創(chuàng)建兩個容器
$ docker container run -d --rm --name box1 busybox /bin/sh -c "while true; do sleep 3600; done"
$ docker container run -d --rm --name box2 busybox /bin/sh -c "while true; do sleep 3600; done"
$ docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
4f3303c84e53 busybox "/bin/sh -c 'while t…" 49 minutes ago Up 49 minutes box2
03494b034694 busybox "/bin/sh -c 'while t…" 49 minutes ago Up 49 minutes box1
容器間通信
兩個容器都連接到了一個叫 docker0
的Linux bridge
上
$ docker network ls
NETWORK ID NAME DRIVER SCOPE
1847e179a316 bridge bridge local
a647a4ad0b4f host host local
fbd81b56c009 none null local
$ docker network inspect bridge
[
{
"Name": "bridge",
"Id": "1847e179a316ee5219c951c2c21cf2c787d431d1ffb3ef621b8f0d1edd197b24",
"Created": "2021-07-01T15:28:09.265408946Z",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": null,
"Config": [
{
"Subnet": "172.17.0.0/16",
"Gateway": "172.17.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"03494b034694982fa085cc4052b6c7b8b9c046f9d5f85f30e3a9e716fad20741": {
"Name": "box1",
"EndpointID": "072160448becebb7c9c333dce9bbdf7601a92b1d3e7a5820b8b35976cf4fd6ff",
"MacAddress": "02:42:ac:11:00:02",
"IPv4Address": "172.17.0.2/16",
"IPv6Address": ""
},
"4f3303c84e5391ea37db664fd08683b01decdadae636aaa1bfd7bb9669cbd8de": {
"Name": "box2",
"EndpointID": "4cf0f635d4273066acd3075ec775e6fa405034f94b88c1bcacdaae847612f2c5",
"MacAddress": "02:42:ac:11:00:03",
"IPv4Address": "172.17.0.3/16",
"IPv6Address": ""
}
},
"Options": {
"com.docker.network.bridge.default_bridge": "true",
"com.docker.network.bridge.enable_icc": "true",
"com.docker.network.bridge.enable_ip_masquerade": "true",
"com.docker.network.bridge.host_binding_ipv4": "0.0.0.0",
"com.docker.network.bridge.name": "docker0",
"com.docker.network.driver.mtu": "1500"
},
"Labels": {}
}
]
Note
brctl
使用前需要安裝, 對于CentOS, 可以通過sudo yum install -y bridge-utils
安裝;對于Ubuntu, 可以通過sudo apt-get install -y bridge-utils
$ brctl show
bridge name bridge id STP enabled interfaces
docker0 8000.0242759468cf no veth8c9bb82
vethd8f9afb
容器對外通信
查看路由
$ ip route
default via 10.0.2.2 dev eth0 proto dhcp metric 100
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15 metric 100
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1
192.168.200.0/24 dev eth1 proto kernel scope link src 192.168.200.10 metric 101
iptable 轉(zhuǎn)發(fā)規(guī)則
$ sudo iptables --list -t nat
Chain PREROUTING (policy ACCEPT)
target prot opt source destination
DOCKER all -- anywhere anywhere ADDRTYPE match dst-type LOCAL
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
DOCKER all -- anywhere !loopback/8 ADDRTYPE match dst-type LOCAL
Chain POSTROUTING (policy ACCEPT)
target prot opt source destination
MASQUERADE all -- 172.17.0.0/16 anywhere
Chain DOCKER (2 references)
target prot opt source destination
RETURN all -- anywhere anywhere
端口轉(zhuǎn)發(fā)
創(chuàng)建容器
$ docker container run -d --rm --name web -p 8080:80 nginx
$ docker container inspect --format '{{.NetworkSettings.IPAddress}}' web
$ docker container run -d --rm --name client busybox /bin/sh -c "while true; do sleep 3600; done"
$ docker container inspect --format '{{.NetworkSettings.IPAddress}}' client
$ docker container exec -it client wget http://172.17.0.2
查看iptables的端口轉(zhuǎn)發(fā)規(guī)則
[vagrant@docker-host1 ~]$ sudo iptables -t nat -nvxL
Chain PREROUTING (policy ACCEPT 10 packets, 1961 bytes)
pkts bytes target prot opt in out source destination
1 52 DOCKER all -- * * 0.0.0.0/0 0.0.0.0/0 ADDRTYPE match dst-type LOCAL
Chain INPUT (policy ACCEPT 9 packets, 1901 bytes)
pkts bytes target prot opt in out source destination
Chain OUTPUT (policy ACCEPT 2 packets, 120 bytes)
pkts bytes target prot opt in out source destination
0 0 DOCKER all -- * * 0.0.0.0/0 !127.0.0.0/8 ADDRTYPE match dst-type LOCAL
Chain POSTROUTING (policy ACCEPT 4 packets, 232 bytes)
pkts bytes target prot opt in out source destination
3 202 MASQUERADE all -- * !docker0 172.17.0.0/16 0.0.0.0/0
0 0 MASQUERADE tcp -- * * 172.17.0.2 172.17.0.2 tcp dpt:80
Chain DOCKER (2 references)
pkts bytes target prot opt in out source destination
0 0 RETURN all -- docker0 * 0.0.0.0/0 0.0.0.0/0
1 52 DNAT tcp -- !docker0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:8080 to:172.17.0.2:80