网络管理
docker容器创建后，必不可少的要和其它主机或容器进行网络通信
Docker的默认的网络通信
Docker安装后默认的网络设置
Docker服务安装完成之后，默认在每个宿主机会生成一个名称为docker0的网卡其IP地址都是172.17.0.1/16
范例：安装Docker的默认的网络配置
[root@ubuntu1804 ~]#ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default 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
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 00:0c:29:34:df:91 brd ff:ff:ff:ff:ff:ff
inet 10.0.0.100/24 brd 10.0.0.255 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe34:df91/64 scope link
valid_lft forever preferred_lft forever
3: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default
link/ether 02:42:02:7f:a8:c6 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0
valid_lft forever preferred_lft forever
inet6 fe80::42:2ff:fe7f:a8c6/64 scope link
valid_lft forever preferred_lft forever
[root@ubuntu1804 ~]#brctl show
bridge name bridge id STP enabled interfaces
docker0 8000.0242027fa8c6 no范例：安装Harbor的默认网络配置
[root@ubuntu1804 ~]#ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default 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
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 00:0c:29:01:f3:0c brd ff:ff:ff:ff:ff:ff
inet 10.0.0.102/24 brd 10.0.0.255 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe01:f30c/64 scope link
valid_lft forever preferred_lft forever
3: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default
link/ether 02:42:f4:23:e8:29 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0
valid_lft forever preferred_lft forever
4: br-9af624ecd23e: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:e9:1c:1a:7b brd ff:ff:ff:ff:ff:ff
inet 172.18.0.1/16 brd 172.18.255.255 scope global br-9af624ecd23e
valid_lft forever preferred_lft forever
inet6 fe80::42:e9ff:fe1c:1a7b/64 scope link
valid_lft forever preferred_lft forever
6: veth225895c@if5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether a6:f3:0f:ae:4b:43 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet6 fe80::a4f3:fff:feae:4b43/64 scope link
valid_lft forever preferred_lft forever
8: veth244c237@if7: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether 72:12:35:11:e8:14 brd ff:ff:ff:ff:ff:ff link-netnsid 1
inet6 fe80::7012:35ff:fe11:e814/64 scope link
valid_lft forever preferred_lft forever
10: veth81ab8cb@if9: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether 5e:07:f2:eb:43:c2 brd ff:ff:ff:ff:ff:ff link-netnsid 2
inet6 fe80::5c07:f2ff:feeb:43c2/64 scope link
valid_lft forever preferred_lft forever
12: vethf8499d4@if11: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether 4e:df:12:c5:58:83 brd ff:ff:ff:ff:ff:ff link-netnsid 4
inet6 fe80::4cdf:12ff:fec5:5883/64 scope link
valid_lft forever preferred_lft forever
14: vethceabf74@if13: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether 06:c0:58:ea:51:2e brd ff:ff:ff:ff:ff:ff link-netnsid 5
inet6 fe80::4c0:58ff:feea:512e/64 scope link
valid_lft forever preferred_lft forever
16: veth47c5069@if15: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether c6:6f:aa:51:be:38 brd ff:ff:ff:ff:ff:ff link-netnsid 3
inet6 fe80::c46f:aaff:fe51:be38/64 scope link
valid_lft forever preferred_lft forever
18: veth83fde4a@if17: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether 32:74:1e:e2:81:50 brd ff:ff:ff:ff:ff:ff link-netnsid 6
inet6 fe80::3074:1eff:fee2:8150/64 scope link
valid_lft forever preferred_lft forever
20: veth2c51f87@if19: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether ca:b7:c9:da:87:92 brd ff:ff:ff:ff:ff:ff link-netnsid 7
inet6 fe80::c8b7:c9ff:feda:8792/64 scope link
valid_lft forever preferred_lft forever
22: veth0f4a931@if21: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether fa:29:a4:4d:b1:c2 brd ff:ff:ff:ff:ff:ff link-netnsid 8
inet6 fe80::f829:a4ff:fe4d:b1c2/64 scope link
valid_lft forever preferred_lft forever
24: veth55b6555@if23: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-9af624ecd23e state UP group default
link/ether aa:87:c4:2c:de:7c brd ff:ff:ff:ff:ff:ff link-netnsid 9
inet6 fe80::a887:c4ff:fe2c:de7c/64 scope link
valid_lft forever preferred_lft forever
[root@ubuntu1804 ~]#
[root@ubuntu1804 ~]#brctl show
bridge name bridge id STP enabled interfaces
br-9af624ecd23e 8000.0242e91c1a7b no veth0f4a931
veth225895c
veth244c237
veth2c51f87
veth47c5069
veth55b6555
veth81ab8cb
veth83fde4a
vethceabf74
vethf8499d4
docker0 8000.0242f423e829 no
创建容器后的网络配置
每次新建容器后
- 宿主机多了一个虚拟网卡，和容器的网卡组合成一个网卡，比如：137: veth8ca6d43@if136，而在容器内的网卡名为136，可以看出和宿主机的网卡之间的关联
- 容器会自动获取一个172.17.0.0/16网段的随机地址，默认从172.17.0.2开始，第二次容器为172.17.0.3，以此类推
创建第一个容器后的网络状态
范例：创建容器，容器自动获取IP地址
[root@ubuntu1804 ~]#docker run -it --rm alpine:3.11 sh
/ # ip a
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
136: eth0@if137: <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
valid_lft forever preferred_lft forever
/ # cat /etc/hosts
127.0.0.1 localhost
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
172.17.0.2 6b8d9f3a653e
[root@ubuntu1804 ~]#docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
6b8d9f3a653e alpine:3.11 "sh" 13 seconds ago Up 12 seconds pensive_chandrasekhar
范例：新建第一个容器，宿主机的网卡状态
[root@ubuntu1804 ~]#ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default 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
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 00:0c:29:34:df:91 brd ff:ff:ff:ff:ff:ff
inet 10.0.0.100/24 brd 10.0.0.255 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe34:df91/64 scope link
valid_lft forever preferred_lft forever
3: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:02:7f:a8:c6 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0
valid_lft forever preferred_lft forever
inet6 fe80::42:2ff:fe7f:a8c6/64 scope link
valid_lft forever preferred_lft forever
137: veth8ca6d43@if136: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default
link/ether fa:96:37:77:a9:a9 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet6 fe80::f896:37ff:fe77:a9a9/64 scope link
valid_lft forever preferred_lft forever
范例：查看新建容器后桥接状态
[root@ubuntu1804 ~]#brctl show
bridge name bridge id STP enabled interfaces
docker0 8000.0242027fa8c6 no veth8ca6d43
创建第二个容器后面的网络状态
范例：再次创建第二个容器
[root@ubuntu1804 ~]#docker run -it --rm alpine:3.11 sh
/ # ip a
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
140: eth0@if141: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue state UP
link/ether 02:42:ac:11:00:03 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.3/16 brd 172.17.255.255 scope global eth0
valid_lft forever preferred_lft forever
/ # cat /etc/hosts
127.0.0.1 localhost
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
172.17.0.3 ab3ea580804a
/ # ping ab3ea580804a
PING ab3ea580804a (172.17.0.3): 56 data bytes
64 bytes from 172.17.0.3: seq=0 ttl=64 time=0.037 ms
64 bytes from 172.17.0.3: seq=1 ttl=64 time=0.132 ms
^C
--- ab3ea580804a ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 0.037/0.084/0.132 ms
/ # ping 6b8d9f3a653e
ping: bad address '6b8d9f3a653e'
/ #
[root@ubuntu1804 ~]#docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
ab3ea580804a alpine:3.11 "sh" 9 seconds ago Up 7 seconds vigilant_jones
6b8d9f3a653e alpine:3.11 "sh" 13 seconds ago Up 12 seconds pensive_chandrasekhar
范例：新建第二个容器后又多了一个虚拟网卡
[root@ubuntu1804 ~]#ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default 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
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 00:0c:29:34:df:91 brd ff:ff:ff:ff:ff:ff
inet 10.0.0.100/24 brd 10.0.0.255 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::20c:29ff:fe34:df91/64 scope link
valid_lft forever preferred_lft forever
3: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
link/ether 02:42:02:7f:a8:c6 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0
valid_lft forever preferred_lft forever
inet6 fe80::42:2ff:fe7f:a8c6/64 scope link
valid_lft forever preferred_lft forever
137: veth8ca6d43@if136: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default
link/ether fa:96:37:77:a9:a9 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet6 fe80::f896:37ff:fe77:a9a9/64 scope link
valid_lft forever preferred_lft forever
141: vethf599a47@if140: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master docker0 state UP group default
link/ether 96:e7:52:fe:67:54 brd ff:ff:ff:ff:ff:ff link-netnsid 1
inet6 fe80::94e7:52ff:fefe:6754/64 scope link
valid_lft forever preferred_lft forever
范例：查看新建第二个容器后桥接状态
[root@ubuntu1804 ~]#brctl show
bridge name bridge id STP enabled interfaces
docker0 8000.0242027fa8c6 no veth8ca6d43
vethf599a47本文链接：http://www.yunweipai.com/34870.html
原创文章，作者：奋斗，如若转载，请注明出处：https://blog.ytso.com/52675.html