Docker Networking
Bridge network tutorial
$ docker network ls
NETWORK ID NAME DRIVER SCOPE
b74243bcc862 bridge bridge local
0f298ef4d3d6 host host local
7309c4c965e1 none null local
$ docker run -dit --name alpine1 alpine ash (1)
$ docker run -dit --name alpine2 alpine ash
$ docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
d020aaad68f0 alpine "ash" 10 minutes ago Up 10 minutes alpine2
7120f13e9afa alpine "ash" 11 minutes ago Up 11 minutes alpine1
$ docker network inspect bridge
[
{
"Name": "bridge",
"Id": "b74243bcc862375472d71f3ad66cbaa534e67c57c1251573effc8c88768a63b5",
"Created": "2019-04-10T15:20:57.663187656Z",
"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": {
"7120f13e9afa166e5280522fe34db9e72898b0e4b920c3718897bae45a7d2b72": {
"Name": "alpine1",
"EndpointID": "c1000f97c3ed9aa809042f7326545658875720715fcbce1cfff036f41d11e6be",
"MacAddress": "02:42:ac:11:00:02",
"IPv4Address": "172.17.0.2/16",
"IPv6Address": ""
},
"d020aaad68f029279d010df6baa41cba9c12162ef54d1b2e7eb69973567d8608": {
"Name": "alpine2",
"EndpointID": "7f9ad65a0a486e40e408dcc4a5a18932201266bf93bdc7c16c31222acc2c4473",
"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": {}
}
]
$ docker attach alpine1 (2)
# ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
4: eth0@if5: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue state UP
link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.2/16 brd 172.17.255.255 scope global eth0 (3)
valid_lft forever preferred_lft forever
# ping -c 2 172.17.0.3
// It's OK.
# ping -c 2 alpine2
ping: bad address 'alpine2'
$ docker container stop alpine1 alpine2
$ docker container rm alpine1 alpine2| 1 | -dit 到底是啥意思？运行完为啥没有退出？ |
| 2 | docker attach 是啥意思？ |
| 3 | 172.17.0.2 is the same address shown for alpine1 in the previous step. |
The default bridge network is not recommended for production.
$ docker network create --driver bridge alpine-net
$ docker network ls
NETWORK ID NAME DRIVER SCOPE
86c5ff0ae820 alpine-net bridge local
b74243bcc862 bridge bridge local
0f298ef4d3d6 host host local
7309c4c965e1 none null local
$ docker network inspect alpine-net
[
{
"Name": "alpine-net",
"Id": "86c5ff0ae82020389010703c8b7100dd1039d48163d76990e5dca057abbf027d",
"Created": "2019-04-10T15:45:37.052390658Z",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "172.18.0.0/16",
"Gateway": "172.18.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {},
"Options": {},
"Labels": {}
}
]
$ docker run -dit --name alpine1 --network alpine-net alpine ash
$ docker run -dit --name alpine2 --network alpine-net alpine ash
$ docker run -dit --name alpine3 alpine ash
$ docker run -dit --name alpine4 --network alpine-net alpine ash
$ docker network connect bridge alpine4 (1)
$ docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
29af7534f104 alpine "ash" About a minute ago Up About a minute alpine4
02c261c06e20 alpine "ash" About a minute ago Up About a minute alpine3
19b476579a47 alpine "ash" About a minute ago Up About a minute alpine2
6f806296de0a alpine "ash" About a minute ago Up About a minute alpine1
$ docker network inspect bridge
[
{
"Name": "bridge",
"Id": "b74243bcc862375472d71f3ad66cbaa534e67c57c1251573effc8c88768a63b5",
"Created": "2019-04-10T15:20:57.663187656Z",
"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": {
"02c261c06e20a00afe4d7ce9575e4913997a6eca45715804cfacc330a161cdc3": {
"Name": "alpine3",
"EndpointID": "9d29e03c065a1fbea419af7119c3938ec05d3e89ffcaa5cb2d098f12f2bcc4ef",
"MacAddress": "02:42:ac:11:00:02",
"IPv4Address": "172.17.0.2/16",
"IPv6Address": ""
},
"29af7534f10428bb0e42a4822fb1348d0e104dc1289556a12a27d49a86cde7ed": {
"Name": "alpine4", (1)
"EndpointID": "22e1090dcee4161ead04ba070372829afe9ee5dbe4380fe37fcd4de802675a6c",
"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": {}
}
]
$ docker network inspect alpine-net
[
{
"Name": "alpine-net",
"Id": "86c5ff0ae82020389010703c8b7100dd1039d48163d76990e5dca057abbf027d",
"Created": "2019-04-10T15:45:37.052390658Z",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "172.18.0.0/16",
"Gateway": "172.18.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"19b476579a47038a42e9d429bd7b04c5e347737870c322d460b9a1b410a8d003": {
"Name": "alpine2",
"EndpointID": "14f9c793c748e572104b66fca91658f5e78b15713edfd8b553e71ceb7d580a55",
"MacAddress": "02:42:ac:12:00:03",
"IPv4Address": "172.18.0.3/16",
"IPv6Address": ""
},
"29af7534f10428bb0e42a4822fb1348d0e104dc1289556a12a27d49a86cde7ed": {
"Name": "alpine4", (2)
"EndpointID": "536b2c3c83c0e0c0c9e5f3569cce1ed3eb92dde9b5f3dfefec7e2350bebe1458",
"MacAddress": "02:42:ac:12:00:04",
"IPv4Address": "172.18.0.4/16",
"IPv6Address": ""
},
"6f806296de0a2bbd3d93d0d6feaf8a91ecebb73e9ef9eff31c9da518e734a874": {
"Name": "alpine1",
"EndpointID": "6232bff81af9df498487df2247eba718e91fa6870c70b0d1e013fd9caef54493",
"MacAddress": "02:42:ac:12:00:02",
"IPv4Address": "172.18.0.2/16",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {}
}
]
$ docker container attach alpine1
/ # ping -c 2 alpine2
PING alpine2 (172.18.0.3): 56 data bytes
64 bytes from 172.18.0.3: seq=0 ttl=64 time=0.108 ms
64 bytes from 172.18.0.3: seq=1 ttl=64 time=0.093 ms
--- alpine2 ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 0.093/0.100/0.108 ms
/ # ping -c 2 alpine4
PING alpine4 (172.18.0.4): 56 data bytes
64 bytes from 172.18.0.4: seq=0 ttl=64 time=0.103 ms
64 bytes from 172.18.0.4: seq=1 ttl=64 time=0.093 ms
--- alpine4 ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 0.093/0.098/0.103 ms
/ # ping -c 2 alpine1
PING alpine1 (172.18.0.2): 56 data bytes
64 bytes from 172.18.0.2: seq=0 ttl=64 time=0.029 ms
64 bytes from 172.18.0.2: seq=1 ttl=64 time=0.062 ms
--- alpine1 ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 0.029/0.045/0.062 ms
# ping -c 2 alpine3
ping: bad address 'alpine3'
# ping -c 2 172.17.0.2
PING 172.17.0.2 (172.17.0.2): 56 data bytes
--- 172.17.0.2 ping statistics ---
2 packets transmitted, 0 packets received, 100% packet loss
$ docker container stop alpine1 alpine2 alpine3 alpine4
$ docker container rm alpine1 alpine2 alpine3 alpine4
$ docker network rm alpine-net| 1 | 由于执行了上面那句话，所以，alpine4 会出现在这里。 |
| 2 | alpine4 在 alpine-net 也出现。 — D瓜哥注：由此可以看出，利用 Docker 可以很方便地模拟网络拓扑图。然后测试各种网络问题。 |
alpine4 is connected to both the default bridge network and alpine-net. It should be able to reach all of the other containers. However, you will need to address alpine3 by its IP address.
Detach from alpine1 using detach sequence, CTRL + p CTRL + q (hold down CTRL and type p followed by q).
On user-defined networks like alpine-net, containers can not only communicate by IP address, but can also resolve a container name to an IP address. This capability is called automatic service discovery.
