| | 1 | |
| | 2 | [[PageOutline]] |
| | 3 | = 1. Create an experiment = |
| | 4 | Now that your project is all setup, you are ready to run your first GENI experiment. For the purpose of this tutorial we are going to use a sample assignment that compares a UDP based transfer protocol with a TCP one. |
| | 5 | |
| | 6 | {{{ |
| | 7 | #!html |
| | 8 | <table border="0"> |
| | 9 | |
| | 10 | <tr> |
| | 11 | <td> |
| | 12 | |
| | 13 | <img border="0" src="http://groups.geni.net/geni/attachment/wiki/GENIExperimenter/Graphics/add-resources-portal.png?format=raw" alt="Create a GENI Project" height="120" title="Create a GENI Project" /> </a> |
| | 14 | </td> |
| | 15 | <td > |
| | 16 | <ol> |
| | 17 | <li> Go to the <i>Home</i> tab. </li> |
| | 18 | <li> In the project that <b>you</b> created press the <b>Create Slice</b> button</li> |
| | 19 | <li> <FONT COLOR="black">As a slice name use <code>udt</code>, you can leave the description empty and press <b>Create Slice</b></font> |
| | 20 | </li> |
| | 21 | <li> Select <b>Add Resources</b></li> |
| | 22 | <li>Since this if the first time you are trying to reserve resources, you should see a warning on the top about not having an SSH key in your account. Access to compute resources in GENI is provide through ssh key pairs and thus the portal needs a public key to upload to compute resources. For the purposes of the tutorial we will have the portal creating an SSH key pair for you. However, if you prefer to use your personal public key you can choose to upload it. Click on the <b>Generate and Download SSH Keypair</b> button.</li> |
| | 23 | |
| | 24 | <li>Press the <b>Download Private Key</b> button</li> |
| | 25 | <li> Open a terminal and execute <code>ssh-add ~/Downloads/id_geni_ssh_rsa</code> </li> |
| | 26 | <li> <FONT COLOR="black">Go to the <i>Slices</i> tab and press again on the <b>Add Resources</b> button. This time there should be no warning. Complete the form as as shown in the picture on the left and press the <b>Reserve Resources</b> button </font></li> |
| | 27 | <li> While we wait for our resources to get ready, lets look at another tool that is integrated with the portal. <FONT COLOR="black">Go to the <i>Slices</i> tab and press the <b>Launch Flack</b> button.</li> |
| | 28 | |
| | 29 | </ol> |
| | 30 | </td> |
| | 31 | |
| | 32 | </tr> |
| | 33 | </table> |
| | 34 | }}} |
| | 35 | |
| | 36 | = 2. Run your experiment = |
| | 37 | Once your resources are ready, your slice in Flack will be green. We can now continue to the interesting part of running through the sample assignment. In this sample assignment the students will experiment with a UDP-based (UDT) and a TCP-based(FTP) file transfer protocols. For the purpose of this tutorial we have made the assignment much simpler, but you can see the complete assignment [wiki:UDTExampleExperiment here]. |
| | 38 | |
| | 39 | In order to be able to complete this assignment we need to: |
| | 40 | * [#a2a.LogintoNodes login to our nodes] |
| | 41 | * learn how to have a [#a2b.UDTvsFTPExperiment complete run comparing UDT and FTP] |
| | 42 | * learn to to [#a2c.ModifyLinkParameters view and modify] the parameters of the link between the server and the client hosts |
| | 43 | === 2a. Login to Nodes === |
| | 44 | {{{ |
| | 45 | #!html |
| | 46 | <table border="0"> |
| | 47 | |
| | 48 | <tr> |
| | 49 | <td align="center"> |
| | 50 | |
| | 51 | <img border="0" src="http://groups.geni.net/geni/attachment/wiki/GENIExperimenter/Graphics/flack-host.png?format=raw" alt="Flack Host" width="100" title="Create a GENI Project" /> |
| | 52 | <br/><br/> |
| | 53 | <img border="0" src="http://groups.geni.net/geni/attachment/wiki/GENIExperimenter/Graphics/flack-ssh.png?format=raw" alt="Flack host ssh" width="250" title="Create a GENI Project" /> |
| | 54 | </td> |
| | 55 | <td > |
| | 56 | <ol> |
| | 57 | <li> While your slice is loaded in Flack, <b> press the blue (i) button</b> on a host. This will load the information about the host. </li> |
| | 58 | <li> On the top of the new tab that showed up, <b> press the ssh button </b>. This will cause the ssh client to launch. If you have setup the the key correctly, you should get logged in to your host. </li> |
| | 59 | <li> Repeat this process for all hosts; <b><code> server, clienth, delay </code></b> |
| | 60 | </li> |
| | 61 | |
| | 62 | </ol> |
| | 63 | </td> |
| | 64 | |
| | 65 | </tr> |
| | 66 | </table> |
| | 67 | }}} |
| | 68 | |
| | 69 | You should now have three terminals open, one for each host. |
| | 70 | |
| | 71 | === 2b. UDT vs FTP Experiment === |
| | 72 | |
| | 73 | For the purpose of this tutorial, we have automated a single run of the experiment that compare UDT and FTP over a single file transfer between the client and the server. In the server we have placed 4 files of different sizes: sm.1M, med.10M, lg.100M, xl.1000M. In the terminal window of the `clienth` host run: |
| | 74 | {{{ |
| | 75 | [inki@clienth ~]$ /local/scripts/get_both_file.sh sm.1M |
| | 76 | FTP: 1M in 255 ms |
| | 77 | UDT: 1M in 552 ms |
| | 78 | }}} |
| | 79 | |
| | 80 | Try the same for the other files, you can skip the xl.1000M, since it will take a bit to complete. |
| | 81 | |
| | 82 | |
| | 83 | === 2c. Modify Link Parameters === |
| | 84 | |
| | 85 | In this experiment, you'll be changing the characteristics of the link and measuring how they affect UDT and TCP performance. |
| | 86 | |
| | 87 | * In the terminal of the delay node run this command: |
| | 88 | {{{ |
| | 89 | %sudo ipfw pipe show |
| | 90 | }}} |
| | 91 | |
| | 92 | You'll get something like this: |
| | 93 | {{{ |
| | 94 | 60111: 100.000 Mbit/s 1 ms 50 sl. 1 queues (1 buckets) droptail |
| | 95 | mask: 0x00 0x00000000/0x0000 -> 0x00000000/0x0000 |
| | 96 | BKT Prot ___Source IP/port____ ____Dest. IP/port____ Tot_pkt/bytes Pkt/Byte Drp |
| | 97 | 0 ip 207.167.175.72/0 195.123.216.8/6 7 1060 0 0 0 |
| | 98 | 60121: 100.000 Mbit/s 1 ms 50 sl. 1 queues (1 buckets) droptail |
| | 99 | mask: 0x00 0x00000000/0x0000 -> 0x00000000/0x0000 |
| | 100 | BKT Prot ___Source IP/port____ ____Dest. IP/port____ Tot_pkt/bytes Pkt/Byte Drp |
| | 101 | 0 ip 207.167.176.224/0 195.124.8.8/6 8 1138 0 0 0 |
| | 102 | }}} |
| | 103 | |
| | 104 | This information shows the internal configuration of the "pipes" used to emulate network characteristics. |
| | 105 | (Your output may look different, depending on the version of ipfw installed on your delay node. |
| | 106 | In any case, the information you need is on the first line of output for each pipe.) |
| | 107 | |
| | 108 | You'll want to make note of the two pipe numbers, one for each direction of traffic along your link. |
| | 109 | In the example above, they are 60111 and 60121. |
| | 110 | |
| | 111 | There are three link characteristics we'll manipulate in this experiment: bandwidth, delay, and packet loss rate. |
| | 112 | You'll find their values listed in the ipfw output above. |
| | 113 | The link bandwidth appears on the first line immediately after the pipe number. It's 100Mbps in the example shown above. |
| | 114 | The next value shown is the delay, 1 ms in the example above. |
| | 115 | The packet loss rate (PLR) is omitted if it's zero, as shown above. If non-zero, you'll see something like '''plr 0.000100''' |
| | 116 | immediately after the "50 sl." on the first output line. |
| | 117 | |
| | 118 | It is possible to adjust the parameters of the two directions of your link separately, to emulate asymmetric links. |
| | 119 | In this experiment, however, we are looking at symmetric links, so we'll always change the settings on both pipes together. |
| | 120 | |
| | 121 | Here are the command sequences you'll need to change your link parameters. |
| | 122 | In each case, you'll need to provide the correct pipe numbers, if they're different from the example. |
| | 123 | |
| | 124 | * To change bandwidth (10M means 10Mbits/s): |
| | 125 | {{{ |
| | 126 | sudo ipfw pipe 60111 config bw 10M |
| | 127 | sudo ipfw pipe 60121 config bw 10M |
| | 128 | }}} |
| | 129 | |
| | 130 | * Request a bandwidth of zero to use the full capacity of the link (unlimited): |
| | 131 | {{{ |
| | 132 | sudo ipfw pipe 60111 config bw 0 |
| | 133 | sudo ipfw pipe 60121 config bw 0 |
| | 134 | }}} |
| | 135 | |
| | 136 | * To change link delay (delays are measured in ms): |
| | 137 | {{{ |
| | 138 | sudo ipfw pipe 60111 config delay 10 |
| | 139 | sudo ipfw pipe 60121 config delay 10 |
| | 140 | }}} |
| | 141 | |
| | 142 | * To change packet loss rate (rate is a probability, so 0.001 means 0.1% packet loss): |
| | 143 | {{{ |
| | 144 | sudo ipfw pipe 60111 config plr .0001 |
| | 145 | sudo ipfw pipe 60121 config plr .0001 |
| | 146 | }}} |
| | 147 | |
| | 148 | * You can combine settings for bandwidth, delay, and loss by specifying more than one in a single ipfw command. We'll use this form in the procedure below. |
| | 149 | |
| | 150 | == Experiment Procedure == |
| | 151 | |
| | 152 | * Set your link parameters to use maximum bandwidth, no delay, no packet loss: |
| | 153 | |
| | 154 | {{{ |
| | 155 | sudo ipfw pipe 60111 config bw 0 delay 0 plr 0 |
| | 156 | sudo ipfw pipe 60121 config bw 0 delay 0 plr 0 |
| | 157 | }}} |
| | 158 | |
| | 159 | * Verify with |
| | 160 | |
| | 161 | {{{ |
| | 162 | sudo ipfw pipe show |
| | 163 | 60111: unlimited 0 ms 50 sl. 1 queues (1 buckets) droptail |
| | 164 | mask: 0x00 0x00000000/0x0000 -> 0x00000000/0x0000 |
| | 165 | BKT Prot ___Source IP/port____ ____Dest. IP/port____ Tot_pkt/bytes Pkt/Byte Drp |
| | 166 | 0 ip 207.167.175.72/0 195.123.216.8/6 7 1060 0 0 0 |
| | 167 | 60121: unlimited 0 ms 50 sl. 1 queues (1 buckets) droptail |
| | 168 | mask: 0x00 0x00000000/0x0000 -> 0x00000000/0x0000 |
| | 169 | BKT Prot ___Source IP/port____ ____Dest. IP/port____ Tot_pkt/bytes Pkt/Byte Drp |
| | 170 | 0 ip 207.167.176.224/0 195.124.8.8/6 8 1138 0 0 0 |
| | 171 | }}} |
| | 172 | |
| | 173 | Note that bandwidth is set to ''unlimited'', delay to ''0 ms'', and no PLR is shown. |
| | 174 | |
| | 175 | * Using this initial setting, try to transfer the files and note the rate of UDT and FTP. |
| | 176 | |
| | 177 | * Now change the link parameters to reduce the available bandwidth to 10Mbps: |
| | 178 | |
| | 179 | {{{ |
| | 180 | sudo ipfw pipe 60111 config bw 10M delay 0 plr 0 |
| | 181 | sudo ipfw pipe 60121 config bw 10M delay 0 plr 0 |
| | 182 | }}} |
| | 183 | |
| | 184 | * Repeat your file transfers with the new settings. As before, note the transfer sizes and rates, as well as the link settings. |
| | 185 | |
| | 186 | * Continue with additional trials, varying each of the three link parameters over a range sufficient to observe meaningful performance differences. Record your data. |
| | 187 | |
| | 188 | |
| | 189 | = 3. Delete your experiment = |
| | 190 | When we are done with our experiment it is always good to clean up and release our resources so other people can use them. |
| | 191 | {{{ |
| | 192 | #!html |
| | 193 | <table border="0"> |
| | 194 | |
| | 195 | <tr> |
| | 196 | <td> |
| | 197 | |
| | 198 | <img border="0" src="http://groups.geni.net/geni/attachment/wiki/GENIExperimenter/Graphics/delete-resources-portal.png?format=raw" alt="Create a GENI Project" height="90" title="Create a GENI Project" /> </a> |
| | 199 | </td> |
| | 200 | <td > |
| | 201 | <ol> |
| | 202 | <li> Go to the <i>Slices</i> tab. </li> |
| | 203 | <li> In your slice press the <b>Release Resources</b> button</li> |
| | 204 | |
| | 205 | </ol> |
| | 206 | </td> |
| | 207 | |
| | 208 | </tr> |
| | 209 | </table> |
| | 210 | }}} |
| | 211 | |
| | 212 | |
| | 213 | Congratulations you have successfully completed your first GENI assignment! |
| | 214 | |
| | 215 | = [wiki:NikySandbox/SIGSCETutorial/SetupAccount Previous Part: Setup your GENI account and your GENI Project] = |
