[docker 网络]docker跨主机网络 ovs gre 测试1

1. 准备工作

1.1 ovs 安装

参考该文章 https://blog.csdn.net/wodeamd1/article/details/81282437

1.2 对docker网络类型有基本了解

可以参考[mydocker]---docker的四种网络模型与原理实现(1) 和 [mydocker]---docker的四种网络模型与原理实现(2).

1.2 两台机器

vm1

[root@vm1 ~]# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.19.0.12  netmask 255.255.240.0  broadcast 172.19.15.255
        inet6 fe80::5054:ff:fe4b:71f8  prefixlen 64  scopeid 0x20<link>
        ether 52:54:00:4b:71:f8  txqueuelen 1000  (Ethernet)
        RX packets 456800  bytes 531196208 (506.5 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 133968  bytes 149845102 (142.9 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        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
[root@vm1 ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         172.19.0.1      0.0.0.0         UG    0      0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
172.19.0.0      0.0.0.0         255.255.240.0   U     0      0        0 eth0

vm2

[root@vm2 ~]# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.19.0.8  netmask 255.255.240.0  broadcast 172.19.15.255
        inet6 fe80::5054:ff:fe14:eae  prefixlen 64  scopeid 0x20<link>
        ether 52:54:00:14:0e:ae  txqueuelen 1000  (Ethernet)
        RX packets 278496  bytes 394401800 (376.1 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 36312  bytes 5027752 (4.7 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        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

[root@vm2 ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         172.19.0.1      0.0.0.0         UG    0      0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
172.19.0.0      0.0.0.0         255.255.240.0   U     0      0        0 eth0

2. 配置

gre.png

2.1 vm1中的配置

[root@vm1 ~]# ovs-vsctl show
91e815a1-1021-4c97-a21c-893ab8c28e37
    ovs_version: "2.5.1"
[root@vm1 ~]# 
[root@vm1 ~]# 
[root@vm1 ~]# ovs-vsctl add-br br0
[root@vm1 ~]# ovs-vsctl add-port br0 tep0 -- set interface tep0 type=internal
[root@vm1 ~]# ifconfig tep0 192.168.0.200 netmask 255.255.255.0
[root@vm1 ~]# ovs-vsctl add-port br0 gre10 -- set interface gre10 type=gre options:remote_ip=172.19.0.8
[root@vm1 ~]# ovs-vsctl show
91e815a1-1021-4c97-a21c-893ab8c28e37
    Bridge "br0"
        Port "gre10"
            Interface "gre10"
                type: gre
                options: {remote_ip="172.19.0.8"}
        Port "tep0"
            Interface "tep0"
                type: internal
        Port "br0"
            Interface "br0"
                type: internal
    ovs_version: "2.5.1"
[root@vm1 ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         172.19.0.1      0.0.0.0         UG    0      0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
172.19.0.0      0.0.0.0         255.255.240.0   U     0      0        0 eth0
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 tep0

2.2 vm2中的配置

[root@vm2 ~]# ovs-vsctl add-br br0
[root@vm2 ~]# ovs-vsctl add-port br0 tep0 -- set interface tep0 type=internal
[root@vm2 ~]# ifconfig tep0 192.168.0.201 netmask 255.255.255.0
[root@vm2 ~]# ovs-vsctl add-port br0 gre10 -- set interface gre10 type=gre options:remote_ip=172.19.0.12
[root@vm2 ~]# ovs-vsctl show
533800d4-246f-4099-a776-8254610db91f
    Bridge "br0"
        Port "gre10"
            Interface "gre10"
                type: gre
                options: {remote_ip="172.19.0.12"}
        Port "tep0"
            Interface "tep0"
                type: internal
        Port "br0"
            Interface "br0"
                type: internal
    ovs_version: "2.5.1"
[root@vm2 ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         172.19.0.1      0.0.0.0         UG    0      0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     1002   0        0 eth0
172.19.0.0      0.0.0.0         255.255.240.0   U     0      0        0 eth0
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 tep0

2.3 测试

-------------------------------vm1---------------------------------------
[root@vm1 ~]# ping -c 1 192.168.0.200
PING 192.168.0.200 (192.168.0.200) 56(84) bytes of data.
64 bytes from 192.168.0.200: icmp_seq=1 ttl=64 time=0.027 ms

--- 192.168.0.200 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.027/0.027/0.027/0.000 ms
[root@vm1 ~]# ping -c 1 192.168.0.201
PING 192.168.0.201 (192.168.0.201) 56(84) bytes of data.
64 bytes from 192.168.0.201: icmp_seq=1 ttl=64 time=4.20 ms

--- 192.168.0.201 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 4.204/4.204/4.204/0.000 ms
[root@vm1 ~]# 

-------------------------------vm2---------------------------------------
[root@vm2 ~]# ping -c 1 192.168.0.201
PING 192.168.0.201 (192.168.0.201) 56(84) bytes of data.
64 bytes from 192.168.0.201: icmp_seq=1 ttl=64 time=0.018 ms

--- 192.168.0.201 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.018/0.018/0.018/0.000 ms
[root@vm2 ~]# ping -c 1 192.168.0.200
PING 192.168.0.200 (192.168.0.200) 56(84) bytes of data.
64 bytes from 192.168.0.200: icmp_seq=1 ttl=64 time=0.684 ms

--- 192.168.0.200 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.684/0.684/0.684/0.000 ms

3. 模拟docker测试 (容器在同一个子网中)

图片.png

yum install bridge-utils

3.1 vm1中配置

[root@vm1 ~]# ip link add docker0 type bridge
[root@vm1 ~]# ifconfig docker0 172.17.42.1/16
[root@vm1 ~]# ip link set docker0 up
[root@vm1 ~]# ip netns list
[root@vm1 ~]# ip netns add ns1 
[root@vm1 ~]# ip link add veth0 type veth peer name veth1 
[root@vm1 ~]# brctl addif docker0 veth0
[root@vm1 ~]# ip link set veth1 netns ns1
[root@vm1 ~]# ip link set veth0 up
[root@vm1 ~]# ip netns exec ns1 sh
sh-4.2# ip link set veth1 up
sh-4.2# ip link set lo up
sh-4.2# ip addr add 172.17.1.2/16 dev veth1
sh-4.2# ifconfig
lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 2  bytes 168 (168.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 2  bytes 168 (168.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

veth1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.17.1.2  netmask 255.255.0.0  broadcast 0.0.0.0
        inet6 fe80::78b0:1eff:fe83:58c7  prefixlen 64  scopeid 0x20<link>
        ether 7a:b0:1e:83:58:c7  txqueuelen 1000  (Ethernet)
        RX packets 31  bytes 2206 (2.1 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 21  bytes 1474 (1.4 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
sh-4.2# exit
exit
[root@vm1 ~]#

3.2 vm2中配置

[root@vm2 ~]# ip link add docker0 type bridge
[root@vm2 ~]# ip addr add 172.17.43.1/16 dev docker0
[root@vm2 ~]# ip link set docker0 up
[root@vm2 ~]# ip netns list
[root@vm2 ~]# ip netns add ns1 
[root@vm2 ~]# ip link add veth0 type veth peer name veth1 
[root@vm2 ~]# brctl addif docker0 veth0
[root@vm2 ~]# ip link set veth1 netns ns1
[root@vm2 ~]# ip link set veth0 up
[root@vm2 ~]# ip netns exec ns1 sh
sh-4.2# ip link set veth1 up
sh-4.2# ip link set lo up
sh-4.2# ip addr add 172.17.2.2/16 dev veth1
sh-4.2# exit
exit
[root@vm2 ~]#

3.3 测试

从vm1的ns1中访问vm2的ns2, 相当于容器间访问

[root@vm1 ~]# ip netns exec ns1 sh
sh-4.2# ifconfig veth1
veth1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.17.1.2  netmask 255.255.0.0  broadcast 0.0.0.0
        inet6 fe80::78b0:1eff:fe83:58c7  prefixlen 64  scopeid 0x20<link>
        ether 7a:b0:1e:83:58:c7  txqueuelen 1000  (Ethernet)
        RX packets 34  bytes 2388 (2.3 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 24  bytes 1656 (1.6 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
// 访问vm2中的ns1
sh-4.2# ping -c 1 172.17.2.2
PING 172.17.2.2 (172.17.2.2) 56(84) bytes of data.
64 bytes from 172.17.2.2: icmp_seq=1 ttl=64 time=0.779 ms

--- 172.17.2.2 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.779/0.779/0.779/0.000 ms
// 访问本机docker0
sh-4.2# ping -c 1 172.17.42.1
PING 172.17.42.1 (172.17.42.1) 56(84) bytes of data.
64 bytes from 172.17.42.1: icmp_seq=1 ttl=64 time=0.063 ms

--- 172.17.42.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.063/0.063/0.063/0.000 ms
// 访问vm2中的docker0
sh-4.2# ping -c 1 172.17.43.1
PING 172.17.43.1 (172.17.43.1) 56(84) bytes of data.
64 bytes from 172.17.43.1: icmp_seq=1 ttl=64 time=1.17 ms

--- 172.17.43.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 1.170/1.170/1.170/0.000 ms
sh-4.2# exit
exit
[root@vm1 ~]#

同理vm2中的ns1也可以访问vm1中的ns1

[root@vm2 ~]# ip netns exec ns1 sh
sh-4.2# ping -c 1  172.17.2.2
PING 172.17.2.2 (172.17.2.2) 56(84) bytes of data.
64 bytes from 172.17.2.2: icmp_seq=1 ttl=64 time=0.034 ms

--- 172.17.2.2 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.034/0.034/0.034/0.000 ms
sh-4.2# ping -c 1  172.17.1.2
PING 172.17.1.2 (172.17.1.2) 56(84) bytes of data.
64 bytes from 172.17.1.2: icmp_seq=1 ttl=64 time=0.769 ms

--- 172.17.1.2 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.769/0.769/0.769/0.000 ms
sh-4.2# ping -c 1  172.17.42.1
PING 172.17.42.1 (172.17.42.1) 56(84) bytes of data.
64 bytes from 172.17.42.1: icmp_seq=1 ttl=64 time=0.724 ms

--- 172.17.42.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.724/0.724/0.724/0.000 ms
sh-4.2# ping -c 1  172.17.43.1
PING 172.17.43.1 (172.17.43.1) 56(84) bytes of data.
64 bytes from 172.17.43.1: icmp_seq=1 ttl=64 time=0.034 ms

--- 172.17.43.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.034/0.034/0.034/0.000 ms
sh-4.2# exit
exit
[root@vm2 ~]#

容器之间已经可以访问了. 接下来测试一下如下的情况. 用vm1中的ns1测试即可.

[root@vm1 ~]# ip netns exec ns1 sh
// 访问本机内网ip不通  因为ns1中没有设置默认网关
sh-4.2# ping -c 1 172.19.0.12
PING 172.19.0.12 (172.19.0.12) 56(84) bytes of data.
// 访问vm2的ip访问不了 因为没有设置iptables规则和开启ip_forward功能
sh-4.2# ping -c 1 172.19.0.8
PING 172.19.0.8 (172.19.0.8) 56(84) bytes of data.
// 访问vm2中的tep0不通 因为不属于同一个网络
sh-4.2# ping -c 1 192.168.1.200
PING 192.168.1.200 (192.168.1.200) 56(84) bytes of data.
// 访问互联网不通 因为没有设置iptables规则和开启ip_forward功能
sh-4.2# ping -c 1 www.baidu.com

vm1做如下设置

[root@vm1 ~]# echo 1 >  /proc/sys/net/ipv4/ip_forward
[root@vm1 ~]# iptables -t nat -A POSTROUTING -s 172.17.1.0/16 -o eth0 -j MASQUERADE
[root@vm1 ~]# ip netns exec ns1 sh
// 将docker0设置为ns1的默认网关
sh-4.2# route add default gw 172.17.42.1
sh-4.2# ping -c 1 172.19.0.12
PING 172.19.0.12 (172.19.0.12) 56(84) bytes of data.
64 bytes from 172.19.0.12: icmp_seq=1 ttl=64 time=0.038 ms

--- 172.19.0.12 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.038/0.038/0.038/0.000 ms
sh-4.2# ping -c 1 172.19.0.8
PING 172.19.0.8 (172.19.0.8) 56(84) bytes of data.
64 bytes from 172.19.0.8: icmp_seq=1 ttl=63 time=0.327 ms

--- 172.19.0.8 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.327/0.327/0.327/0.000 ms
sh-4.2# ping -c 1 www.baidu.com
PING www.wshifen.com (119.63.197.151) 56(84) bytes of data.
64 bytes from 119.63.197.151 (119.63.197.151): icmp_seq=1 ttl=49 time=51.4 ms

--- www.wshifen.com ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 51.474/51.474/51.474/0.000 ms
// 因为在gre中不属于同一个网络 无法访问到vm2中的tep0
sh-4.2# ping -c 1 192.168.1.200
PING 192.168.1.200 (192.168.1.200) 56(84) bytes of data.

--- 192.168.1.200 ping statistics ---
1 packets transmitted, 0 received, 100% packet loss, time 0ms
sh-4.2# exit
exit
[root@vm1 ~]#

4. 清理

vm1

[root@vm1 ~]# ovs-vsctl show
91e815a1-1021-4c97-a21c-893ab8c28e37
    Bridge "br0"
        Port "gre10"
            Interface "gre10"
                type: gre
                options: {remote_ip="172.19.0.8"}
        Port "tep0"
            Interface "tep0"
                type: internal
        Port "br0"
            Interface "br0"
                type: internal
    ovs_version: "2.5.1"
[root@vm1 ~]# ovs-vsctl del-br br0
[root@vm1 ~]# ip link delete docker0 type bridge
[root@vm1 ~]# ip link delete veth0 type veth
[root@vm1 ~]# ip netns delete ns1
[root@vm1 ~]# iptables -t nat -F
[root@vm1 ~]# ovs-vsctl show
91e815a1-1021-4c97-a21c-893ab8c28e37
    ovs_version: "2.5.1"
[root@vm1 ~]#

vm2

[root@vm2 ~]# ovs-vsctl show
533800d4-246f-4099-a776-8254610db91f
    Bridge "br0"
        Port "gre10"
            Interface "gre10"
                type: gre
                options: {remote_ip="172.19.0.12"}
        Port "tep0"
            Interface "tep0"
                type: internal
        Port "br0"
            Interface "br0"
                type: internal
    ovs_version: "2.5.1"
[root@vm2 ~]# ovs-vsctl del-br br0
[root@vm2 ~]# ip link delete docker0 type bridge
[root@vm2 ~]# ip link delete veth0 type veth
[root@vm2 ~]# ip netns delete ns1
[root@vm2 ~]# iptables -t nat -F

5. 参考

1. https://blog.csdn.net/wodeamd1/article/details/81282437
2. https://blog.csdn.net/song7999/article/details/80403527
3. Docker 容器与容器云
4. https://blog.csdn.net/qq_27366789/article/details/83348366

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[docker 网络]docker跨主机网络 ovs gre 测试1

1. 准备工作

1.1 ovs 安装

1.2 对docker网络类型有基本了解

1.2 两台机器

2. 配置

2.1 vm1中的配置

2.2 vm2中的配置

2.3 测试

3. 模拟docker测试 (容器在同一个子网中)

3.1 vm1中配置

3.2 vm2中配置

3.3 测试

4. 清理

5. 参考

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