Saturday 11 April 2015

Cisco Switch password recovery

CISCO SWITCH PASSWORD RECOVERY



Step-by-Step Procedure

Follow the password recovery procedure below.
1.    Attach a terminal or PC with terminal emulation (for example, Hyper Terminal) to the console port of the switch.
·         Use the following terminal settings:
·         Bits per second (baud): 9600
·         Data bits: 8
·         Parity: None
·         Stop bits: 1
·         Flow Control: Xon/Xoff
2.    POWER CYCLE SWITCH
3.    Power the switch and bring it to the switch: prompt:
For 2900XL, 3500XL, 2940, 2950, 2960, 2970, 3550, 3560, and 3750 series switches, do this: Hold down the mode button located on the left side of the front panel, while you reconnect the power cable to the switch.


Catalyst Switch Series
LED Behavior and Mode Button Release Action
2900XL, 3500XL, 3550
Release the Mode button when the LED above Port1x goes out.
2940, 2950
Release the Mode button after approximately 5 seconds when the Status (STAT) LED goes out. When you release the Mode button, the SYST LED blinks amber.
2960, 2970
Release the Mode button when the SYST LED blinks amber and then turns solid green. When you release the Mode button, the SYST LED blinks green.
3560, 3750
Release the Mode button after approximately 15 seconds when the SYST LED turns solid green. When you release the Mode button, the SYST LED blinks green.

4.    Issue the flash_init command.

switch: flash_init
Initializing Flash...
flashfs[0]: 82 files, 3 directories
flashfs[0]: 0 orphaned files, 0 orphaned directories
flashfs[0]: Total bytes: 7741440
flashfs[0]: Bytes used: 5983744
flashfs[0]: Bytes available: 1757696
flashfs[0]: flashfs fsck took 7 seconds.
...done initializing flash.
Boot Sector Filesystem (bs:) installed, fsid: 3
Parameter Block Filesystem (pb:) installed, fsid: 4

5.    Issue the load_helper command.

Issue the load_helper command.
switch: load_helper
switch:

6.    Issue the dir flash: command.


Issue the dir flash: command.
Note: Make sure to type a colon ":" after the dir flash.
switch: dir flash:
Directory of flash:/

2    -rwx  2980731   <date>               c2950-i6q4l2-mz.121-19.EA1c.bin
3    -rwx  269       <date>               env_vars
4    -rwx  796       <date>               vlan.dat
5    -rwx  1478      <date>               config.old
6    -rwx  5         <date>               private-config.text
7    -rwx  110       <date>               info
8    drwx  2432      <date>               html
85   -rwx  110       <date>               info.ver

1757696 bytes available (5983744 bytes used)
!--- This output is from a 2950  switch. Output from
!--- other switches will vary slightly.


Type rename flash:config.text flash:config.old to rename the configuration file.
switch: rename flash:config.text flash:config.old
switch:

!--- The config.text file contains the password
!--- definition.


8.    Issue the dir flash: command.


Issue the dir flash: command.
Note: Make sure to type a colon ":" after the dir flash.
The switch file system is displayed:
switch: dir flash:
2    -rwx  2980731   <date>               c2950-i6q4l2-mz.121-19.EA1c.bin
3    -rwx  269       <date>               env_vars
4    -rwx  796       <date>               vlan.dat
5    -rwx  1478      <date>               config.old
6    -rwx  5         <date>               private-config.text
7    -rwx  110       <date>               info
8    drwx  2432      <date>               html
85   -rwx  110       <date>               info.ver


!--- This output is from a 2950 switch. Output from
!--- other switches will vary slightly.

9.    Issue the boot command.

Issue the boot command to boot the system.
switch: boot
switch: boot
Loading "flash:/c2950-i6q4l2-mz.121-19.EA1c.bin"...##################################################################################################################################################################################################################################################################################################

10. Issue the no  command at the initial dialog prompt

Enter "n" at the prompt to abort the initial configuration dialog.
--- System Configuration Dialog ---
At any point you may enter a question mark '?' for help.
Use ctrl-c to abort configuration dialog at any prompt.
Default settings are in square brackets '[]'.
Continue with configuration dialog? [yes/no]: n

!--- Type "n" for no.

Press RETURN to get started.

!--- Press Return or Enter.

Switch>

!--- The Switch> prompt is displayed.

At the switch prompt, type en to enter enable mode.
Switch>en
Switch#

IF YOU WANT YOUR OLD CONFIG BACK THEN FOLLOW STEPS 11 ONWARDS OTHERWISE YOU ARE NOW DONE!

11. Issue the rename flash:config.old flash:config.text  command at the initial dialog prompt

Type rename flash:config.old flash:config.text to rename the configuration file with its original name.
Switch#rename flash:config.old flash:config.text
Destination filename [config.text]

!--- Press Return or Enter.

Switch#
Copy the configuration file into memory.

12. Issue the copy flash:config.text system:running-config command at the initial dialog prompt

Switch#copy flash:config.text system:running-config
Destination filename [running-config]?

!--- Press Return or Enter.

1131 bytes copied in 0.760 secs
Sw1#
The configuration file is now reloaded.
Overwrite the current passwords that you do not know. Choose a strong password with at least one capital letter, one number, and one special character.
Note: Overwrite the passwords which are necessary. You need not overwrite all of the mentioned passwords.
Sw1# conf t


!--- To overwrite existing secret password

Sw1(config)#enable secret <new_secret_password>

!--- To overwrite existing vty password

Sw1(config)#line vty 0 15
Sw1(config-line)#password <new_vty_password>

Sw1(config-line)#login


!--- To overwrite existing console password

Sw1(config-line)#line con 0
Sw1(config-line)#password <new_console_password>

Write the running configuration to the configuration file with the write memory command.

Sw1#write memory
Building configuration...
[OK]
Sw1#


1 comment:

  1. Yeah glad I found this - very helpful. Restored access to a 2950 I found :-)

    ReplyDelete