Network Testing Tools. Ettore Tamiro GARR - Network Operation Center PAP Workshop July 15, 2009

Transcription

1 Network Testing Tools Ettore Tamiro GARR - Network Operation Center PAP Workshop July 15, 2009

2 This tutorial is based on a previous work by For the Rich Carlson NWS Workshop Jan 12-14, 2009 Installing a perfsonar Network Performance Node 2

3 Introduction First question: Why do we need network testing tools? 3

4 Introduction Healthy networks are the basis for a good user experience Network issues that may be not perceptible using certain applications, can be very annoying for other specific services or can even be the source of severe problems This is more true for networks intended to offer multimedia services 4

5 Introduction Second question: What do we are searching for? 5

6 Introduction Congested links Queuing problems ( Jitter ) Packet Delay Variations Packet Loss 6

7 Introduction Third question: What all of these problems have in common? 7

8 Introduction At least one thing: They are hard to investigate! And even worst: they are harder to discover in a multi-domain environment 8

9 Introduction Fourth question: Are we all alone or out there we can find something to help us in our quest? 9

10 Introduction Internet2 has built a live Linux distro With a built-in set of network testing tools 10

11 Introduction Most of the Internet2 network performance tools are client/server based Client software runs on the users Laptop/Desktop computer Software is automatically downloaded when a test is requested Server software runs on a dedicated server which is physically attached to the network on the same LAN as the production server Software is pre-installed and must be customized before using 11

12 Initial Suite of Tools NDT a client/server program to find host configuration and network infrastructure faults NPAD a client/server program to verify host configuration and local infrastructure will work with remote sites BWCTL a client/server program to continuously monitor the network infrastructure OWAMP a client/server program to continuously monitor the end-to-end delay 12

13 perfsonar A framework for building large scale, multi-domain network measurement and monitoring infrastructures Reference implementations of tools that use this framework have been developed by Internet2 engineers to demonstrate the value of this approach 13

14 perfsonar perfnode A pre-built ISO image that can be booted to quickly bring up a measurement server Initial boot requires configuration and ( presentation customization steps (this Subsequent boots bring the system back to this known state Most of the data in this slide deck comes from the on-line quick-start guide by Jason Zurawski 14

15 Step 1 Obtain the ISO image Download the latest ISO image from OR, ask Internet2 staff to send you a CD- ROM disk Burn the downloaded ISO image onto a CD-ROM disk Be sure and burn this as an ISO image and not as a data disk, see the instructions for your burner software. 15

16 Step 2 Prepare the Hardware Find a computer you can dedicate as a server 1.8 GHz Intel/AMD processor 512 MB RAM ( formatted 80 GB Hard disk (Disk needs to be 100 Mbps Ethernet interface CD read-only disk drive Note: a low-cost rack-mount server is available from KOI computers for approximately $600, contact Internet2 staff for details 16

17 Step 3 (a) Initial Boot BIOS setup Once you have obtained a setup cd-rom, be sure that your server is configured to boot first from removable media. This is done by manipulating the boot device priority in the BIOS settings Be aware that dealing with the BIOS is a risky task, so If you feel unsure, ask for help 17

18 Step 3 (b) Initial Boot Insert the CD-ROM disk into the drive and power on the system. The following screen will appear. Press Enter or wait 30 seconds for boot process to begin 18

19 Step 4 Begin Configuration After a short time, the following screen will appear. All items in RED need to be configured. 19

20 Step 5 (a) Begin Configuration BE CAREFULL AT THIS STEP! perfsonar perfnode uses a mass storage unit to hold both collected data And configuration settings. You will be prompted to specify this unit and a wrong selection could Make you loose all of the data stored on your computer HD! You have been provided with a 2GB usb disk that will be used as installation Unit. If unsure on which unit to select during the setup process, don t esitate to ASK! 20

21 Step 5 (b) Select a Drive Enter 1 to configure the Drive information 21 In this case only 1 drive is available, select the drive listed on your server Note: the drive will be reformatted if necessary

22 Step 6 Configure Site Settings Select 2 to enter the Site Settings option Enter admin s name/ , org name and physical location, and the link speed, use PAPW as the communities of interest 22

23 Step 7 Enter passwords Enter 3 to set the system passwords, you will not be able to use the system if you don t set these passwords 23

24 Step 8 Configure specific services Enter 4 to enable/disable specific services Enable NDT, NPAD, BWCTL, OWAMP and Web Service Enable SSH only if you want to remotely login to this server Disable PingER, SNMP, and perfsonar-buoy services 24

25 Step 9 Manage Users Skip this item, unless you specifically need to add a new user, you can skip this item! 25

26 Step 10 Configure BWCTL Enter 6 and press Enter when prompted. Simply take the default settings 26

27 Step 11 Configure NTP You are in a closed LAN so enter 7, then simply enter 0 to exit this page. For a production system you can obtain better servers from your campus IT staff 27

28 Step 12 Configure OWAMP Enter 8 and then press Enter when prompted to take the default values 28

29 Step 13 Configure Static IP address In most cases your campus will automatically assign an IP address to the server during the boot process but For this tutorial provide the IP address and NETMASK that you have received from the PAPW staff 29

30 Step 14 Enter timezone info An optional step to set the timezone for your physical location. 30

31 Step 15 Modify advertised interface Skip this item. In most cases your server will have only 1 network interface so you can skip this task. 31

32 Configuration Complete Once you have configured all these items, Press 0, the system may reboot, or it may just continue on and complete the boot process. When the boot process is complete you will receive a login prompt. ( quotes The login id is knoppix (no The password is what you assigned 32

33 33 User Login Complete

34 Verify IP address Enter the command ifconfig to verify IP address is configured and operational 34

35 Start KDE desktop environment Enter the command startx 35

36 36 Java support In the real world you don t need Java to run on your server because it is required only by ( browser the client hosts (the one with the But, given that you have only one PC for this tutorial, you need to run a server and a client on the same machine GARR has made available a web server in this LAN with everything needed for a ( ) painless Java setup Once Java will be installed you can test your server or those of your collegues

37 Verify Operation Bring up a web browser and enter where {ip-address} is the address assigned to this server in the w.x.y.z format If your IT department has assigned a DNS name to this address you can use that name instead. 37

38 38 Main Server Web page

39 Finding other Server The Global Set Of Services link gets you to a new page that lists your peer servers. All remote servers should be listed, servers run by peer PAPW sites will appear under the PAPW heading 39

40 40

41 Server Status Your server is now ready to support testing You can point clients to it so verify your site is operating properly You can point clients to the remote site to verify that the WAN path is capable of carrying your traffic 41

42 Running NDT test Press Start Button 42

43 Running NPAD test Test to Local server and enter required speed and RTT to remote location then press start 43

44 Conclusion Server should be permanently installed at your home institution on your local network Once the ISO image is booted, the tools will register with a global lookup service so others can find them These tools will make it easier to find and fix network performance problems 44