HP AdvanceStack Hubs

 

Aims:

  • To discover how to configure and use a network device
  • To investigate SNMP services and management tools for the HP AdvanceStack hub

Resources:

  1. Access to internet for searching and download
  2. Knoppix bootable CD or previously formatted Fedora disk
  3. HP J3202A Advancestack hub + HPJ3210A SNMP module
  4. UTP cables
  5. HP Advancestack reference manual (ftp://ftp.hp.com/pub/networking/software/59644662.pdf)
  6. scli (in Knoppix) or net-snmp (snmpget/set/walk in Fedora) software
  7. Web browser with Java support
  8. Network Management and Monitoring with Linux by David Guerrero
  9. SNMP links from FIT2018 Resource page

Exercises:

  1. For this Lab exercise you will need to form a group of students around a cluster of PCs in the Lab and in this context some cooperative activity and joint completion of questions and demonstrations for this exercise is encouraged.

  2. Make a list of the MAC addresses of the ethernet cards of all your PCs and the HP Hub. MAC addresses can be listed using:  IPCONFIG /ALL  or  Network|Connection|Status  in windows or using:  ifconfig -a eth0  in linux.

  3. Disconnect your PCs from the monash network and boot Knoppix from CDROM or Fedora from disk, on one PC. Configure that PC with a fixed IP address (eg 192.168.10.1)

  4. On that PC, configure a DHCP server (as described in previous Tutorial exercsises) which can be used to do IP configuration in a private network. In addition to the other PC in your Lab network, the management agent in the HP hub is configured to acquire an IP address using BOOTP or DHCP, so you will need to arrange so that your DHCP server will configure all these IP addresses. When asked to do so, describe the method you used to your tutor.benchtop network
  5. With the Hub turned off and after the DHCP server is running, plug all your PCs into neighbouring ports of the HP hub, starting with port 1, as shown above. Now turn on the power for the Hub and then boot the other PCs. They should acquire an IP number from your DHCP server. After the boot of each PC is complete, verify the IP setup using PING commands. Show the working PING commands to your Tutor.
  6. Ascertain the IP number that was given to your HP hub. (Hint: look in the server logfile of the machine that is running the DHCP server). Verify that the HP hub is working and connected using PING. The IP address of your hub's management interface will be shown in the steps below as "[HubIP]".

  7. Verify that the SNMP management is operational using a SNMP command to display the "system" MIB objects, such as SysName, SysContact and SysLocation. Note that the SNMP agent running in these HP hubs recognises SNMP version 1 and 2c and has a single open (writable) community called "PUBLIC". Write down the command used and the values of the SNMP system variables in the table shown below:

SNMP Utility command:

MIB object Observed OID value
sysDescr.0

sysName.0

sysContact.0

sysLocation.0

  1. Using one PC, enter the command: telnet [HubIP]. After a short delay, the telnet window should display a management interface dialog. Enter the "HELP" command to find out about the options available. Enter the "MENU" command to begin a management session (if there are several hubs in the stack, you may need to identify which one you wish to configure). The telnet interface uses a heirarchical numeric menu system where menu choices are indicated by entering the number of that choice. Usually the number "0" will exit to the previous menu level. Choosing option "0" at the top level will exit from the telnet session. You may also enter Ctrl-] to exit at any time.
    WARNING:
    Dont change any settings, especially the community name (PUBLIC), port-segment assignments or the IP configuration of the Hub.
  2. In the Telnet session, from the  Main Menu, select option (1) Hub Status and Counters... In the Hub Status and Counters menu, select option (1) Display general status information.... Enter "Y" in response to the question "change any of the system information"... and enter "C" to change the Contact Information field. Which field in the standard MIB do you think this is altering???

  3. On one PC start a web browser. Configure the proxy setting for "Direct connection to network". Using the web browser, enter the [HubIP] as a URL. After a short delay (during which some java applets will be started) you should see:HP J3210A management Web Interface
    If the screen does not appear as shown above, this may be because the java applets are unavailable.

  4. Click on the "Identity" tag and verify that the System Contact value is the one that was set in the earlier step.

  5. On another PC use the command:  sudo ping -f IPnumber  to generate lots of data traffic!! Now monitor the segment utilization and performance gauges displayed in the previous Hub Management web pages.

  6. For the purposes of monitoring traffic, you will need to setup a situation where large amounts of network traffic is forwarded through the hub. One way to generate traffic is to start an FTP server on one machine and run an FTP client on another, which repeatedly uploads and downloads files of various sizes. Try this test if time is available, and observe the statistics kept by the SNMP agent in the hub....

  7. Another way to generate continuous traffic is to activate the echo (TCP port 7) and chargen (TCP port 19) services in a linux environment on one PC, and use piped telnet commands on another PC to create continuous traffic. To activate these services in KNOPPIX (eg on a machine called PC1):

    1. Edit the file /etc/inetd.conf and uncomment the lines associated with echo and chargen.
    2. Restart the internet superserver using the command:  sudo /etc/init.d/inetd restart
    3. On another machine (eg PC2) also connected to the same hub, enter the command telnet PC1 19|telnet PC1 7
The telnet to port 19 on PC1 uses the chargen service as a continuous source of text, which is then piped into the connection to the echo service back on PC1, which then sends the data back to PC2. In this way, a continuous stream of characters is traversing the hub in both directions.
  1. What are the maximum data rates (in Bits/sec and Packets/sec) achieved using the traffic generation methods mentioned above?
    What are these values as a percentage of the total bandwidth of the network (ie as a % of 10Mbps)?