Earlier we learned that when the docker installation is completed, three networks will be automatically created, bridge (the network to which the container is connected by default), none, host
host: The container will not virtualize its own network card, configure its own IP address, etc., but use the IP and port of the host machine
container: The created container will not create its own network card and configure its own IP, but will share the IP and port range with a specified container
none: This mode turns off the network function of the container
bridge: This mode will assign and set IP for each container, and connect the container to a docker0 virtual bridge, and communicate with the host through the docker0 bridge and iptables nat table configuration
After we install docker, we check the IP address of docker0
Create a new container and configure him with the IP address of the same network segment as docker0
[root@localhost ~]# docker run -itd --name test1 --network bridge --ip 172.17.0.100 centos:7 /bin/bash
98b29e7191b76909d6ccd95b29d4b17d91decee7e8da74320e7ebfb8906485fc
docker: Error response from daemon: user specified IP address is supported on user defined networks only.
#检查镜像[root@localhost ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
mysql new b43d6632e783 9 hours ago 10.1GB
centos 7 5e35e350aded 5 months ago 203MB
#检查容器[root@localhost ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
98b29e7191b7 centos:7 "/bin/bash" 2 minutes ago Created test1
86f87f283a50 mysql:new "init" 6 hours ago Up 6 hours 0.0.0.0:32776->3306/tcp mysql_server
#由上面可知，容器的创建并没有问题，接下来尝试启动容器[root@localhost ~]# docker start 98b29e7191b7
Error response from daemon: user specified IP address is supported on user defined networks only
Error: failed to start containers: 98b29e7191b7
#容器并没有启动成功，所以不能这样指定bridge模式的固定的IP地址
Next, customize the network fixed IP
[root@localhost ~]# docker rm 98b29e7191b7
98b29e7191b7
#删除刚刚的容器[root@localhost ~]# docker run -itd --name test1 --network bridge centos:7 /bin/bash
6bf95817ff0d0a43fa4d1bf97df32101347d364af25161025dd78dff9b536fda
[root@localhost ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
6bf95817ff0d centos:7 "/bin/bash" 6 seconds ago Up 4 seconds test1
86f87f283a50 mysql:new "init" 6 hours ago Up 6 hours 0.0.0.0:32776->3306/tcp mysql_server
[root@localhost ~]# docker exec -it 6bf95817ff0d /bin/bash[root@6bf95817ff0d /]# yum -y install net-tools[root@6bf95817ff0d /]# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.17.0.3 netmask 255.255.0.0 broadcast 172.17.255.255
ether 02:42:ac:11:00:03 txqueuelen 0 (Ethernet)
RX packets 5349 bytes 15213111 (14.5 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 3978 bytes 219357 (214.2 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
loop txqueuelen 1000 (Local Loopback)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
[root@6bf95817ff0d /]# ping 172.17.0.1
PING 172.17.0.1 (172.17.0.1) 56(84) bytes of data.
64 bytes from 172.17.0.1: icmp_seq=1 ttl=64 time=0.338 ms
64 bytes from 172.17.0.1: icmp_seq=2 ttl=64 time=0.112 ms
64 bytes from 172.17.0.1: icmp_seq=3 ttl=64 time=0.119 ms
^C
--- 172.17.0.1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2001ms
rtt min/avg/max/mdev = 0.112/0.189/0.338/0.106 ms
#尝试不指定容器的固定IP，并发现容器的地址为172.17.0.3[root@localhost ~]# docker network ls
NETWORK ID NAME DRIVER SCOPE
9ac53bd24af2 bridge bridge local
25ef346a7df8 host host local
9de3e1ea939c none null local
[root@localhost ~]# docker network create --subnet=172.18.0.0/16 mynetwork
aac45434a763e5c4588ce05aee36f628ecfe2b0cb9185270023c93e5c0962b4c
[root@localhost ~]# docker network ls
NETWORK ID NAME DRIVER SCOPE
9ac53bd24af2 bridge bridge local
25ef346a7df8 host host local
aac45434a763 mynetwork bridge local
9de3e1ea939c none null local
[root@localhost ~]# docker run -itd --name test2 --net mynetwork --ip=172.18.0.10 centos:7 /bin/bash
5f867fcc8d55ab4b9e7776dab43fac499ede9ac97145ef347eaef19d12f43557
[root@localhost ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
5f867fcc8d55 centos:7 "/bin/bash" 7 seconds ago Up 6 seconds test2
86f87f283a50 mysql:new "init" 7 hours ago Up 7 hours 0.0.0.0:32776->3306/tcp mysql_server
[root@localhost ~]# docker exec -it 5f867fcc8d55 /bin/bash[root@5f867fcc8d55 /]# yum -y install net-tools[root@5f867fcc8d55 /]# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.18.0.10 netmask 255.255.0.0 broadcast 172.18.255.255
ether 02:42:ac:12:00:0a txqueuelen 0 (Ethernet)
RX packets 5444 bytes 15219394 (14.5 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 4014 bytes 221367 (216.1 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
loop txqueuelen 1000 (Local Loopback)
RX packets 63 bytes 5759 (5.6 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 63 bytes 5759 (5.6 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
#可以看到，容器的IP地址就是自定义的地址。
