docker容器是怎么进行通信的
Docker容器间通信与外网通信的操作一 容器间通信1.容器的网络共享
处于这个模式下的docker容器会共享一个网络栈，这样两个容器之间可以使用localhost高效快速通信。
使用于web服务器与应用服务器之间的通信。
##清空实验环境
[root@server1 ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
##默认网络创建容器
[root@server1 ~]# docker run -it --name vm1 ubuntu
root@b1a2a90f98a5:/# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
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
368: eth0@if369: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
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
root@b1a2a90f98a5:/# [root@server1 ~]#
##container创建与vm1 网络共享的vm2
[root@server1 ~]# docker run -it --name vm2 --network container:vm1 ubuntu
root@b1a2a90f98a5:/# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
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
368: eth0@if369: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
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
root@b1a2a90f98a5:/#
2.--link方式
##清空镜像
[root@server1 ~]# docker rm -f vm1
vm1
[root@server1 ~]# docker rm -f vm2
vm2
[root@server1 ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
##默认网络创建vm1
[root@server1 ~]# docker run -it --name vm1 ubuntu
root@68e56c57a9a0:/# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
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
370: eth0@if371: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
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
root@68e56c57a9a0:/# [root@server1 ~]#
##--link方式创建vm1子网的容器vm2
[root@server1 ~]# docker run -it --name vm2 --link vm1:web ubuntu
root@61267851b484:/# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
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
372: eth0@if373: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
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 ##ip与vm1同网段，递增
valid_lft forever preferred_lft forever
##解析文件中含有vm1 的ip 与别名等信息
root@61267851b484:/# 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 web 68e56c57a9a0 vm1
172.17.0.3 61267851b484
root@61267851b484:/# ^C
root@61267851b484:/#
--link
更新hosts文件
link容器的变量也复制过来
root@61267851b484:/# env HOSTNAME=61267851b484 TERM=xterm LS_COLORS=rs=0:di=01;34:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31;01:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;31:*.tgz=01;31:*.arj=01;31:*.taz=01;31:*.lzh=01;31:*.lzma=01;31:*.tlz=01;31:*.txz=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.dz=01;31:*.gz=01;31:*.lz=01;31:*.xz=01;31:*.bz2=01;31:*.bz=01;31:*.tbz=01;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=01;31:*.rar=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.jpg" alt="docker容器是怎么进行通信的（Docker容器间通信与外网通信的操作）" border="0" />
容器停止 ip将释放掉，开启后重新获取其他ip，link的容器自动更新hosts文件
二 容器与外网间的通信
查看当前iptable的nat表火墙策略
[root@server1 ~]# iptables -t nat -nL Chain PREROUTING (policy ACCEPT) target prot opt source destination DOCKER all -- 0.0.0.0/0 0.0.0.0/0 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 -- 0.0.0.0/0 !127.0.0.0/8 ADDRTYPE match dst-type LOCAL Chain POSTROUTING (policy ACCEPT) target prot opt source destination MASQUERADE all -- 172.26.0.0/24 0.0.0.0/0 MASQUERADE all -- 172.20.0.0/16 0.0.0.0/0 MASQUERADE all -- 172.18.0.0/16 0.0.0.0/0 MASQUERADE all -- 172.17.0.0/16 0.0.0.0/0 Chain DOCKER (2 references) target prot opt source destination RETURN all -- 0.0.0.0/0 0.0.0.0/0 RETURN all -- 0.0.0.0/0 0.0.0.0/0 RETURN all -- 0.0.0.0/0 0.0.0.0/0 RETURN all -- 0.0.0.0/0 0.0.0.0/0
##创建nginx容器，并映射端口 [root@server1 ~]# docker run -d --name nginx -p 80:80 nginx cfefe6420cfe60c46cb7a050c142af7eff86fa6d687c3577077a5b4e2c8b961c ##开启80端口 [root@server1 ~]# docker port nginx 80/tcp -> 0.0.0.0:80 [root@server1 ~]# netstat -antlp | grep 80 tcp6 0 0 :::80 :::* LISTEN 27094/docker-proxy [root@server1 ~]# iptables -t nat -nL Chain PREROUTING (policy ACCEPT) target prot opt source destination DOCKER all -- 0.0.0.0/0 0.0.0.0/0 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 -- 0.0.0.0/0 !127.0.0.0/8 ADDRTYPE match dst-type LOCAL Chain POSTROUTING (policy ACCEPT) target prot opt source destination MASQUERADE all -- 172.26.0.0/24 0.0.0.0/0 MASQUERADE all -- 172.20.0.0/16 0.0.0.0/0 MASQUERADE all -- 172.18.0.0/16 0.0.0.0/0 MASQUERADE all -- 172.17.0.0/16 0.0.0.0/0 MASQUERADE tcp -- 172.17.0.2 172.17.0.2 tcp dpt:80 Chain DOCKER (2 references) target prot opt source destination RETURN all -- 0.0.0.0/0 0.0.0.0/0 RETURN all -- 0.0.0.0/0 0.0.0.0/0 RETURN all -- 0.0.0.0/0 0.0.0.0/0 RETURN all -- 0.0.0.0/0 0.0.0.0/0 DNAT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 to:172.17.0.2:80 [root@server1 ~]#
以上为个人经验，希望能给大家一个参考，也希望大家多多支持开心学习网。如有错误或未考虑完全的地方，望不吝赐教。