Mininet Custom Topologies 

My professor has given out python assignments that use the mininet VM, but he has not taught a single thing about python or mininet. When I asked an assistant during office hours, they told me to use google or youtube. So here I am and thank you

I created the same mesh few days ago but not with a tricky loop as you did. When I tested it using pox L3.learning controller, I got stuck in loops which proved to me that this L3.Learning is not even near any router as they were claiming on documentation that its simple router. It was great to learn that floodlight can handle loops !

Thank you David !👍

Thanks for the all the videos !!

Can you explain how did youcreat the py files. Because my real problem is about creating topologies not running them. Do you have a video about how to create custom topologies from scratch?

Very helpful. Thank you very much 🙏🙏🙏🙏🙏🙏

Nicely crafted videos! Thanks for posting thoses

Hey David, love the videos and found them incredibly useful

Hello David , could you Tell me how to connect a specific switch to a controller .. and let other OVSS talk to Controller through The 1st OVSS Thanks.

There is big problem with ring or mesh SDN typologies which creates a loop. I have tested ODL all versions and POX but none of them worked well with these kind of topos, so it is only possible to use spanning tree protocol in our topology to prevent loops. in this tutorial you are believing that floodlight controller can prevent such kind of loops by defult automatically? e.g: is it possible to create this topo with floodlight correctly? sudo mn --topo torus,3,3 ?

This's really great! thanks!

Thanks David. I have a question, your help would be greatly appreciated. How do I add a Router in mininet?

Awesome video!

@swapnil- you're welcome!

Good explanation. But the mesh topology doesn't work with POX controller running in the background. As soon as I run the sudo mn command, pox controller closes. Any reason?

Thanks David. I have a question, your help would be greatly appreciated. How do I add a Router in mininet? or how I can ensure the reachability if we create 2 edge in 2 different network

Is it possible to add a switch that is not OpenFlow enabled? I'm new to mininet and networking itself, and I'm doing research for my bachelor's degree to compare the performance of a tradition network with an SDN. If not, please advice me on the best way to do this

I'm trying to find the home/mininet directory on my laptop but I don't know where it is. How do I find it?

thanks David for this video, how can we limit link bandwidth and add delay between s1-eth1 to s2-eth1 & s1-eth3 to s3-eth1, , and if we set lower bandwidth and delay(in topology you have shown in this video ) will packet changes its path dynamically to reach destination

What should be done if there is no connectivity ? I tried the basic 2host 2 switch but the ping doesn't seem to work. Any idea where could be the problem or maybe where am i supposed to edit ?

Hi, can you help me if we can generate the image of the network that is built using MININET.

can you help me ? , i'll create custom topologi link aggregation (with lacp) between switch1 and switch2 with ryu controller. i'm newbie in mininet, what should i do?

Hi david I tried to modify a emptynet.py file and I didn't find the file in my computer. I mean I f I want modify any file in examples folder or custom how can find it in my computer

i m trying to change topology in onos basic tutorial but i m not able to do it can you please help me ?

Hello David, Thanks for the video, it's really helpful and it would be great if you can create a video using RYU controller.

sir ,can you please tell me how to receive a text file/audio/video in form of output if a request is made from one host to another host in mininet

Dear David Mahler, I wrote a topology but I face an error saying an exception caught. I was wondering if you'd mind sending a link for me about a custom topology, I'm new to mininet. Bests,

Hi everybody, I'm traying to change mininet link properties but i can't. Anyone know some way to do it? For example after add "net.addLink(h1, s4, 0, 3, bw=100, delay='5ms', loss=0, max_queue_size=1000, use_htb=True )" in python script. There are any command to change the delay or the bandwidth with mininet running? mininet>---- Thanks

Hi David, thanks for all the awesome videos, I learnt a lot from them. Just one query, I was trying to create my own custom topology, how do I run the Floodlight Controller in the background ?(time: 3:52)

Hi thanks for your awesome videos ! Can you please explain how you handled the loops between the switches with floodlight and how you prevented the crash you mentioned.

Thanks David. I have a doubt, in the begining of the tutorial you mentioned that you experienced loops because of the mesh topology. But when you use Floodlight Controller you said it was removed, using the forwarding module in the controller. My doubt is if the switch doesn't have the flow for a particular destination, it will forward the packet to the Controller and Controller will broadcast ( as like traditional Switch learning). And this broadcast will turn into loop. In that case the only way to avoid loops is to install the flows automatically in the switches. Will the Floodlight controller knows all the switches,hosts and port details, if so how? And am sorry if I have understood wrongly. Please clear my doubts.

DAvid, thanks for the video.. I have a problem setting the BW, Delay, loss. I mean , I want to change the network's performance parameter but I always get this error : line 32, in emptyNet net.addLink( leftHost, leftSwitch, **linkopts) #, bw=10, delay='5ms', loss=10, max_queue_size=1000, use_htb=True ) File "/usr/local/lib/python2.7/dist-packages/mininet-2.0.0-py2.7.egg/mininet/net.py", line 245, in addLink return cls( node1, node2, **defaults ) TypeError: __init__() got an unexpected keyword argument 'delay' I've added the library : from mininet.link import TCLink.. however I still have the error.

Hi David, I have a script used in hedera/dctopo.py that I would like to run in Mininet. I just do not know where to put the file and what command should I type!

How i create any custom topology ? commands ?

hey good information there.. i have a question, how do we create a fan-in type topology with n no. of hosts.. i believe we need to use the loop here.. can you please give me an example. thanks.

hi, can you help me? i wanna know if it is posibble to put a router and a switch in the same topo, thnks for share this video

Hey david, I tried implementing a Peterson graph topology using a python script with 5 hosts and 10 switches, but the hosts are not able to ping each other. PS: I tried including all of the available controllers, but none of them yielded the desired result. Any idea how to fix this? Thank you!

Hi Dave I'm using controllers2.py file to create a 2 controller network and c1-s1 and c2-s2 when I do a ping why c1update s2 not c1 how can I change c2 to update s2 please (c=controller s=switch)

super, thanks

I tried the command line, it says it can't find the file I want to use.

Can I calculate trust & energy for each node, while implementing IOT purpose? Also is there any process to setup a database for each node to store information?

Hi David, thank you very much. I'm really passionate about learning mininet. I have a small query, any help would be greatly appreciated. I want to setup a Ipv6 network with 2 hosts and 2 routers. Is it possible to create a ipv6 network within mininet even if my internet service provider doesn't provide the Ipv6 internet service.

Hi David Thanks for the video. Can you please tell me, how to run traceroute between hosts here. I want to see the path of the packet flow between h1 and h2. I tried "traceroute h2" from h1 xterm with no success.

Hi David, I tried to create the same topology using MiniEdit and when I tried to ping h2 from h1, I wasn't getting any response. Can you please help me here? I am not able to understand why the two hosts aren't talking to each other.

hello , do you have mybe some videos about Maxinet and how can two networks see each other on Maxinet ?

Thank you so much for all video you share with us. it's very helpfull. I tried to create the same topology but using a default controller of mininet. but when Pingall I got the error bellow. ** Ping: testing ping reachability h1 -> X h2 -> X *** Results: 100% dropped (2/2 lost) do you think that this topology is not working with default controller?

here is one more for your reference : aditya@ubuntu:~/mininet/custom$ sudo mn --custom r1.py --topo mytopo --controller=remote,ip=10.0.0.11 -------------------------------------------------------------------------------- Caught exception. Cleaning up... TypeError: custom() got multiple values for keyword argument 'self' -------------------------------------------------------------------------------- aditya@ubuntu:~/mininet/custom$

How can i reach to ~/mininet/custom$ file ?

Hi David. Could you please tell me how can we have multiple links between mininet host and a switch. I tried to create a custom topology like this but it did not work. pastebin.com/m1y5NnZT In the above topology I used "self.addLink(H1,S1)" twice. The net command gives me the following result which is totally weird. mininet> net h1 h1-eth1:s1-eth2 h2 h2-eth0:s2-eth1 s1 lo: s1-eth2:s2-eth2 s2 lo: s2-eth1:h2-eth0 s2-eth2:s1-eth2 c0

hey , as per your video and other contents online I added my topology file - router.py at this location - home-mininet-custom then I did this : aditya@ubuntu:~/mininet/custom$ dir README topo-2sw-2host.py aditya@ubuntu:~/mininet/custom$ sudo mn --custom route.py --topo mytopo -------------------------------------------------------------------------------- Caught exception. Cleaning up... TypeError: custom() got multiple values for keyword argument 'self' -------------------------------------------------------------------------------- aditya@ubuntu:~/mininet/custom$ how can I remove this error???

just to complete my question this is the result I obtained after created the network and run the dump command. mininet@mininet-vm:~/mininet/custom$ sudo mn --custom test.py --topo mytopo *** Creating network *** Adding controller *** Adding hosts: h1 h2 *** Adding switches: s1 s2 s3 s4 *** Adding links: (h1, s1) (h2, s3) (s1, s2) (s1, s3) (s1, s4) (s2, s3) (s2, s4) (s3, s4) *** Configuring hosts h1 h2 *** Starting controller *** Starting 4 switches s1 s2 s3 s4 *** Starting CLI: mininet> dump mininet> pingall *** Ping: testing ping reachability h1 -> X h2 -> X *** Results: 100% dropped (2/2 lost) mininet>

Hi Thanks for your screenshot and nice teaching. I did all of the steps the same as you did. but I donot know why I cannot run my custom topology. Unfortunatly I encountered to this error!!! mininet@mininet-vm:~/mininet/custom$ sudo mn --custom mesh.py --topo mytopo Traceback (most recent call last): File "/usr/local/bin/mn", line 5, in pkg_resources.run_script('mininet==2.0.0', 'mn') File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 499, in run_scr ipt self.require(requires)[0].run_script(script_name, ns) File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 1239, in run_sc ript execfile(script_filename, namespace, namespace) File "/usr/local/lib/python2.7/dist-packages/mininet-2.0.0-py2.7.egg/EGG-INFO/ scripts/mn", line 280, in MininetRunner() File "/usr/local/lib/python2.7/dist-packages/mininet-2.0.0-py2.7.egg/EGG-INFO/ scripts/mn", line 111, in __init__ self.parseArgs() File "/usr/local/lib/python2.7/dist-packages/mininet-2.0.0-py2.7.egg/EGG-INFO/ scripts/mn", line 145, in parseArgs self.parseCustomFile( filename ) File "/usr/local/lib/python2.7/dist-packages/mininet-2.0.0-py2.7.egg/EGG-INFO/ scripts/mn", line 132, in parseCustomFile execfile( fileName, customs, customs ) File "mesh.py", line 24 S1 = self.addSwitch( 's1' ) ^ IndentationError: unindent does not match any outer indentation level would you mind help me about that??!!! thanks so much

By following this... www.projectfloodlight.org/getting-started/ @cool inno

thank you , can you give me your email to connect you ?

hey david how can i run a mininet CLI command from a python code

How did you ~copy and update the python script in gnu nano

hey david how can i run a mininet CLI command from a python code