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Networking

  • Comments About Networking Technology


    We've noticed in many ways that traditional networking even in WANs and LANs has changed very little.  Years ago most networks were running on 100mbit and today most still are.

    Even the average internet connection is largely unchanged from several years ago with some minor exceptions from Europe and Asia.


  • HP Procurve Switch 2824 CLI Telnet Experience , Guide and Tutorial


    telnet 192.168.1.54
    -------------------------------------
    ProCurve J4903A Switch 2824
    Software revision I.10.77

    Copyright (C) 1991-2009 Hewlett-Packard Co.  All Rights Reserved.

                               RESTRICTED RIGHTS LEGEND

     Use, duplication, or disclosure by the Government is subject to restrictions
     as set forth in subdivision (b) (3) (ii) of the Rights in Technical Data and
     Computer Software clause at 52.227-7013.

             HEWLETT-PACKARD COMPANY, 3000 Hanover St., Palo Alto, CA 94303

    We'd like to keep you up to date about:
      * Software feature updates
      * New product announcements
      * Special events

    Please register your products now at:  www.ProCurve.com




    Press any key to continue
    -------------------------------------------

    LACP Problems - Be Warned - Disable LACP Unless You Need It!

    Disable LACP, this is the link aggregation protocol where you can combine 4 ports to increase the overall bandwidth.  This sure sounds great but all LACP ports should be disabled unless you are using it. The reason is because it often takes down ports of computers/servers for no apparent or justified reason and it is a pain to troubleshoot.  LACP should only be enabled on ports that are actually going to use LACP.

    Symptoms in the log are as follows:

    I 01/02/90 01:41:36 ports: port 7 is Blocked by LACP
    I 01/02/90 01:41:39 ports: port 7 is now on-line
    I 01/02/90 01:45:23 ports: port 7 is now off-line
    I 01/02/90 01:45:48 ports: port 7 is Blocked by LACP
    I 01/02/90 01:45:51 ports: port 7 is now on-line
    I 01/02/90 01:56:47 ports: port 7 is now off-line
    I 01/02/90 02:22:42 ports: port 7 is Blocked by LACP
    I 01/02/90 02:22:42 ports: port 7 is now off-line
    I 01/02/90 02:39:44 ports: port 7 is Blocked by LACP
    I 01/02/90 02:39:47 ports: port 7 is now on-line
    I 01/02/90 02:45:15 ports: port 7 is now off-line
    I 01/02/90 02:56:42 ports: port 7 is Blocked by LACP
    I 01/02/90 02:56:45 ports: port 7 is now on-line
    I 01/02/90 02:57:44 ports: port 7 is now off-line

    #check if you have lacp enabled on any ports


    show lacp
    no LACP ports found.

    How to disable LACP:

    *Warning if you have machines that do not come back automatically if the link goes up and down be warned that this could take some or all machines offline and needs physical intervention.  When I typed the "no interface all lacp" this took down most computers on the switch and they did not come back on their own except a few.


    ProCurve Switch 2824# config
    ProCurve Switch 2824(config)#
    ProCurve Switch 2824(config)# no interface all lacp
    wr mem



     

     

    Disable port

    *Warning about port disable/enable is that I find some servers detect the uplink but will not work after being re-enabled without a network restart (eg. service network restart

    The "8" represents port numbers.  You can also do a range such as "8-15"

    config

    int ethernet 8 disable

    ---------------------------

     

    Enable Port

    *Warning about port disable/enable is that I find some servers detect the uplink but will not work after being re-enabled without a network restart (eg. service network restart

    config

    int ethernet 8 enable

    ------------------------------------

    Check each port's bandwidth usage in mbit

    The "Util" field is how many mbit per second the port is doing.  You need to base the % percentage off the port speed eg. 10,100 or 1000 mbit. 

     Port      Mode     | --------------------------- | ---------------------------
                        | Kbits/sec   Pkts/sec  Util  | Kbits/sec  Pkts/sec   Util
     --------- -------- + ---------- ---------- ----- + ---------- ---------- -----
     1         1000FDx  | 5016       15         00.50 | 5040       47         00.50
     2         1000FDx  | 0          0          0     | 0          0          0   
     3         1000FDx  | 2536       0          00.25 | 5024       32         00.50
     4         1000FDx  | 12376      691        01.23 | 5352       448        00.53
     5         1000FDx  | 600        0          00.06 | 5024       32         00.50
     6         1000FDx  | 3960       0          00.39 | 5024       32         00.50
     7         1000FDx  | 5360       77         00.53 | 5344       112        00.53
     8         1000FDx  | 0          0          0     | 0          0          0   
     9         1000FDx  | 2488       0          00.24 | 5024       32         00.50
     10        1000FDx  | 2536       0          00.25 | 5024       32         00.50
     11        1000FDx  | 2488       0          00.24 | 5024       32         00.50
     12        1000FDx  | 2472       0          00.24 | 5024       32         00.50
     13        1000FDx  | 0          0          0     | 0          0          0   
     14        1000FDx  | 0          0          0     | 0          0          0   
     15        1000FDx  | 0          0          0     | 0          0          0   
     16        1000FDx  | 0          0          0     | 0          0          0   
     17        1000FDx  | 0          0          0     | 0          0          0   
     18        1000FDx  | 0          0          0     | 0          0          0   
     19        1000FDx  | 5680       538        00.56 | 12760      784        01.27
     20        100HDx   | 0          0          0     | 520        32         00.52
     21        1000FDx  | 0          0          0     | 0          0          0   
     22        1000FDx  | 0          0          0     | 0          0          0   
     23        1000FDx  | 0          0          0     | 0          0          0   
     24        1000FDx  | 0          0          0     | 0          0          0   

    -------------------------------------------------------------

    Show What Port MAC Address Belongs To

    show mac 00:1F:D0:00:13:CC

     Status and Counters - Address Table - 001fd0-0013cc

      MAC Address : 001fd0-0013cc
      Located on Port : 8  

    Show All MAC Addresses By Port

    show mac all

    If no MAC is displayed it means no device is connected or the device is not active or the port on the switch may be bad or disabled.

     Status and Counters - Port Address Table - 17

      MAC Address 
      -------------
      

    show specific port mac

    show mac 10

     

    Check overall port status

    show interfaces is very useful for counting traffic and also identifying network issues

     Status and Counters - Port Status

                      | Intrusion                           MDI   Flow  Bcast
      Port  Type      | Alert     Enabled Status Mode       Mode  Ctrl  Limit
      ----- --------- + --------- ------- ------ ---------- ----- ----- ------
      1     100/1000T | No        Yes     Up     1000FDx    MDIX  off   0    
      2     100/1000T | No        Yes     Down   1000FDx    MDIX  off   0    
      3     100/1000T | No        Yes     Up     1000FDx    MDI   off   0    
      4     100/1000T | No        Yes     Up     1000FDx    MDIX  off   0    
      5     100/1000T | No        Yes     Up     1000FDx    MDIX  off   0    
      6     100/1000T | No        Yes     Up     1000FDx    MDI   off   0    
      7     100/1000T | No        Yes     Up     1000FDx    MDI   off   0    
      8     100/1000T | No        No      Down   1000FDx    MDI   off   0    
      9     100/1000T | No        Yes     Up     1000FDx    MDI   off   0    
      10    100/1000T | No        Yes     Up     1000FDx    MDI   off   0    
      11    100/1000T | No        Yes     Up     1000FDx    MDI   off   0    
      12    100/1000T | No        Yes     Up     1000FDx    MDI   off   0    
      13    100/1000T | No        Yes     Down   1000FDx    MDI   off   0    
      14    100/1000T | No        Yes     Down   1000FDx    MDI   off   0    
      15    100/1000T | No        Yes     Down   1000FDx    MDIX  off   0    
      16    100/1000T | No        Yes     Down   1000FDx    MDIX  off   0    
      17    100/1000T | No        Yes     Down   1000FDx    MDIX  off   0    
      18    100/1000T | No        Yes     Down   1000FDx    MDIX  off   0    
      19    100/1000T | No        Yes     Up     1000FDx    MDIX  off   0    
      20    100/1000T | No        Yes     Up     100HDx     MDIX  off   0    
      21    100/1000T | No        Yes     Down   1000FDx    MDIX  off   0    
      22    100/1000T | No        Yes     Down   1000FDx    MDI   off   0    
      23    100/1000T | No        Yes     Down   1000FDx    MDI   off   0    
      24    100/1000T | No        Yes     Down   1000FDx    MDIX  off   0  

     

    show interfaces gives you more detail

     

    Notice Port 7 showing 203 "Errors Rx".  It was because of a bad cable and we wondered why that server had spotty connectivity.

     Status and Counters - Port Counters

                                                                Flow  Bcast
      Port  Total Bytes  Total Frames Errors Rx    Drops Rx     Ctrl  Limit
      ----- ------------ ------------ ------------ ------------ ----- ------
      1     3,164,403... 2,285,255... 0            0            off   0    
      2     457,687,164  2,150,118... 0            0            off   0    
      3     3,716,409... 2,795,214... 14           0            off   0    
      4     1,897,977... 2,207,705... 0            0            off   0    
      5     626,012,466  3,843,597... 0            0            off   0    
      6     2,628,057... 2,138,559... 0            0            off   0    
      7     1,498,582... 476,790,025  0            0            off   0    
      8     2,830,274... 1,696,622... 589          0            off   0    
      9     1,573,201... 3,990,337... 0            0            off   0    
      10    1,930,438... 2,808,292... 238          0            off   0    
      11    3,137,823... 3,577,438... 1476         0            off   0    
      12    2,363,525... 99,291,760   1102         0            off   0    
      13    0            0            0            0            off   0    
      14    0            0            0            0            off   0    
      15    0            0            0            0            off   0    
      16    0            0            0            0            off   0    
      17    0            0            0            0            off   0    
      18    0            0            0            0            off   0    
      19    2,186,889... 2,963,434... 1            0            off   0    
      20    530,240,341  746,865,357  581          0            off   0    
      21    1866         7            2            0            off   0    
      22    2288         7            2            0            off   0    
      23    2246         7            2            0            off   0    
      24    190,610      1821         2            0            off   0
     

    Password Issues/Requirements

    Note that these switches support a maximum of 16 characters.  Spaces cannot be used and it is not obvious if you have gone over the limit so if you cannot login after setting a password type it out and count 16 characters and use only those and you should be able to login.

    If your password is lost/unknown you can reset just the password (not the switch settings) by holding the "Clear" button on the front of the switch for at least 1 second.  Note again this does not reset the switch config but only the password when done this way.


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