Goal: Controlling Pakcet network using simple Ryu app.
Requirements: A basic knowlege of Ryu and OpenFlow is required.
Dependencies: This tutorial only uses ThreePktTopo_with_Taps.py from the repo which creates a packet network with 3 switches.
Environment: I have used the VM from sdn hub, I recommond you do the same. Link for installation is provided below: http://sdnhub.org/tutorials/sdn-tutorial-vm/
Creates a simple Ryu-OE app.
Follwo instruction in the readme file of Ryu-OE git hub to setup the controlller.
First let's just test the Ryu-OE on a optical network. To do so a optical network is created. The optical network is not connected to any packet switches. To be more precise, the oprical network is only connected to tap interfaces on the edges. Later with the use of tap interfaces, mininet can connect its packet switches to the tap interfaces which results in packet and optical network.
The readme file of Ryu-OE git hub to setup the controlller.
However, the command is essentially the below:
sudo ryu-manager ~/ryu-oe/ryu/app/ofctl_rest.pyNote that I have Ryu-OE in the following directory:
ubuntu@sdnhubvm:~/ryu-oe[10:10] (master)$ pwd /home/ubuntu/ryu-oe
There will be no packet switch in this topo (i.e. no miininet is used).
a. Clearting the tap interfaces:
For this section I have created a bash script called TapSetup.bash that takes care of tap interfaces.
sudo bash TapSetup.bash 3 up
The first argument is the number of tap interfaces and the second one is up which also brings the interfaces up.
The command creates 3 tap interfaces called tap1, tap2 and tap3.
b. Set up the sys.config file
To do so we need to have LINC installed.
The topology of optical network is stoted in rel/files/sys.config file. The below topo has 3 optical switches.
For more information on the file and ocnfiguration do this tutorial. Configuration is as the following:
[{linc,
[{of_config,disabled},
{capable_switch_ports,
[{port,1,[{interface,"tap1"}]},
{port,2,[{interface,"dummy"}, {type, optical}]},
{port,3,[{interface,"dummy"}, {type, optical}]},
{port,4,[{interface,"tap2"}]},
{port,5,[{interface,"dummy"}, {type, optical}]},
{port,6,[{interface,"dummy"}, {type, optical}]},
{port,7,[{interface,"tap3"}]}
]},
{capable_switch_queues, []},
{optical_links, [{{1,2}, {2,1}}, {{2,3},{3,1}} ]},
{logical_switches,
[{switch,1,
[{backend,linc_us4_oe},
{controllers,[{"Switch0-Controller","localhost",6633,tcp}]},
{controllers_listener,disabled},
{queues_status,disabled},
{datapath_id, "00:00:00:00:00:01:00:01"},
{ports,[{port,1,[{queues,[]}, {port_no, 1}]},
{port,2,[{queues,[]}, {port_no, 2}]}
]}]},
{switch,2,
[{backend,linc_us4_oe},
{controllers,[{"Switch0-Controller","localhost",6633,tcp}]},
{controllers_listener,disabled},
{queues_status,disabled},
{datapath_id, "00:00:00:00:00:01:00:02"},
{ports,[{port,3,[{queues,[]}, {port_no, 1}]},
{port,4,[{queues,[]}, {port_no, 2}]},
{port,5,[{queues,[]}, {port_no, 3}]}
]}]},
{switch,3,
[{backend,linc_us4_oe},
{controllers,[{"Switch0-Controller","localhost",6633,tcp}]},
{controllers_listener,disabled},
{queues_status,disabled},
{datapath_id, "00:00:00:00:00:01:00:03"},
{ports,[{port,6,[{queues,[]}, {port_no, 1}]},
{port,7,[{queues,[]}, {port_no, 2}]}
]}]}
]}]},
{of_protocol, [{no_multipart, false}]},
{enetconf,
[{capabilities,[{base,{1,1}},{startup,{1,0}},{'writable-running',{1,0}}]},
{callback_module,linc_ofconfig},
{sshd_ip,any},
{sshd_port,1830},
{sshd_user_passwords,[{"linc","linc"}]}]},
{epcap,
[{verbose, false},
{stats_interval, 10},
{buffer_size, 73400320}]},
{lager,
[{handlers,
[{lager_console_backend,debug},
{lager_file_backend,
[{"log/error.log",error,10485760,"$D0",5},
{"log/debug.log",debug,10485760,"$D0",5},
{"log/console.log",info,10485760,"$D0",5}]}]}]},
{sasl,
[{sasl_error_logger,{file,"log/sasl-error.log"}},
{errlog_type,error},
{error_logger_mf_dir,"log/sasl"},
{error_logger_mf_maxbytes,1048576000000},
{error_logger_mf_maxfiles,5}]},
{sync,
[{excluded_modules, [procket]}]}].d. start LINC-OE:
make rel && sudo rel/linc/bin/linc consoleif make rel did not work try
sudo make rel
When you run Rye-OE with ofctl_rest.py file you shoudl see something like the below:
ubuntu@sdnhubvm:~/ryu-oe[07:53] (master)$ sudo ryu-manager ~/ryu-oe/ryu/app/ofctl_rest.py
loading app /home/ubuntu/ryu-oe/ryu/app/ofctl_rest.py
loading app ryu.controller.ofp_handler
loading app ryu.controller.ofp_handler
instantiating app None of DPSet
creating context dpset
creating context wsgi
instantiating app /home/ubuntu/ryu-oe/ryu/app/ofctl_rest.py of RestStatsApi
instantiating app ryu.controller.ofp_handler of OFPHandler
(11528) wsgi starting up on http://0.0.0.0:8080/
The Ryu-OE starts a web server which lets you use REST API to access the network element's data.
As you see from the output, the rest API is accesible from http://0.0.0.0:8080/ URL.
If you go to the http://0.0.0.0:8080/stats/switches URL on your browser, you would get something like the below in the browser:
[65537, 65538, 65539]
The above is the switch DPIDs of the switches. If you look at the coonfiguration file you see that the first
switch has datapath_id of 00:00:00:00:00:01:00:01. And guess what, 0000000000010001 in HEX is equal to
65537 in decimal. Here is the config for 65537 switch:
... more
{switch,1,
[{backend,linc_us4_oe},
{controllers,[{"Switch0-Controller","localhost",6633,tcp}]},
{controllers_listener,disabled},
{queues_status,disabled},
{datapath_id, "00:00:00:00:00:01:00:01"}, -> This is equal to 65537
{ports,[{port,1,[{queues,[]}, {port_no, 1}]},
{port,2,[{queues,[]}, {port_no, 2}]}
]}]},
{switch,2,
... more