多个docker节点使用直接路由的方式通信

关键技术：路由软件的使用

一、虚拟机

首先准备三台虚拟机，假设节点IP地址分别为

• docker-1: 192.168.0.30
• docker-2: 192.168.0.31
• docker-3: 192.168.0.32

在每个节点上安装docker软件，并修改Docker0网桥默认网段为

• docker-1： 10.0.1.1/16
• docker-2： 10.0.2.1/16
• docker-3： 10.0.3.1/16

比如，修改docker-1的Docker0网桥的默认网段，编辑/etc/docker/daemon.json文件，添加以下内容

{
 "bip":"10.0.1.1/24"
}

然后重启docker,查看网桥的IP地址

[root@localhost ~]# systemctl restart docker

[root@localhost ~]# ifconfig docker0
docker0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        inet 10.0.1.1  netmask 255.255.255.0  broadcast 10.0.1.255
        ether 02:42:bd:d7:e3:8b  txqueuelen 0  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

其他两个节点，也做类似的修改。

路由器

这节内容是把虚拟机节点变成一个路由器节点，下面的内容需要分别在三个节点上执行

1. 安装路由软件

yum install -y quagga

2. 启动软路由

[root@localhost ~]# cat << EOF > /etc/quagga/zebra.conf
hostname router-1
password zebra
enable password zebra
EOF
[root@localhost ~]# cat << EOF >  /etc/quagga/ripd.conf
hostname ripd
password zebra

router rip
network eth0
network docker0

neighbor 192.168.0.30
neighbor 192.168.0.31
neighbor 192.168.0.32

EOF
[root@localhost ~]# systemctl start zebra
[root@localhost ~]# systemctl start ripd

大概等待十几秒后，路由完成更新，可以查看任何一个节点的路由表

[root@localhost quagga]# ip route
default via 192.168.0.1 dev eth0
10.0.1.0/24 dev docker0 proto kernel scope link src 10.0.1.1
10.0.2.0/24 via 192.168.0.31 dev eth0 proto zebra metric 2
10.0.3.0/24 via 192.168.0.32 dev eth0 proto zebra metric 2
192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.30

可以看到，有两个路由有zibra的字样，刚好是其他两个节点的docker0的网络，我们来测试一下网络

[root@localhost ~]# ping 10.0.2.1 -c 3
PING 10.0.2.1 (10.0.2.1) 56(84) bytes of data.
64 bytes from 10.0.2.1: icmp_seq=1 ttl=64 time=0.545 ms
64 bytes from 10.0.2.1: icmp_seq=2 ttl=64 time=0.516 ms
64 bytes from 10.0.2.1: icmp_seq=3 ttl=64 time=0.839 ms

--- 10.0.2.1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 0.516/0.633/0.839/0.147 ms
[root@localhost ~]#
[root@localhost ~]#
[root@localhost ~]# ping 10.0.3.1 -c 3
PING 10.0.3.1 (10.0.3.1) 56(84) bytes of data.
64 bytes from 10.0.3.1: icmp_seq=1 ttl=64 time=0.495 ms
64 bytes from 10.0.3.1: icmp_seq=2 ttl=64 time=0.480 ms
64 bytes from 10.0.3.1: icmp_seq=3 ttl=64 time=0.455 ms

--- 10.0.3.1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 0.455/0.476/0.495/0.030 ms

我们已经打通多个节点上的容器之间的通信，下面我们可以在各个节点运行docker容器来测试网络

容器

分别在三个节点，启动一个容器，然后测试网络

[root@localhost ~]# docker run -it alpine sh
/ # ping 10.0.1.1 -c 3
PING 10.0.1.1 (10.0.1.1): 56 data bytes
64 bytes from 10.0.1.1: seq=0 ttl=64 time=0.600 ms
64 bytes from 10.0.1.1: seq=1 ttl=64 time=0.272 ms
64 bytes from 10.0.1.1: seq=2 ttl=64 time=0.268 ms

--- 10.0.1.1 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0.268/0.380/0.600 ms
/ # ping 10.0.2.1 -c 3
PING 10.0.2.1 (10.0.2.1): 56 data bytes
64 bytes from 10.0.2.1: seq=0 ttl=63 time=2.079 ms
64 bytes from 10.0.2.1: seq=1 ttl=63 time=1.292 ms
64 bytes from 10.0.2.1: seq=2 ttl=63 time=0.755 ms

--- 10.0.2.1 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0.755/1.375/2.079 ms
/ # ping 10.0.3.1 -c 3
PING 10.0.3.1 (10.0.3.1): 56 data bytes
64 bytes from 10.0.3.1: seq=0 ttl=63 time=0.886 ms
64 bytes from 10.0.3.1: seq=1 ttl=63 time=0.777 ms
64 bytes from 10.0.3.1: seq=2 ttl=63 time=0.807 ms

--- 10.0.3.1 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0.777/0.823/0.886 ms