Changes between Version 9 and Version 10 of ConnectivityTesting


Ignore:
Timestamp:
12/02/10 15:24:08 (13 years ago)
Author:
jwilliams@bbn.com
Comment:

added notes about arping

Legend:

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  • ConnectivityTesting

    v9 v10  
    22[[PageOutline]]
    33
    4 '''FIRST-CUT NETWORK TOOLS AND CONFIGURATION FOR TESTS BETWEEN GPO LAB AND CAMPUSES'''
    5 
    6 Below are a few network tools currently supported by the GPO Lab for testing purposes.  Should your campus decide to test with BBN, please note the tool, and its respective configurations (NB. These configurations were tested on Ubuntu 10.04). The statistics obtained will be available to the public via our monitoring web-server and will prove effective in determining the operational status of GENI connections.
     4'''DRAFT NETWORK TOOLS AND CONFIGURATION FOR TESTS BETWEEN GPO LAB AND CAMPUSES'''
     5
     6Below are a few network tools currently supported by the GPO Lab for testing purposes.  Should your campus decide to test with the GPO, please note the tool, and its respective configurations (NB. These configurations were tested on Ubuntu 10.04). The statistics obtained will be available to the public via our monitoring web-server and will prove effective in determining the operational status of GENI connections.
    77
    88For a template for informing a campus of requirements of a test host to support this testing see PersistentTestHostRequirments.
    99
    1010== traceroute ==
     11For GENI, this is used to verify that the route configuration is correct over a GENI backbone connection, which should be a single broadcast domain. I.E., a single hope should be displayed.  For example, the GPO's connection to Rutgers via I2's ION service only has one hop.
     12{{{
     13[jwilliams@argos ~]$ traceroute 10.37.33.101
     14traceroute to 10.37.33.101 (10.37.33.101), 30 hops max, 40 byte packets
     15 1  probe1-vlan3733.rutgers.dataplane.geni.net (10.37.33.101)  32.200 ms  32.250 ms  32.287 ms
     16[jwilliams@argos ~]$
     17}}}
    1118
    1219== tcpdump ==
     20Useful for capturing and analogizing network traffic. Documentation and download from http://www.tcpdump.org/.
    1321
    1422== arping ==
     23Simular to ping, but works at layer-2. Hoever sudo access is requiresd and, typically you'll specify your physical interface. Arping is useful for :
     24
     25 * detecting duplicate IP addresses. The Example below shows to hosts, deliniated by MAC, reporting the same IP address.
     26{{{
     27[jwilliams@carthage ~]$ sudo /sbin/arping 10.37.5.101 -I eth7
     28ARPING 10.37.5.101 from 10.37.5.100 eth7
     29Unicast reply from 10.37.5.101 [00:0C:29:9D:65:D7]  0.900ms
     30Unicast reply from 10.37.5.101 [00:16:B9:CF:FC:40]  30.330ms
     31}}}
     32 * generating layer-2 traffic to a given IP address. This allows for switches's MAC-port tables to be inspected for your known path to identify a problem. the example below shows the GPO's MAC showing up in the NLR's Boston switch but not NLR's Seattle switch, which helped diagnose the problem.
     33{{{
     34# display our MAC
     35[jwilliams@wyverley ~]$ /sbin/ifconfig eth3 | grep HWaddr
     36eth3      Link encap:Ethernet  HWaddr 00:0C:29:40:45:1D 
     37
     38#generate layer-2 traffic from this MAC
     39[jwilliams@wyverley ~]$ sudo /sbin/arping -I eth3 10.37.16.90
     40ARPING 10.37.16.90 from 10.37.16.100 eth3
     41
     42#NLR's Boston switch - shows our MAC:
     43  vlan   mac address     type    learn     age              ports
     44------+----------------+--------+-----+----------+--------------------------
     45* 3716  000c.2940.451d   dynamic  Yes          0   Gi9/2
     46* 3716  001b.902e.f4ca   dynamic  Yes         60   Te1/2
     47
     48#NLR's Seattle switch - does NOT show our MAC:
     49  vlan   mac address     type    learn     age              ports
     50------+----------------+--------+-----+----------+--------------------------
     51* 3716  3333.0000.0016    static  Yes          -   Switch,Stby-Switch
     52}}}
     53
    1554
    1655== iperf ==
     
    86125
    87126=== Generating traffic with VLC ===
    88 
    89127For this test, the video server streams UDP packets to the client who stores the stream  in a file (Perhaps for later viewing). This test primarily analyzes performance statistics (using tcpdump) rather than viewing the stream on the client side. 
    90128