实验7：基于REST API的SDN北向应用实践

一、实验目的

1. 能够编写程序调用OpenDaylight REST API实现特定网络功能；
2. 能够编写程序调用Ryu REST API实现特定网络功能。

二、实验环境

1. 下载虚拟机软件Oracle VisualBox或VMware；
2. 在虚拟机中安装Ubuntu 20.04 Desktop amd64，并完整安装Mininet、OpenDaylight（Carbon版本）、Postman和Ryu；

三、实验要求

（一）基本要求

编写Python程序，调用OpenDaylight的北向接口实现以下功能

（1） 利用Mininet平台搭建下图所示网络拓扑，并连接OpenDaylight；

 

 

（2） 下发指令删除s1上的流表数据。

 

 

 

 

（3） 下发硬超时流表，实现拓扑内主机h1和h3网络中断20s。

 

（4） 获取s1上活动的流表数。

 

 

 

 

 

编写Python程序，调用Ryu的北向接口实现以下功能

（1） 实现上述OpenDaylight实验拓扑上相同的硬超时流表下发。

 

 

 

 

 

 

（2） 参考Ryu REST API的文档，基于VLAN实验的网络拓扑，编程实现相同的VLAN配置。

1. 提示：拓扑生成后需连接Ryu，且Ryu应能够提供REST API服务

VLAN_ID	Hosts
0	h1 h3
1	h2 h4

 

 

 

 

 

 

拓扑代码topo.py

curl -X POST -d '{
"dpid": 1,
"priority": 1,
"match":{
"in_port": 1
},
"actions":[
{
"type": "PUSH_VLAN", # Push a new VLAN tag if a input frame is non-VLAN-tagged
"ethertype": 33024 # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
},
{
"type": "SET_FIELD",
"field": "vlan_vid", # Set VLAN ID
"value": 4096 # Describe sum of vlan_id(e.g. 6) | OFPVID_PRESENT(0x1000=4096)
},
{
"type": "OUTPUT",
"port": 3
}
]
}' http://localhost:8080/stats/flowentry/add

curl -X POST -d '{
"dpid": 1,
"priority": 1,
"match":{
"in_port": 2
},
"actions":[
{
"type": "PUSH_VLAN", # Push a new VLAN tag if a input frame is non-VLAN-tagged
"ethertype": 33024 # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
},
{
"type": "SET_FIELD",
"field": "vlan_vid", # Set VLAN ID
"value": 4097 # Describe sum of vlan_id(e.g. 6) | OFPVID_PRESENT(0x1000=4096)
},
{
"type": "OUTPUT",
"port": 3
}
]
}' http://localhost:8080/stats/flowentry/add

curl -X POST -d '{
"dpid": 1,
"priority": 1,
"match":{
"vlan_vid": 0
},
"actions":[
{
"type": "POP_VLAN", # Push a new VLAN tag if a input frame is non-VLAN-tagged
"ethertype": 33024 # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
},
{
"type": "OUTPUT",
"port": 1
}
]
}' http://localhost:8080/stats/flowentry/add

curl -X POST -d '{
"dpid": 1,
"priority": 1,
"match":{
"vlan_vid": 1
},
"actions":[
{
"type": "POP_VLAN", # Push a new VLAN tag if a input frame is non-VLAN-tagged
"ethertype": 33024 # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
},
{
"type": "OUTPUT",
"port": 2
}
]
}' http://localhost:8080/stats/flowentry/add

curl -X POST -d '{
"dpid": 2,
"priority": 1,
"match":{
"in_port": 1
},
"actions":[
{
"type": "PUSH_VLAN", # Push a new VLAN tag if a input frame is non-VLAN-tagged
"ethertype": 33024 # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
},
{
"type": "SET_FIELD",
"field": "vlan_vid", # Set VLAN ID
"value": 4096 # Describe sum of vlan_id(e.g. 6) | OFPVID_PRESENT(0x1000=4096)
},
{
"type": "OUTPUT",
"port": 3
}
]
}' http://localhost:8080/stats/flowentry/add

curl -X POST -d '{
"dpid": 2,
"priority": 1,
"match":{
"in_port": 2
},
"actions":[
{
"type": "PUSH_VLAN", # Push a new VLAN tag if a input frame is non-VLAN-tagged
"ethertype": 33024 # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
},
{
"type": "SET_FIELD",
"field": "vlan_vid", # Set VLAN ID
"value": 4097 # Describe sum of vlan_id(e.g. 6) | OFPVID_PRESENT(0x1000=4096)
},
{
"type": "OUTPUT",
"port": 3
}
]
}' http://localhost:8080/stats/flowentry/add

curl -X POST -d '{
"dpid": 2,
"priority": 1,
"match":{
"vlan_vid": 0
},
"actions":[
{
"type": "POP_VLAN", # Push a new VLAN tag if a input frame is non-VLAN-tagged
"ethertype": 33024 # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
},
{
"type": "OUTPUT",
"port": 1
}
]
}' http://localhost:8080/stats/flowentry/add

curl -X POST -d '{
"dpid": 2,
"priority": 1,
"match":{
"vlan_vid": 1
},
"actions":[
{
"type": "POP_VLAN", # Push a new VLAN tag if a input frame is non-VLAN-tagged
"ethertype": 33024 # Ethertype 0x8100(=33024): IEEE 802.1Q VLAN-tagged frame
},
{
"type": "OUTPUT",
"port": 2
}
]
}' http://localhost:8080/stats/flowentry/add

 

 

（三）个人感想

本次实验让我学会能够编写程序调用OpenDaylight REST API实现特定网络功能和调用Ryu REST API实现特定网络功能。本次实验比较困难，不仅是因为对实验不了解，同时还有许多小问题，比如在下发指令删除流表时，会出现权限不够或者链接过多的问题，输入代码前要加上sudo或者清理缓存并重启电脑，如果已经删除流表后再次删除会有返回值但会报错。第二个实验之前要清除缓存，否则会出现报错。本次实验不仅学会调用OpenDaylight REST API实现特定网络功能和Ryu REST API实现特定网络功能，还了复习了关于Ryu的运行方面的操作命令，以及关于.sh脚本的命令。