# Exercises - ONOS (The source material of this exercise is in: https://web.archive.org/web/20221127194755/https://wiki.onosproject.org/display/ONOS/Basic+ONOS+Tutorial - Just a reference!) Use the mn-vm-wifi.ova VM as the same of Labs 1 and 2. These exercises will make you feel comfortable with ONOS. VM User: wifi VM Password: wifi This exercise is divided in three parts: 1. Deploying ONOS - ONOS commands and GUI 2. ONOS Applications 3. ONOS Intents ## Part 1: Deploying ONOS - ONOS commands and GUI Open a terminal and start ONOS as a single container instance. ```bash $ sudo docker run -t -d -p 8181:8181 -p 8101:8101 -p 5005:5005 -p 830:830 --name onos onosproject/onos:1.12.0 ``` Wait for a few seconds until ONOS starts completely. To login inside the ONOS command line use ssh (password karaf), but first get ONOS IP address. ```bash $ sudo docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' onos # The command above will return ONOS IP Address to be used in the next command $ ssh -p 8101 karaf@*ONOS IP Address* ``` Password: karaf From now on, commands will be typed in the ONOS interactive CLI. For instance, check which apps are activated. ```bash onos> apps -a -s ``` Checking the ONOS GUI, open a browser and enter http://localhost:8181/onos/ui. Login as user onos with password rocks. Probably you will not see any Topology devices in the initial screen, so let's start Mininet. In another terminal (tab or window) download the follow repository: ```bash $ wget https://github.com/intrig-unicamp/cpqd-tutorials/archive/refs/heads/master.zip $ unzip master.zip ``` Start the mininet, don't forget to fill the right **`ONOS IP Address`**. ```bash $ cd cpqd-tutorials-master/05-onos-exercises $ sudo mn --topo=att --custom=rftesttopo.py --controller remote,ip=*ONOS IP Address* --switch ovs,protocols=OpenFlow13 --mac ``` :::danger See what happened in the ONOS GUI. No devices yet, right? ::: In the mininet console try to ping hosts. ```bash mininet> h1 ping -c3 h2 ``` ## Part 2: ONOS Applications Let's start loading Apps in ONOS, so hosts can reach each other. Get back to the ONOS ssh session terminal (interactive CLI), and load some applications. ```bash onos> app activate org.onosproject.openflow onos> app activate org.onosproject.fwd ``` :::danger See what happened in the ONOS GUI. Some devices showed up, right? ::: Try to ping hosts in the mininet terminal, and let it happening for a while. ```bash mininet> h1 ping h2 ``` Go back to the ONOS CLI, activate and deactivate the apps, see how it affects ping. ``` onos> app deactivate fwd onos> app activate fwd ``` Ping all hosts in Mininet. ```bash mininet> pingall ``` Let's look at some important ONOS commands in the CLI, go typing them one by one and see what happens. ONOS has many CLI commands. ```bash onos> help ``` ONOS has a convenient command to list the device currently known in the system. Running ```bash onos> devices ``` Similarly, the links command is used to list the links detected by ONOS. At the ONOS prompt run ```bash onos> links ``` And hosts too. ```bash onos> hosts ``` :::danger If you have some spare time, check if the devices, links and hosts match the topology initiated by mininet (i.e., the custom topology file rftesttopo.py). ::: The flows command allows you to observe which flow entries are currently registered in the system. Flow entries may be in several states: * PENDING_ADD - The flow has been submitted and forwarded to the switch. * ADDED - The flow has been added to the switch. * PENDING_REMOVE - The request to remove the flow has been submitted and forwarded to the switch. * REMOVED - The rule has been removed. Keep mininet pinging: ```bash mininet> h1 ping h2 -c5 ``` Check the flows ```bash onos> flows -s ``` In the shown output, ONOS provides many details about the flows at the switches. For example each flow entry defines a selector and treatment which is the set of traffic matched by the the flow entry and how this traffic should be handled. Notice as well that each flow entry it tagged by an appId (application id), this appId identifies which application installed this flow entry. This is a useful feature because it can help an admin identify which application may be misbehaving or consuming many resources. Given a network topology, ONOS computes all the shortest paths between any two nodes. This is especially useful for your applications to obtain path information for either flow installation or some other use. The paths command takes two arguments, both of them are devices. To make things easy for you ONOS provides CLI autocompletion by simply hitting the TAB key. Try it: ```bash onos> paths <TAB> onos> paths of:0000000000000001 of:0000000000000009 ``` ## Part 3: ONOS Intents The intent command allows one to see what intents are stored in the system. Intents can be in several states: * SUBMITTED - The intent has been submitted and will be processed soon. * COMPILING - The intent is being compiled. This is a transient state. * INSTALLING - The intent is in the process of being installed. * INSTALLED - The intent has been installed. * RECOMPILING - The intent is being recompiled after a failure. * WITHDRAWING - The intent is being withdrawn. * WITHDRAWN - The intent has been removed. * FAILED - The intent is in a failed state because it cannot be satisfied. ```bash onos> intents ``` :::warning Note: You will not see any intents until some have been added. So, you will add explicit host connectivity intent. ::: The command can also tell you what type of sub-intents the intent has been compiled to: ```bash onos> intents -i ``` First, let's deactivate the Reactive Forwarding application though: ```bash onos> app deactivate fwd ``` Let's add a host connectivity intent for some two end-station hosts. You can use argument completion by pressing the Tab key. ```bash onos> onos:add-host-intent 00:00:00:00:00:01/None 00:00:00:00:00:03/None onos> intents ``` Go to the ONOS GUI, in the side panel click in the Intents options, select the listed Intent and click in the graphic signal at the corner of the screen (show in topology). :::danger What is shown in the screen? Can you check the intent path? ::: Check the ICMP pings among h1 and h3. ```bash mininet> h1 ping h3 -c5 ``` So now that the intent is installed, let's have a look what path it is using by using the flows command with summarized output using the -s flag for better readability: ```bash onos> flows -s ``` You can visualize the intent using ONOS GUI by selecting a node in the GUI and press the V key to show paths provisioned by intents that pass through the selected node. To realize if your intent is actually working in ONOS, let's play with mininet, and check if the connectivity between h1 and h3 keeps existing. ```bash mininet> link s3 s4 down ``` :::danger Check in the ONOS GUI how the path changed, and see the ONOS flows. What happened in the ONOS GUI? ::: To bring the link back ```bash mininet> link s3 s4 up ``` To tear-down mininet and onos: ```bash mininet> exit $ sudo mn -c ``` ```bash onos> logout $ sudo docker stop -t0 onos $ sudo docker rm onos ``` ## Congratulations! Now you know a little about ONOS!