Docker续6：容器网络

1.bridge-utils

一个用于Linux系统的网络桥接工具集。它提供了一些命令行工具，帮助用户创建、管理和配置网络桥接。网络桥接是一种将多个网络接口连接在一起，以使它们能够作为单个网络段进行通信的技术。

bridge-utils 常用的命令包括：

brctl: 用于创建和管理网络桥接。

brctl show: 显示当前系统中的桥接和相关接口的信息。

root@localhost \~\]# docker run -d -p80:80 centos:nginx //没有命名，使用id来管理容器 03554f581adcfaea5c82e28d8ed1c45bc8b1b2f9f1d5a82fc3fb1c49470dad8c \[root@localhost \~\]# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 03554f581adc centos:nginx "/bin/sh -c /usr/sbi..." 25 seconds ago Up 25 seconds 0.0.0.0:80-\>80/tcp, :::80-\>80/tcp heuristic_hawking \[root@localhost \~\]# docker inspect 03554\|grep IPAdd //查看IP "SecondaryIPAddresses": null, "IPAddress": "172.17.0.3", "IPAddress": "172.17.0.3", \[root@localhost \~\]# systemctl stop docker Warning: Stopping docker.service, but it can still be activated by: docker.socket \[root@localhost \~\]# yum -y install bridge-utils //下载bridge-utils ## 2.bridge： 所有容器连接到桥就可以使⽤外⽹，使⽤nat让容器可以访问外⽹ 使⽤ ip a s指令查看桥，所有容器连接到此桥，ip地址都是172.17.0.0/16⽹段，桥是启动docker服务后出现 \[root@localhost \~\]# brctl show //显示当前系统中的桥接和相关接口的信息 bridge name bridge id STP enabled interfaces docker0 8000.0242189f6a83 no \[root@localhost \~\]# systemctl start docker //启动docker \[root@localhost \~\]# docker start heuristic_hawking //启动容器 \[root@localhost \~\]# brctl show //显示当前系统中的桥接和相关接口的信息 bridge name bridge id STP enabled interfaces docker0 8000.0242189f6a83 no veth3054cc4 \[root@localhost \~\]# docker network ls //查看桥 NETWORK ID NAME DRIVER SCOPE 96680ca9ecd6 bridge bridge local 8380e18cdd2a host host local d8a046f15d90 none null local 多创建几个镜像，发现他们默认都是桥接模式的 \[root@localhost \~\]# docker run -d centos:nginx \[root@localhost \~\]# docker inspect 9c9c\|grep IPAdd "SecondaryIPAddresses": null, "IPAddress": "172.17.0.3", "IPAddress": "172.17.0.3", \[root@localhost \~\]# docker run -d centos:nginx \[root@localhost \~\]# docker inspect 1806\|grep IPAdd "SecondaryIPAddresses": null, "IPAddress": "172.17.0.4", "IPAddress": "172.17.0.4", \[root@localhost \~\]# brctl show bridge name bridge id STP enabled interfaces docker0 8000.0242189f6a83 no veth1061d46 veth3054cc4 veth3c9ea62 每⼀台dcoker主机上的docker0所在⽹段完全⼀样，但是会造成跨主机的容器⽆法通信 ## 3.host： 与主机共享⽹络，可让容器连接外⽹ 所有容器与docker主机在同⼀个⽹络中，容器和外⽹相互访问 优点：可以直接访问容器 缺点：端⼝占⽤，多容器同时运⾏⼀个服务，不建议，在测试环境使⽤ \[root@localhost \~\]# docker run -it --network host centos:nginx /bin/bash //绑定host主机网络，容器和宿主机共用一个IP \[root@localhost /\]# //注意：这里是在容器的家目录里，而不是宿主机的家目录里 \[root@localhost /\]# ls bin etc lib lost+found mnt proc run srv tmp var dev home lib64 media opt root sbin sys usr 发现在容器内部访问ip是宿主机的IP 在外部查看不到IP ## 4.none： 容器仅仅有lo⽹卡，不能与外界链接，在⾼级应⽤中使⽤，lo⽹卡，⽆法链接外⽹ ## 5.联盟⽹络 容器⽹络 跨主机容器之间通讯 ### （1）flannel介绍 ###  （2）原理 ###  （3）搭建 #### 1）环境准备： 新建两台主机： node1主控 192.168.1.78 node2被控 192.168.1.79 #### 2）node1主控主机 \[root@localhost \~\]# yum -y install etcd flannel //安装etcd数据库，flannel \[root@localhost \~\]# vim /etc/etcd/etcd.conf //修改etcd配置文件   \[root@localhost \~\]# systemctl start etcd.service //启动服务 \[root@localhost \~\]# systemctl enable etcd.service //开机自启 \[root@localhost \~\]# netstat -lntup\|grep 2379 //查看两个端口是否打开 tcp6 0 0 :::2379 :::\* LISTEN 1661/etcd \[root@localhost \~\]# netstat -lntup\|grep 4001 tcp6 0 0 :::4001 :::\* LISTEN 1661/etcd \[root@localhost \~\]# etcdctl set a 100 //测试数据库功能 100 \[root@localhost \~\]# etcdctl get a //访问数据 100 \[root@localhost \~\]# etcdctl -C http://192.168.1.78:4001 cluster-health //查看集群是否健康 member 8e9e05c52164694d is healthy: got healthy result from http://192.168.1.78:2379 cluster is healthy \[root@localhost \~\]# etcdctl -C http://192.168.1.78:2379 cluster-health member 8e9e05c52164694d is healthy: got healthy result from http://192.168.1.78:2379 cluster is healthy \[root@localhost \~\]# vim /etc/sysconfig/flanneld //修改flannel的配置文件  \[root@localhost \~\]# etcdctl mk /atomic.io/network/config '{ "Network" : "172.20.0.0/16" }' //指定容器IP地址的分配 { "Network" : "172.20.0.0/16" } \[root@localhost \~\]# etcdctl get /atomic.io/network/config //查看是否存入成功 { "Network" : "172.20.0.0/16" } \[root@localhost \~\]# systemctl start flanneld.service //启动 \[root@localhost \~\]# systemctl enable flanneld.service //开机自启 \[root@localhost \~\]# ip a s //这里看到分配：172.20.59.0 3: flannel0: \ mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500 link/none inet 172.20.59.0/16 scope global flannel0 安装docker 运行脚本source docker.sh \[root@localhost \~\]# systemctl start docker.service //启动docker \[root@localhost \~\]# ip a s 1: lo: \ 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 2: ens33: \ mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 1000 link/ether 00:0c:29:6e:0c:3f brd ff:ff:ff:ff:ff:ff inet 192.168.1.78/24 brd 192.168.1.255 scope global noprefixroute ens33 3: flannel0: \ mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500 link/none inet 172.20.59.0/16 scope global flannel0 4: docker0: \ mtu 1500 qdisc noqueue state DOWN group default link/ether 02:42:1e:73:65:22 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 \[root@localhost \~\]# cat /run/flannel/subnet.env //查看flannel子网ip FLANNEL_NETWORK=172.20.0.0/16 FLANNEL_SUBNET=172.20.59.1/24 //待会要用 FLANNEL_MTU=1472 //待会要用 FLANNEL_IPMASQ=false \[root@localhost \~\]# vim /etc/docker/daemon.json //编辑docker.json文件 { "registry-mirrors": \[ "https://do.nark.eu.org", "https://dc.j8.work", "https://docker.m.daocloud.io", "https://dockerproxy.com", "https://docker.mirrors.ustc.edu.cn", "https://docker.nju.edu.cn" \], "hosts": \[ "tcp://0.0.0.0:2375", "unix:///var/run/docker.sock" \], "bip" : "172.20.59.1/24", "mtu" : 1472 } \[root@localhost \~\]# vim /usr/lib/systemd/system/docker.service //修改docker配置文件  \[root@localhost \~\]# systemctl daemon-reload //加载配置 \[root@localhost \~\]# systemctl restart docker //重启服务 \[root@localhost \~\]# ip a s //这里看到docker网卡已经与flannel属于同一网段了 1: lo: \ 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 2: ens33: \ mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 1000 link/ether 00:0c:29:6e:0c:3f brd ff:ff:ff:ff:ff:ff inet 192.168.1.78/24 brd 192.168.1.255 scope global noprefixroute ens33 3: flannel0: \ mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500 link/none inet 172.20.59.0/16 scope global flannel0 4: docker0: \ mtu 1472 qdisc noqueue state DOWN group default link/ether 02:42:1e:73:65:22 brd ff:ff:ff:ff:ff:ff inet 172.20.59.1/24 brd 172.20.59.255 scope global docker0 测试IP地址： \[root@localhost \~\]# docker pull centos //下载镜像 \[root@localhost \~\]# docker run -it centos:latest /bin/bash //创建容器 \[root@80ff4428d236 /\]# ctrl+p+q退出 \[root@localhost \~\]# docker inspect 80f\|grep IPAdd //这里看到容器的IP地址已经是flannel分配的了 "SecondaryIPAddresses": null, "IPAddress": "172.20.59.2", "IPAddress": "172.20.59.2", #### 3）node2被控主机 \[root@localhost \~\]# yum -y install flannel \[root@localhost \~\]# vim /etc/sysconfig/flanneld  \[root@localhost \~\]# systemctl start flanneld.service \[root@localhost \~\]# ip a s //可以看到flannel为我们分配了IP地址 1: lo: \ 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 2: ens33: \ mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 1000 link/ether 00:0c:29:56:9e:63 brd ff:ff:ff:ff:ff:ff inet 192.168.1.79/24 brd 192.168.1.255 scope global noprefixroute ens33 3: flannel0: \ mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500 link/none inet 172.20.93.0/16 scope global flannel0 \[root@localhost \~\]# cat /run/flannel/subnet.env FLANNEL_NETWORK=172.20.0.0/16 FLANNEL_SUBNET=172.20.93.1/24 FLANNEL_MTU=1472 FLANNEL_IPMASQ=false \[root@localhost \~\]# source docker.sh //安装docker \[root@localhost \~\]# vim /etc/docker/daemon.json //编辑daemon.json文件 { "registry-mirrors": \[ "https://do.nark.eu.org", "https://dc.j8.work", "https://docker.m.daocloud.io", "https://dockerproxy.com", "https://docker.mirrors.ustc.edu.cn", "https://docker.nju.edu.cn" \], "hosts": \[ "tcp://0.0.0.0:2375", "unix:///var/run/docker.sock" \], "bip" : "172.20.93.1/24", "mtu" : 1472 } \[root@localhost \~\]# vim /usr/lib/systemd/system/docker.service //修改docker配置文件  \[root@localhost \~\]# systemctl daemon-reload //加载配置 \[root@localhost \~\]# systemctl restart docker //重启服务 \[root@localhost \~\]# ip a s //这里看到docker网卡已经与flannel属于同一网段了 1: lo: \ 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 2: ens33: \ mtu 1500 qdisc pfifo_fast state UNKNOWN group default qlen 1000 link/ether 00:0c:29:56:9e:63 brd ff:ff:ff:ff:ff:ff inet 192.168.1.79/24 brd 192.168.1.255 scope global noprefixroute ens33 3: flannel0: \ mtu 1472 qdisc pfifo_fast state UNKNOWN group default qlen 500 link/none inet 172.20.93.0/16 scope global flannel0 4: docker0: \ mtu 1472 qdisc noqueue state DOWN group default link/ether 02:42:d4:f3:5c:66 brd ff:ff:ff:ff:ff:ff inet 172.20.93.1/24 brd 172.20.93.255 scope global docker0 测试IP地址： 1.下载一个镜像 2.创建容器 3.查看该容器IP