.100.10: icmp_seq=1 ttl=64 time=0.632 ms
64 bytes from 192.168.100.10: icmp_seq=2 ttl=64 time=0.732 ms
64 bytes from 192.168.100.10: icmp_seq=3 ttl=64 time=0.796 ms
[root@abec0a6bd382 /]# ping 192.168.100.20  
PING 192.168.100.20 (192.168.100.20) 56(84) bytes of data.
64 bytes from 192.168.100.20: icmp_seq=1 ttl=64 time=0.144 ms
64 bytes from 192.168.100.20: icmp_seq=2 ttl=64 time=0.094 ms
64 bytes from 192.168.100.20: icmp_seq=3 ttl=64 time=0.043 ms