Cisco 7603 configuration

Friday, April 13. 2007

Cisco 7603 configuration

Cisco WS-C2948 switch config

Wednesday, April 11. 2007

Cisco WS-2948 switch config

Upgrade the flash image on a Cisco 2514 router

Tuesday, April 10. 2007


  1. Enable TFTP in Solaris 10

    Comment in the following line in /etc/inetd.conf as follows:

    # TFTPD - tftp server (primarily used for booting)
    tftp dgram udp6 wait root /usr/sbin/in.tftpd in.tftpd -s /tftpboot


    Apply the change:

    bash-3.00# inetconf

    Check that the TFTP server is running:

    bash-3.00# svcs | grep tftp
    online 17:32:25 svc:/network/tftp/udp6:default


    Create /tftpboot directory and make it world RW:

    bash-3.00# mkdir /tftpboot
    bash-3.00# chmod 777 /tftpboot


  2. PUT the flash image on the TFTP server

    View the flash image on the [source] router:

    router101#show flash:

    System flash directory:
    File Length Name/status
    1 7923420 c2500-i-l.121-9
    [7923484 bytes used, 465124 available, 8388608 total]
    8192K bytes of processor board System flash (Read ONLY)


    Create an empty file with the same name and make it world RW:

    bash-3.00# touch /tftproot/c2500-i-l.121-9
    bash-3.00# chmod 777 /tftproot/c2500-i-l.121-9


    Upload the flash image:

    router101#copy flash tftp
    Source filename []? c2500-i-l.121-9
    Address or name of remote host []? 192.168.1.100
    Destination filename [c2500-i-l.121-9]?
    !!!!!!!!!!!!!!!!!!!!!!!!....
    7923420 bytes copied in 110.328 secs (72031 bytes/sec)


  3. GET the flash image from the TFTP server

    router100(boot)#copy tftp flash

Reset Cisco device passwords

Monday, April 2. 2007

Here is how to reset the passwords on a Cisco switch/router:


  • Power on the device.
  • Stop the boot sequence by sending Control-Break from Hyperterminal within the first few seconds.
    Abort at 0x11198B4 (PC)
  • Make a note of the current configuration register, it probably is 0x2102
    >o
    Configuration register = 0x2142 at last boot
    Bit# Configuration register option settings:
    15 Diagnostic mode disabled
    14 IP broadcasts do not have network numbers
    13 Boot default ROM software if network boot fails
    12-11 Console speed is 9600 baud
    10 IP broadcasts with ones
    08 Break disabled
    07 OEM disabled
    06 Ignore configuration enabled
    03-00 Boot file is cisco2-2500 (or 'boot system' command)

  • Bypass the NVRAM configuration.
    o/r 0x2142
  • During the subsequent reboot, answer 'no' to any configuration prompts
  • Enter 'enable' mode which now does not require a password, and reset any desired passwords
  • After the changes are written to the configuration, power cycle the device and set the configuration register back to 0x2102

CNR on Ubuntu

Tuesday, February 13. 2007

With a few minor changes, CNR for Red Hat Linux 7.3 can be installed on Ubuntu.


  1. Install RPM

    sudo apt-get install rpm

  2. Edit install_cnr, adding --nodeps to the following line:

    rpm --nodeps -U --replacefiles --replacepkgs .........

  3. Create directories

    mkdir /etc/rc.d
    mkdir /etc/rc.d/init.d
    mkdir /etc/rc.d/rc0.d
    mkdir /etc/rc.d/rc1.d
    mkdir /etc/rc.d/rc2.d
    mkdir /etc/rc.d/rc3.d
    mkdir /etc/rc.d/rc4.d
    mkdir /etc/rc.d/rc5.d


  4. Install awk

    sudo apt-get install gawk
    ln -s /usr/bin/awk /bin/awk

Packet Capture

Thursday, February 8. 2007

The SPAN feature configuration commands are similar on the Catalyst 2950 and Catalyst 3550. However, the Catalyst 2950 cannot monitor the VLANs. You can configure the SPAN, as in this example:

C2950#configure terminal
C2950(config)#
C2950(config)#monitor session 1 source interface fastethernet 0/2

!--- This configures interface Fast Ethernet 0/2 as source port.

C2950(config)#monitor session 1 destination interface fastethernet 0/3

!--- This configures interface Fast Ethernet 0/3 as destination port.

C2950(config)#

C2950#show monitor session 1
Session 1
---------
Source Ports:
RX Only: None
TX Only: None
Both: Fa0/2
Destination Ports: Fa0/3
C2950#

Catalyst 2950 Switch Config

Thursday, October 19. 2006

Catalyst 2950 Switch Config

Cisco 2500 Router Config

Thursday, October 19. 2006

Cisco 2500 Router Config

Debug SNMP traffic

Friday, October 6. 2006

To view SNMP traffic from a Cisco device:

telnet router
Password:
router>en
Password:
router#en
router#terminal monitor
router#debug snmp requests


To turn off SNMP debugging:

router#no debug snmp request

To turn off ALL debugging:

undebug all

Cisco 2950 Switch Configuration

Friday, May 5. 2006

From the console:

# start with a clean slate:
erase startup-config
reload

Would you like to enter the initial configuration dialog? [yes/no]: no

en
conf t

# set passwords
enable secret "secret here"
enable password "password here"

# turn on telnet
line vty 0 15
password "password here"
exit

# set network
interface vlan1
ip address "ip address here" 255.255.255.0
no shut
exit

exit
write memory

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

That is it from the console. Now connect to switch via telnet:

# enable SNMP
conf t
snmp-server community public rw

# enable Option 82
ip dhcp snooping
ip dhcp snooping vlan 1
interface FastEthernet 0/1
ip dhcp snooping trust
exit
exit
write memory

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

To enable SNMP traps:

snmp-server host "host ip address here" traps version 2c public
snmp-server enable traps snmp linkdown linkup