Chris Paquin

AI, Virtualization, Containers, Infrastructure, Linux

Category: Networking

  • HomeLab: Cisco 2621 Router Password Recovery/Factory Reset

    Cisco_2621_2So I was able to get my hands on a Cisco 2621 with a decently sized flash. I found out the hard way that some of these older routers have tiny flash memory drives that are too small to load any decent ios images on. Plus I found that in order to upgrade the flash memory, you also had to upgrade the bootrom. This chip and dimm combo runs about $30-$40. I was able to pick up this 2621 with 32mb flash (vs 8mb of my other 2621).

    So lets get the device up and running by resetting it to factory defaults.In order to accomplish this you need to boot to the rommon, which is accomplished by hitting the break sequence during the boot up process (specifically within 60 seconds).

    In minicom you accomplish this with the following key strokes.

    CTRL+A, F

    You will then see the following screen

    rommon 1 >

    Type the following to bypass startup files durring the boot process.

    rommon 1 > confreg 0x2142

    You will see the following message.

    You must reset or power cycle for new config to take effect

    Now do what it says, and type reset as show below.

    rommon 2 > reset

    The router will reboot and you will be prompted to enter the initial configuration dialog, choose no to this option.

    Now overwrite the saved config on the router with the command below.

    copy running-config
    startup-config

    Then run the following command so that at next boot you are not bypassing the startup files.

    router(config)#config-register 0x2102

    Now restart the router again and and the config will be wiped and passwords reset.

    Click here for the Cisco article that I used for reference.

  • HomeLab: Configuring the NTP Client on a Cisco Catalyst Switches

    Drinking-from-a-firehose-300x198First off let me start by saying that I am not sure that these commands only work on Catalyst switches, nor and I sure that these commands only work on switches, they may work on routers as well, however I have not gotten that far in my HomeLab escapades.

    What do know for a fact is that Cisco loves documentation, very, very verbose documentation, which honestly I cant say that I always have time or energy for. Cisco documentation is like drinking from a fire hose. Seriously I do not need to learn everything about this switch in one sitting.

    Anyway – lets talk about Time, Date, and NTP.

    To figure out what time your device thinks it is, use the command below.

    s-3560-1.localdomain>show clock
    12:58:28.929 CDT Wed Aug 21 2013

    To set the clock use the command below, subsitute the correct time dingbat

    s-3560-1.localdomain#clock set 12:58:28 21 Aug 2013

    In conf t mode you can configure an ntp server to sync with, see below.

    s-3560-1.localdomain(config)#ntp server 192.168.0.10

    You can also configure your device as an ntp peer, but we are not going to go into that here.

    To verify that you are now syncing with 192.168.0.10, use the command below.

    s-3560-1.localdomain#show ntp associations

      address         ref clock       st   when   poll reach  delay  offset   disp
     ~192.168.0.10    64.147.116.229   2     56     64     3  2.735 330586. 3937.9
     * sys.peer, # selected, + candidate, – outlyer, x falseticker, ~ configured

    To see a more detailed status for ntp use the command below.

    s-3560-1.localdomain#show ntp status
    Clock is unsynchronized, stratum 16, no reference clock
    nominal freq is 119.2092 Hz, actual freq is 119.2085 Hz, precision is 2**17
    reference time is D5BF7032.1462968F (12:58:26.079 CDT Wed Aug 21 2013)
    clock offset is 0.0000 msec, root delay is 0.00 msec
    root dispersion is 3.37 msec, peer dispersion is 0.00 msec
    loopfilter state is 'CTRL' (Normal Controlled Loop), drift is 0.000006336 s/s
    system poll interval is 64, last update was 227 sec ago.

     
    Related articles

    Standard Cisco Router Configuration Commands
    Find the Default IP of Your CISCO Router
    HomeLab: The Cisco 3560G
    cisco partner catalyst cisco

  • HomeLab: The Cisco 3560G

    WS-C3560G-24TSThe Cisco Catalyst 3506G is a layer 3 switch which went end-of-life in 2009. For the home lab its a pretty nice switch to have due to its layer 3 support and gigabit speed. Mine is the model seen to the left, 24 gigabit ports and 4x1gb SFP uplinks.

     

    The Cisco Catalyst 3560 is available with one of two software images:

    • IP Base software includes advanced quality of service (QoS),
      rate limiting, access control lists (ACLs), Open Shortest Path First
      (OSPF) for routed access, and IPv6 functionality.
    • IP Services software provides a broader set of
      enterprise-class features, including advanced hardware-based IP Unicast
      and IP Multicast routing, as well as policy-based routing (PBR).

    Anyway, gathered here are a few manadatory resources for the Cisco Catalyst 3560G.

    Related articles

    Vlan Configuration between Cisco & sonicwall help
    Cisco WS C3560X 24T L 3560X Catalyst Switch

  • Resources for the Cisco IOS/Nexus OS Newbie

    Ciscolive-hero2-200x200My visit to Cisco Live 2013 in Orlando this week has helped reinvigorate me in regards to getting off my tubby rear and dedicating some time to learning networking with Cisco devices.

    Previously my focus has purely been on Cisco UCS, however since my new company has me working with a lot of ancient Solaris Servers, and a good deal more IBM (AIX, PowerVM) than I am used to, there is not a great deal of use in me spending a lot of time learning UCS as it may be a few years before I get to lay hands on it again.

    However, on the plus side I have noticed that when it comes to certifications around UCS (which Cisco considers the datacenter track) I good deal more networking knowledge (CCNA level) seems to be required. And I get it… why not. Cisco touts UCS as a unified datacenter solution, so it makes sense that they want y0u to know your way around a router and a switch.

    Plus its not like I am a dummy in the area… I have spent more than my fair share of time showing a network administrator how to configure their equipment to connect to Vcenter, Xen, and RHEVH/M. Its just the command context that I struggle with.

    So I ordered a few used and cheap books and an planning to set aside some time to actually learn this very archaic operating system. Below are a few links that I either have already found useful, or hope to find useful in the near future.

  • How to Reset Cisco Catalyst 2960 Back to Factory Defaults

    Cisco-2960s-switchThis is my first post in what I hope to be a long line of Cisco networking related posts, as I have just gotten my hands on a bit of used Cisco equipment and hope to use it to setup a home lab.

    First step of setting up this home lab is to get my two Catalyst 2960s reset to factory defaults. So here is how you do it. Note that I am assuming that you have already established a console connection to the switch.

    First, boot up the switch while holding down the MODE button until you see the following appear on the screen.

    Switch>
Boot Sector Filesystem (bs) installed, fsid: 2
Base ethernet MAC Address: 00:17:0e:17:de:80
Xmodem file system is available.
The password-recovery mechanism is enabled.

The system has been interrupted prior to initializing the
flash filesystem.  The following commands will initialize
the flash filesystem, and finish loading the operating
system software:

    Then type flash_init

    switch: flash_init
    Initializing Flash...
    flashfs[0]: 547 files, 19 directories
    flashfs[0]: 0 orphaned files, 0 orphaned directories
    flashfs[0]: Total bytes: 32514048
    flashfs[0]: Bytes used: 15487488
    flashfs[0]: Bytes available: 17026560
    flashfs[0]: flashfs fsck took 11 seconds.
    ...done Initializing Flash.

    Check out the contents of flash and locate config.text and vlan.dat (if it exists).

    switch: dir flash:
Directory of flash:/

2  -rwx  564       <date>               vlan.dat
3  -rwx  1914      <date>               private-config.text
5  drwx  192       <date>               c2960-lanbasek9-mz.122-58.SE2
6  -rwx  3096      <date>               multiple-fs
7  -rwx  2289      <date>               config.text

    Now delete the vlan.dat and config.text.

    switch: del flash:config.text
Are you sure you want to delete "flash:config.text" (y/n)?y
File "flash:config.text" deleted

switch: del flash:vlan.dat
Are you sure you want to delete "flash:vlan.dat" (y/n)?y
File "flash:vlan.dat" deleted

    Now type boot, to reboot the switch. Once the switch is rebooted you will see the System Configuration Dialog, and will have the opportunity “to enter the initial configuration dialog”

    Additional Resources:

    http://www.cisco.com/c/en/us/support/docs/switches/catalyst-2900-xl-series-switches/24328-156.html

    http://www.cahilig.net/2014/04/14/how-reset-cisco-2960-switch-default-settings

    http://notthenetwork.me/blog/2013/05/28/reset-a-cisco-2960-switch-to-factory-default-settings/