Reset Cisco IOS Configuration Specific Defaults

Real World Application:

You may want to change the configuration for a specific interface, or other type of configuration resets the default Cisco IOS configuration used in the production. A great example would be you have configuration for interface FastEthernet0/0 and its about 10 rows on it and you want to clear the configuration on the interface, normally you would deny use of any command under the interface configuration before configuring all of the rows.


Quick and easy way to clear the configuration on an interface is to use the default command in global configuration, followed by the interface name and number. Configure this command to reset the interface is configured as the default "any IP address" and "off" and from there, you can apply the new configuration interface and save for a while not denying so many interfaces configuration lines.

Lab Objectives:

• Configuring interfaces FastEthernet0/0 and 10.1.1.254/24 IP address hard-coded into the full 100Mbps speed and duplex.
• Resetting the interface of the FastEthernet0/0 global configuration default command has previously been configured.

Lab Instruction:

 

Step 1. First target countries to simulate the configuration of an interface, you will need to 10.1.1.254/24 the IP address assigned to the interface FastEthernet0/0 and ass hard code speed and duplex to 100Mbps full duplex.

Router con0 is now available

Press RETURN to get started.

Router>enable

Router#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)#int fa0/0

Router(config-if)#ip add 10.1.1.254 255.255.255.0

Router(config-if)#duplex full

Router(config-if)#speed 100

Router(config-if)#no shut

%LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed

state to up

Router(config-if)#

Router(config-if)#do show run int fa0/0
Building configuration...

Current configuration : 94 bytes
!
interface FastEthernet0/0
 ip address 10.1.1.254 255.255.255.0
 duplex full
 speed 100
end

Router(config-if)#

Step 2. Interface Fa0/0 now performed by resetting to default configuration default command from the second number is the interface name and verify that the configured global configuration.
Router(config-if)#exit
Router(config)#default interface fa0/0
Building configuration...

Interface FastEthernet0/0 set to default configuration
Router(config)#

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down

%LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up

Rrouter(config)#do show run interface FastEthernet 0/0
Building configuration...

Current configuration : 73 bytes
!
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
end

Router(config)#

Configuring the Login, EXEC and MOTD Banners

Real World Application:

Be common banner Cisco devices on the network, including legal information and other unauthorized individuals trying to build an exec session with your device warning message. Try to exec session establishment, after the login banner display before the MOTD banner appears before a logon banner and user authentication. Once the individual has to start an EXEC session with the device display EXEC banners.

Lab Prerequisites:

• If you are using GNS3, than the starting R1 supported networking GNS3 topology of the stub zone.
• Establish a console session with the Router 1.

Lab Instruction:

Step 1. Target to the one you want to configure the desired login banner, inform the incoming session legal and privacy information. Configure a banner, you will need to use a delimiting character; this is one character appears only in the beginning and end of the banner. ^ Commonly used. Types of settings you can use the banner command followed by login, EXEC, the banner would prefer it to be a banner motd separator characters. As shown below, you can see the banners to configure basic logon and configuration validation through the end and reshape an exec session with the device.

Router(config)#banner login ^

Enter TEXT message.  End with the character '^'

#  This is a Login banner used to show   #

#    legal and privacy information.      #

#                                        #

#     Unauthorized users prohibited      #

^

Router(config)#end

Router#exit

As shown below is the login banner configuration verfication;

Goal 2 requires that you configure the exec banner, any authenticated exec session will show what device host name, as well as online session is established. This type of banner you want to configure, you need to know what banner marking. Banner tokens, basically you can get in a banner that calls from the device-specific information and dispatches the message to the variable set in the banner. $ (Hostname) and $ (line), shows the host name and the line number, banner tokens used in this goal.

In accordance with the requirements of objective 3 Configuring the exec banner, session establishment, use the following text to the previous line $ (line) $ (hostname)

Logon banners that you have configured the as before you execute the same command in global configuration mode, but rather the execution banner login ^ you will perform the exec^ is shown below the banner;

Router>enable

Password: 

Router#

Router#configure terminal 

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)#banner exec ^

Enter TEXT message.  End with the character '^'

Session established to $(hostname) on line $(line)

^

Router(config)#

Reset Cisco IOS Configuration Specific Defaults

You may want to change the configuration for a specific interface, or other type of configuration resets the default Cisco IOS configuration used in the production. A great example would be you have configuration for interface FastEthernet0/0 and its about 10 rows on it and you want to clear the configuration on the interface, normally you would deny use of any command under the interface configuration before configuring all of the rows.

Quick and easy way to clear the configuration on an interface is to use the default command in global configuration, followed by the interface name and number. Configure this command to reset the interface is configured as the default "any IP address" and "off" and from there, you can apply the new configuration interface and save for a while not denying so many interfaces to configure the thread.

Lab Prerequisites:

• If you are using GNS3 than load the Stub Area Networking GNS3 topology and start R1.
• Establish a Console session with Router 1.

Lab Objectives:

Configuring interfaces FastEthernet0/0 and 10.1.1.254/24 IP address hard-coded into the full 100Mbps speed and duplex.

Reset interface on the FastEthernet0/0 using the default global configuration command configured earlier.

Lab Instruction:

Step 1. First target countries to simulate the configuration of an interface, you will need to 10.1.1.254/24 the IP address assigned to the interface FastEthernet0/0 and ass hard code speed and duplex to 100Mbps full duplex.

Router con0 is now available

Press RETURN to get started.

Router>enable

Router#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)#int fa0/0

Router(config-if)#ip add 10.1.1.254 255.255.255.0

Router(config-if)#duplex full

Router(config-if)#speed 100

Router(config-if)#no shut

%LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed

state to up

Router(config-if)#

Router(config-if)#do show run int fa0/0

Building configuration...

Current configuration : 94 bytes

!

interface FastEthernet0/0

 ip address 10.1.1.254 255.255.255.0

 duplex full

 speed 100

end

Router(config-if)#

Step 2. Now Fa0/0 resets to the default configuration of the interface default command is executed from a number followed by the interface name and verify that the configured global configuration.

Router(config-if)#exit

Router(config)#default interface fa0/0

Building configuration...

Interface FastEthernet0/0 set to default configuration

Router(config)#

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to down

%LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up

%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up

Rrouter(config)#do show run interface FastEthernet 0/0

Building configuration...

Current configuration : 73 bytes

!

interface FastEthernet0/0

 no ip address

 duplex auto

 speed auto

end

Router(config)#

Recovering IOS on a Catalyst Switch

Recovery on a Cisco switch Cisco IOS image that is very nice to know, don't need it and need it, do not know one of its tasks. In the field, you may find yourself faced with a Cisco switch doesn't start or crashes, when you start the IOS image due to possible damage.

Lab Prerequisites:

• The lab will require genuine exchanger, because you can't use GNS3 emulation of the lab.
• Cisco IOS on switches must perform this lab is damaged or missing, to simulate this error can erase Flash to practice this lab.
• Equipment the active console session is required.
• You will need to use HyperTerminal/SecureCRT PuTTY does not support xModem.

Lab Objectives:

• Boot the exchanger to exchanger ROM mode.
• Initialize the Flash file system.
• Optional-if you want Flash file system formats. (This will remove your boot configuration)
• Is set to 115,200 baud rate increase the Xmodem transfer speed and reduce the time required to recover the IOS image.
• Via xModem copy the Cisco IOS image to Flash memory:
• To set the new image name located Flash startup parameters:
• Cancel set the baud rate, it will default to 9,600 back.
• Start switch, and verify that the switch boots.

Lab Instruction:

Restore a previous hotfix to configure Cisco Catalyst series switch Cisco IOS image is quite a big difference and a lot of "old school" way IOS image restoration. Unfortunately, fixed-configuration switches need to use xModem restore corrupt or missing IOS images with Cisco and Cisco 4,500 6,500 series supervisor engine, uses Compact Flash cards of different

Step 1. Start your exchanger to exchanger ROM mode. This usually involves holding down a STAT button when you plug in the power supply before the switch. You can click here to check out the program you need!

As soon as you boot your exchanger to exchanger ROM mode you will see the following schedule;

Boot Sector Filesystem (bs) installed, fsid: 2

Base ethernet MAC Address: 00:14:f2:d2:41:80

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:

    flash_init

    boot

Step 2. Once you have the boot ROM to switch modes, you need to initialize the Flash file system by executing the flash_init command, as shown below;

switch: flash_init

Initializing Flash...

flashfs[0]: 1 files, 1 directories

flashfs[0]: 0 orphaned files, 0 orphaned directories

flashfs[0]: Total bytes: 15998976

flashfs[0]: Bytes used: 12474880

flashfs[0]: Bytes available: 3524096

flashfs[0]: flashfs fsck took 10 seconds.

...done Initializing Flash.

Step 3. optional if your image is damaged you can format your Flash file system by performing a format Flash: command, but this will remove your boot configuration looks like this!!!

Switch: format flash:

Are you sure you want to format "flash:" (all data will be lost) (y/n)?y

flashfs[0]: 0 files, 1 directories

flashfs[0]: 0 orphaned files, 0 orphaned directories

flashfs[0]: Total bytes: 7741440

flashfs[0]: Bytes used: 1024

flashfs[0]: Bytes available: 7740416

flashfs[0]: flashfs fsck took 12 seconds.

Filesystem "flash:" formatted

Step 4. To speed up the xModem file transfer rate you need by doing sets the baud rate of 115,200 console line baud rate is set to 115,200. If you do this you will need to disconnect the console session with the serial line speed from 9,600 to 115,200. But if you do not set the baud rate is 115,200 your file transfer can be up to 3 hours

switch: set BAUD 115200.

Step 5. Once the baud rate setting and reconnect to your Cisco switch console, you are ready to copy the IOS image via xModem to the switch's Flash memory, through the implementation of xModem file transfer that copy the Xmodem:Flash:filename.bin and start from the terminal emulation software to the client looks like this;

switch: copy xmodem: flash:c3560-ipservicesk9-mz.122-53.SE.bin

Begin the Xmodem or Xmodem-1K transfer now...

CCC

Starting xmodem transfer.  Press Ctrl+C to cancel.

Transferring c3560-ipservicesk9-mz.122-53.SE.bin...

  100%   12181 KB    6 KB/s 00:31:56       0 Errors

.................................................................

.................................................................

.................................................................

File "xmodem:" successfully copied to "flash:c3560-ipservicesk9-mz.122-53.SE.bin"

switch:

Recovering IOS on a 2600 Series

Real World Application:

Cisco 2,600 series multi-service router platform is a dying bread because Cisco 2,800 series has taken its place, however the 2600 series router that is still the choice when it comes to building your own Cisco lab. Cisco is very similar to 2,600 people more vulnerable to the latest generation of routers, so the lab would be a valuable lesson.

Lab Prerequisites:

• You need a Cisco series routers or 2,600 more in all the Cisco IOS image is corrupt or no IOS image. If you want to simulate the lab can wipe your device and restart Flash. Please note that you need to clear it before backing up the Cisco IOS image, unless you have another image you want on hand can be loaded onto the device.
• Console connection to the device is required
• You need to install on your PC to restore the image on the TFTP server.

Lab Objectives:

• Guide on the Cisco router to ROM mode by breaking the boot sequence use keys CTRL + pause break
• Including the IP address, subnet mask, default gateway, TFTP server, TFTP image name TFTPDNLD variable settings required to perform this procedure.
• Implement TFTPDNLD command and loads the image into RAM by using the-r switch.
• Startup to Cisco IOS, configure your router so that you can copy the Cisco IOS image from the TFTP server to Flash memory.
• Once you have completed all the necessary configuration copy the IOS image from the TFTP server to the Flash memory.
• After replication has completed, restart the router and verify successful boot image.

Lab Instruction:

Note to complete this lab, you need a real Cisco 2,600 series or greater, the lab cannot emulate GNS3 applications.

Step 1. Assume you already have a active console session to the router and power on the device you should automatically put people more easily if you have a Cisco IOS image is corrupt or missing. However you have "press ENTER to start" boot prompt, then you have to the IOS image, you should open a power cycle, the router, and press CTRL + break to break the boot sequence, and is placed in ROM monitor mode, as shown below;

System Bootstrap, Version 12.2(8r) [cmong 8r], RELEASE SOFTWARE (fc1)

Copyright (c) 2003 by cisco Systems, Inc.

C2600 platform with 262144 Kbytes of main memory

device does not contain a valid magic number

boot: cannot open "flash:"

boot: cannot determine first file name on device "flash:"

rommon 1 >

By performing you can see all available talent is easier to command as follows to 2651XM; help command

Step 2. In this laboratory, we are most interested in the tftpdnld command.

This command will copy the IOS image from the TFTP server to Flash or load it directly to the RAM. By performing the tftpdnld, you can see all the commands for variables that you want to work;

rommon 2 > tftpdnld

Missing or illegal ip address for variable IP_ADDRESS

Illegal IP address.

usage: tftpdnld [-r]

  Use this command for disaster recovery only to recover an image via TFTP.

  Monitor variables are used to set up parameters for the transfer.

  (Syntax: "VARIABLE_NAME=value" and use "set" to show current variables.)

  "ctrl-c" or "break" stops the transfer before flash erase begins.

  The following variables are REQUIRED to be set for tftpdnld:

            IP_ADDRESS: The IP address for this unit

        IP_SUBNET_MASK: The subnet mask for this unit

       DEFAULT_GATEWAY: The default gateway for this unit

           TFTP_SERVER: The IP address of the server to fetch from

             TFTP_FILE: The filename to fetch

  The following variables are OPTIONAL:

          TFTP_VERBOSE: Print setting. 0=quiet, 1=progress(default), 2=verbose

      TFTP_RETRY_COUNT: Retry count for ARP and TFTP (default=12)

          TFTP_TIMEOUT: Overall timeout of operation in seconds (default=7200)

         TFTP_CHECKSUM: Perform checksum test on image, 0=no, 1=yes (default=1)

         FE_SPEED_MODE: 0=10/hdx, 1=10/fdx, 2=100/hdx, 3=100/fdx, 4=Auto(deflt)

  Command line options:

   -r: do not write flash, load to DRAM only and launch image

rommon 3 >

Depending on the target, we will need to set the variables you want to implement the tftpdnld command. You can issue the command to view the current setting of set variables.

Shown below is the required variables to execute tftpdnld successfully.

rommon 4 > IP_ADDRESS=10.1.1.10

rommon 5 > IP_SUBNET_MASK=255.255.255.0

rommon 6 > DEFAULT_GATEWAY=10.1.1.254

rommon 7 > TFTP_SERVER=172.16.20.17

rommon 8 > TFTP_FILE=c2600-i-mz.123-26.bin

You do not need a default gateway if the TFTP server is your Cisco routers on the same subnet.

Once you've set you can continue learning objective 3 by executing the tftpdnld command variable you want to copy with the-r switch Cisco IOS image from the TFTP server, load it directly into memory.

ommon 9 > tftpdnld -r

          IP_ADDRESS: 10.1.1.10

      IP_SUBNET_MASK: 255.255.255.0

     DEFAULT_GATEWAY: 10.1.1.254

         TFTP_SERVER: 172.16.20.17

           TFTP_FILE: c2600-i-mz.123-26.bin

.....

Receiving c2600-i-mz.123-26.bin from 172.16.20.17 !!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

File reception completed.

program load complete, entry point: 0x80008000, size: 0x765238

Self decompressing the image : ############################################## [OK]

Smart Init is enabled

smart init is sizing iomem

  ID            MEMORY_REQ                 TYPE

00036F          0X00103980 C2651XM Dual Fast Ethernet

000065          0X00031500 Four port Voice PM

                0X00098670 public buffer pools

                0X00211000 public particle pools

TOTAL:          0X003DE4F0

If any of the above Memory Requirements are 

"UNKNOWN", you may be using an unsupported

configuration or there is a software problem and

system operation may be compromised.

Rounded IOMEM up to: 4Mb.

Using 3 percent iomem. [4Mb/128Mb]

              Restricted Rights Legend

Use, duplication, or disclosure by the Government is

subject to restrictions as set forth in subparagraph

(c) of the Commercial Computer Software - Restricted

Rights clause at FAR sec. 52.227-19 and subparagraph

(c) (1) (ii) of the Rights in Technical Data and Computer

Software clause at DFARS sec. 252.227-7013.

           cisco Systems, Inc.

           170 West Tasman Drive

           San Jose, California 95134-1706

Cisco Internetwork Operating System Software 

IOS (tm) C2600 Software (C2600-I-M), Version 12.3(26), RELEASE SOFTWARE (fc2)

Technical Support: http://www.cisco.com/techsupport

Copyright (c) 1986-2008 by cisco Systems, Inc.

Compiled Mon 17-Mar-08 15:23 by dchih

cisco 2651XM (MPC860P) processor (revision 0x200) with 126976K/4096K bytes of memory.

Processor board ID JAE08030QZL (457188033)

M860 processor: part number 5, mask 2

Bridging software.

X.25 software, Version 3.0.0.

2 FastEthernet/IEEE 802.3 interface(s)

2 Serial network interface(s)

32K bytes of non-volatile configuration memory.

49152K bytes of processor board System flash (Read/Write)

         --- System Configuration Dialog ---

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

Recovering IOS on a 2500 Series

Real World Application:

Although Cisco networking 2,500 series have a long life's grand plan, but they are usually used in a lab environment. However, there were a few times and still today 8+-year production run of luck. Drive maker could plead guilty to upgrade many tasks will be more conducive to networking business sees it as $$$. Why upgrade work is fully functional and has been 8+ years of device? All corrupt IOS or no image on 2500 series routers are usually used for this process. It is common to buy router Flash memory erasure, in which case you will need to perform an image restoration process.

Lab Prerequisites:

• You need a corrupted image or not the Cisco IOS image in all 2,500 series routers. If you want to simulate the lab can wipe your device and restart Flash. Please note that you need to clear it before backing up the Cisco IOS image, unless you have another image you want on hand can be loaded onto the device.
• A console connection to the device is required.
• You need to install on your PC to restore the image on the TFTP server.

Lab Objectives:

• By breaking the boot sequence use keys CTRL + pause break boot into ROM models of Cisco routers
• Change the configuration register boot ROM (BOOT) images. The configuration register is to use 0x2141
• By issuing I initialize a router command
• For Ethernet interfaces assigned IP address and configure a default gateway (if required)
• Copy the Cisco IOS image from the TFTP server to the Flash memory.
• Change the configuration register back to its default value, and heavy equipment to ensure that the IOS image on the device to normal startup and recovery.

Lab Instruction:

Step 1. By breaking the boot sequence boot the router to ROM mode the keystrokes CTRL + pause break

Copyright (c) 1986-1996 by cisco Systems

2500 processor with 14336 Kbytes of main memory

Abort at 0x10CFA0A (PC)

>

Step 2. Change the configuration register boot ROM (BOOT) images. Configuration registers are used by 0x2141

>o/r 0x2141

Step 3. Initialize the router by issuing the  i  command

>i

System Bootstrap, Version 11.0(10c), SOFTWARE

Copyright (c) 1986-1996 by cisco Systems

2500 processor with 14336 Kbytes of main memory

[OUTPUT TRUNCATED]

Press RETURN to get started!

Step 4. assign an IP address to the Ethernet interface, and configure a default gateway (if required).

Press RETURN to get started!

Router(boot)>enable

Router(boot)#config t

Router(boot)(config)#interface e0

Router(boot)(config-if)#ip add 10.1.1.20 255.255.255.0

Router(boot)(config-if)#no shut

Router(boot)(config-if)#exit

****NOTE: The line below is optional if your TFTP server is not on the same network****

Router(boot)(config)#ip default-gateway 10.1.1.254

Router(boot)(config)#end

Upgrading the Cisco IOS

Real World Application:

Common tasks between Cisco engineers as the new IOS image is usually released within 3 months, or upgrade the Cisco IOS device. New version includes bug fixes and new features into devices that are available. Upgrade the Cisco IOS on a router or switch is a Cisco network engineer has to know.

Lab Prerequisites:

• Loose-leaf book free CCNA guides R1 GNS3 lab topology.
• An active console sessions to R1
• A new Cisco IOS image is compatible with your Cisco device.
• TFTP server needs of the lab. You may need to download Solarwinds TFTP server and configure it again and try the lab.

Lab Objectives:

• If needed, download and install Solarwinds TFTP server.
• In the root directory of the TFTP server where the new Cisco IOS image file.
• Configure the TFTP server and Cisco devices can be in the same IP subnet, IE;10.1.1.1/24 10.1.1.2/24&
• Make sure that you have an Ethernet connection to your Cisco TFTP server that you are upgrading.
• New image file from the TFTP server to your Cisco device, you are prompted to erase the Flash memory.
• Once you copy the new Cisco IOS image in Flash memory devices, restart the device and verify that the upgrade was successful.

Lab Instruction:

Please note that the lab needs real Cisco routers or switches perform GNS3 is not loaded from the Flash image. You can perform this procedure on GNS3, but you will not be able to restart the device, and verify a successful upgrade.

As the latest IOS image release, at least once every three months to fix the bug and providing new features and enable a new device hardware upgrade Cisco Internetwork operating system on the device (IOS) is a very common practice.

First off you need to install and use the patch cable to the router, run from your PC or regular patch cable from the personal computer to the exchanger is running run the TFTP server on your PC.

To complete this lab's third goal will require the console session to a Cisco router or switch. Make sure that you want to specify the IP address of the Cisco devices is in the same subnet as the PC. In this lab, we'll use Cisco equipment PC 10.1.1.1/24 and 10.1.1.2/24. Goals require that you connect to your PC's Ethernet IP addresses that are configured on the interface. As shown in the following example, interface connected directly to the PC FastEthernet0/0;

Router con0 is now available

Press RETURN to get started.

Router>enable

Password: 

Router#configure terminal

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)#interface fastethernet 0/0

Router(config-if)#ip address 10.1.1.2 255.255.255.0

Router(config-if)#no shutdown

Router(config-if)#end

Router#

To ensure that you have the Cisco between the device and your computer can execute the ping command, the Ethernet connection as shown below.

Once you've verified that you then you are ready to copy the new image into Flash memory devices to your PC an IP connection. You achieve this goal by implementation of the copy TFTP Flash command in privileged mode. After you execute this command you will be prompted for the IP address of the TFTP server and you want to copy from the TFTP server to the Flash memory in the name of the image file.

Router#copy tftp flash

Address or name of remote host []? 10.1.1.1

Source filename []? c2600-adventerprisek9-mz.124-15.T11.bin

Destination filename [c2600-adventerprisek9-mz.124-15.T11.bin]?

Accessing tftp://10.1.1.1/c2600-adventerprisek9-mz.124-15.T11.bin...

Erase flash: before copying? [confirm]

Erasing the flash filesystem will remove all files! Continue? [confirm]

Erasing device... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee ...erased

Erase of flash: complete

Loading c2600-adventerprisek9-mz.124-15.T11.bin from 10.1.1.1 (via FastEthernet0/0): 

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[OK - 34634180 bytes]

Verifying checksum... CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC OK (0x8E89)

34634180 bytes copied in 486.894 secs (71133 bytes/sec)

Router#

Recovering IOS on a 2500 Series

Real World Application:

Although Cisco networking 2,500 series have a long life's grand plan, but they are usually used in a lab environment. However, there were a few times and still today 8+-year production run of luck. Drive maker could plead guilty to upgrade many tasks will be more conducive to networking business sees it as $$$. Why upgrade worked perfectly normal and 8+ years of equipment? All corrupt IOS or no image on 2500 series routers are usually used for this process. It is common to buy router Flash memory erasure, in which case you will need to perform an image restoration process.

Lab Prerequisites:

You need a corrupted image or not the Cisco IOS image in all 2,500 series routers. If you want to simulate the lab can wipe your device and restart Flash. Please note that you need to back up before the Cisco IOS image to remove it, unless you have another image you want on hand can be loaded into the device.
A console connection to the device is required.

You need to install on your PC to restore the image on the TFTP server.

Lab Objectives:

By breaking the keystrokes CTRL + pause break of the Cisco router boot sequence to boot to ROM mode
Change the configuration register boot ROM (BOOT) images. Configuration registers are used by 0x2141
I initialize a router commands issued through
For Ethernet interfaces assigned IP address and configure a default gateway (if required)
Copy the Cisco IOS image from the TFTP server to the Flash memory.

Change the configuration register back to its default value, and reloading the device to make sure the IOS image boots on the device and restore.

Lab Instruction:

Step 1. Boot the router into ROM mode by breaking the boot sequence using the keystroke CTRL+PAUSE BREAK

Copyright (c) 1986-1996 by cisco Systems
2500 processor with 14336 Kbytes of main memory

Abort at 0x10CFA0A (PC)
>

Step 2. Change the configuration register to boot the ROM(BOOT) image. Configuration register to be used is 0×2141

>o/r 0x2141

Step 3. I initialize a router commands issued through

>i
System Bootstrap, Version 11.0(10c), SOFTWARE
Copyright (c) 1986-1996 by cisco Systems
2500 processor with 14336 Kbytes of main memory

[OUTPUT TRUNCATED]

Press RETURN to get started!

Step 4. assign an IP address to the Ethernet interface, and configure a default gateway (if required).

Press RETURN to get started!

Router(boot)>enable
Router(boot)#config t
Router(boot)(config)#interface e0
Router(boot)(config-if)#ip add 10.1.1.20 255.255.255.0
Router(boot)(config-if)#no shut
Router(boot)(config-if)#exit
****NOTE: The line below is optional if your TFTP server is not on the same network****
Router(boot)(config)#ip default-gateway 10.1.1.254
Router(boot)(config)#end

Step 5. Copy the Cisco IOS image from the TFTP server into flash memory.

Router(boot)#copy tftp flash

System flash directory:
No files in System flash
[0 bytes used, 8388608 available, 8388608 total]
Address or name of remote host [255.255.255.255]? 172.16.20.17
Source file name? c2500-i-l.121-27b.bin
Destination file name [c2500-i-l.121-27b.bin]?
Accessing file 'c2500-i-l.121-27b.bin' on 10.1.1.1...
Loading c2500-i-l.121-27b.bin from 172.16.20.17 (via Ethernet0): ! [OK]

Erase flash device before writing? [confirm]

Copy 'c2500-i-l.121-27b.bin' from server
  as 'c2500-i-l.121-27b.bin' into Flash WITH erase? [yes/no]y
Erasing device... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee ...erased
Loading c2500-i-l.121-27b.bin from 172.16.20.17 (via Ethernet0): !!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!! [OUTPUT TRUNCATED] !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 8040260/8388608 bytes]

Verifying checksum...  OK (0xCB96)
Flash copy took 0:03:58 [hh:mm:ss]
Router(boot)#

Step 6. Change the configuration register back to its default value, and reloading the device to make sure the IOS image boots on the device and restore.

Router(boot)#configure terminal
Router(boot)(config)#configuration-register 0x2102
Router(boot)(config)#end
Router(boot)#reload

System configuration has been modified. Save? [yes/no]: n
Proceed with reload? [confirm]

00:06:51: %SYS-5-RELOAD: Reload requested

System Bootstrap, Version 11.0(10c), SOFTWARE
Copyright (c) 1986-1996 by cisco Systems
2500 processor with 14336 Kbytes of main memory

Notice: NVRAM invalid, possibly due to write erase.

F3: 7916604+123624+619980 at 0x3000060

              Restricted Rights Legend

Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software - Restricted
Rights clause at FAR sec. 52.227-19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227-7013.

           cisco Systems, Inc.
           170 West Tasman Drive
           San Jose, California 95134-1706

Configuring a Loopback Interface

Real World Application:

Loopback interface management of common application scenarios, including tunnel interface, the source/destination, network simulation, dynamic routing processes the router ID link, and others. CCNA as you would need in order to be able to create and delete the loopback interfaces from Cisco devices.


This lab will teach you how to configure the loopback interface.

Lab Prerequisites:

If you use GNS3 started free CCNA R1 load Binder GNS3 topology.

Establish a console session of Router 1.

Lab Instruction:

A loopback interface is a software-based "always up" logical interfaces. They will not be bound without any physical interface so they can go unless they are administratively closed.


To create you need to navigate the global configuration mode command interface loop interface loopback interface # creates automatically. Configuration looks like this;

Router con0 is now available

Press RETURN to get started.

Router>enable
Password:
Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#interface loopback ?
    Loopback interface number

Router(config)#interface loopback 1
%LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback1, changed state to up
Router(config-if)#

After creating the interface you will see interface changes, open immediately. According to the requirements the goal you see below; on the interface to configure the IP address 10.233.21.251/24

Router(config-if)#ip address 10.233.21.251 255.255.255.0

Loopback 1 target 2 ask us to remove the interface, you can negate the interface command does not use any interface loopback # command, as shown below; remove the loopback interface

Router(config-if)#no interface loopback 1
% Not all config may be removed and may reappear after reactivating the logical-interface/sub-interfaces
Router(config)#
%LINK-5-CHANGED: Interface Loopback1, changed state to administratively down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback1, changed state to down

Once you have deleted the interface you will find that not all configuration may have been deleted, and restart the logical interface/sub-interface may reappear after a warning.

Cisco IOS problem this neighborhood for many years, it has not been fixed. Basically this warning lets you know that if you delete the logical no interface or sub-interface command some of the previous configuration may return to re-create the same interface. If you encounter this problem, router overload will resolve this problem.

Interface IP Address Configuration

Real World Application:

As a Cisco network engineer, you need to know how to configure IP address on different types of interfaces. After all, what good is a Cisco router, if it cannot be routed?

Cisco equipment, network equipment, the IP address assigned to an interface is the basic requirement for all Cisco devices.


However, you can have more than one IPv4 address assigned to a single interface, but there's a problem here. When working with dynamic routing protocols, ads from the primary address. Secondary addresses commonly used IP address migration, moving from class c to class a addresses during the programme.

Lab Objectives:

• IConfigure 10.234.51.254/24 FastEthernet0/0 the primary IP address on the interface
• Configuration 172.27.48.254/24 a secondary IP address on the interface FastEthernet0/0
• FastEthernet0/0 interface is activated.
• Verify the configuration by running the configuration changes.

Lab Instruction:

The IP address configured on the Cisco routers and switches is a very common task, you need to know how to do that, and does not refer to any document as a CCNA.


To get started, browse your way into the global configuration mode is shown below;

Router con0 is now available

Press RETURN to get started.

Router>enable
Password: 
Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#

Step 1. Configure IP address 10.234.51.254 on the--FastEthernet0/0 interface. In order for this configuration you need to place themselves in the FastEthernet0/0 interface configuration mode looks like this;

To view the interface configuration is available for the implementation of the interface? From global configuration mode.


Router(config)#interface FastEthernet 0/0
Router(config-if)#

In interface configuration mode, use the command syntax is IP address n.n.n.h s.s.s.m; completed the first lab targets we need to perform IP address 10.234.51.254 255.255.255.0 FastEthernet0/0 see below; interface configuration mode

Router(config-if)#ip address 10.234.51.254 255.255.255.0
Router(config-if)#

Step 2. Interface FastEthernet0/0 configuration 172.27.48.254/24 a secondary IP address

As indicated by laboratory, the secondary IP addresses typically used during network re IP migration. By Cisco systems, architectural design of the secondary IP addresses is not recommended as production. The second goal to complete this lab, you need the IP address command to use the correct address and simply add a secondary to the command syntax for the end of the word.

Router(config-if)#ip address 172.27.48.254 255.255.255.0 secondary
Router(config-if)#

Step 3. Activate the FastEthernet0/0 Interface. By default, all interfaces on a Cisco router are placed in “Administratively Down”. To bring an interface up, issue the no shutdown command.

Router(config-if)#no shutdown
Router(config-if)#
%LINK-3-UPDOWN: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
Router(config-if)#

Navigating the Cisco Command Line Interface

Real World Application:

As Cisco network engineer, you need to the main navigation, through the command line interface as all Cisco via the CLI to configure the device. However, there are several JAVA GUI configuration, such as airbags and PDM, frequently frowning, GUI configuration tool that enables device configuration to a give agents with the CLI and unclean. CCNA various CLI modes you include, but are not limited to, global configuration mode, user mode and privileged mode interface configuration mode, the router configuration mode, the VLAN database configuration mode and line mode, access list configuration mode the main navigation to the desired configuration mode.

Lab Objectives:

• Familiarize yourself with the different ways based on Cisco IOS devices.
• Familiar with legacy terminal keystroke combination for CLI navigation.

Lab Instruction;

Master navigation through the Cisco command line interface is the sine qua non for any Cisco engineers. There are several different types of Cisco CLI mode. User-mode the first time you put pressure returned after entering your user authentication information, or vty line password mode. Once you're into user mode, you are limited, you can be performed from CLI commands.

However, many command at the user level can be very rich in content, which include, but are not limited to; ping, traceroute, show CDP neighbor display version and show interfaces command.

In privileged mode, you want to give the ability to configure the device and perform administrative commands, including, but not limited to; configuring, clear, heavy, more, copy, delete, clear, and debugging.


In the terminal box as shown below, you can see after pressing enter, you have to put Cisco CLI ">" next to the larger and then log in to the host name. This is known as user mode.

Router con0 is now available

Press RETURN to get started.

Router>

At any point in Cisco CLI, you can use the question mark for the context mode sensitive notes lists commands available to perform from your current permission levels. As shown below;

Router>?
Exec commands:
  access-enable    Create a temporary Access-List entry
  access-profile   Apply user-profile to interface
  clear            Reset functions
  connect          Open a terminal connection
  crypto           Encryption related commands.
  disable          Turn off privileged commands
  disconnect       Disconnect an existing network connection
  emm              Run a configured Menu System
  enable           Turn on privileged commands
  ethernet         Ethernet parameters
  exit             Exit from the EXEC
  help             Description of the interactive help system
  lat              Open a lat connection
  lock             Lock the terminal
  login            Log in as a particular user
  logout           Exit from the EXEC
  mrinfo           Request neighbor and version information from a multicast router
  mstat            Show statistics after multiple multicast traceroutes
  mtrace           Trace reverse multicast path from destination to source
  name-connection  Name an existing network connection
 --More--

You can use line-by-line to display or the space bar to display the available commands the next paragraph. If you want to exit the list, without pressing the SPACEBAR continues to reach the end of the list, press the Q key.

Time in user mode you can elevate your permissions from user-mode CLI by issuing the command to enable the prompt. If you enable password or enable secret configuration, and then you will be prompted to provide this type of authentication information, elevate their own privileges.

Please note that when you enter a password on a Cisco device, you will not see the password you typed. This is intentional by Cisco to prevent people from watching you on the shoulder.

Router>enable
Password:
Router#

When you are in privileged mode, you can configure your router by entering the command configure Terminal. This command you enter global configuration mode you can make configuration changes to device. Please note that this is not always possible, if command authorization, Cisco access control server before you execute each command authorized Cisco ACS server prior to execution. ACS server (this is outside the scope of the CCNA certification) allow security agents to control which users can perform what commands based on configured policy.

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#

(By the (config) # prompt) in global configuration mode, you have access to different configuration mode interface configuration mode or router configuration mode, the VLAN database configuration mode, access-list configuration mode, and many others;


Router(config)#interface f0/0
Router(config-if)#router eigrp 1
Router(config-router)#ip access-list extended example_acl_name
Router(config-ext-nacl)#line con 0
Router(config-line)#

Cisco Device Initial Configuration Dialog

Real World Application:

Are usually engineers worry about the initial configuration dialog, but boring you need to know it for the CCNA exam. But once you get this dialog box to configure Cisco IOS as a navigation experience, do not use this configuration dialog box, you will know how to manually set up.


However; shipping abroad, have is actually pretty useful when configuring devices in the initial configuration dialog, you need to experience personal to configure the basic connection to the device. Other then this case, the initial configuration dialog box is usually ignored all experienced network engineers; however, as CCNA requires a familiarity with the initial configuration dialog box.

Lab Prerequisites:

If You’re using GNS3 than load the Stub Area Networking GNS3 topology and start R1 than establish a console session with R1.

Lab Instruction:

When you open a new Cisco box, instead it is a Cisco switch or router, and at the boot prompt after the device is determined by the initial configuration dialog box. You will also be prompted by this dialog box if the write erase command in privileged mode and load, it will clear the NVRAM and set no startup configuration in NVRAM, the device prompts you, but do not start the initial configuration dialog box.


As shown below in the configuration box you will see the initial configuration dialog box prompts; choose and press ENTER.

       --- System Configuration Dialog ---

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

After you start the system configuration dialog box, step by step procedure is relatively easy, explains the details of the options in the dialog box. This lab will only demonstrate basic management configuration, however it is up to you to traverse the entire system configuration dialog box does not prompt, type II is shown below;

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 '[]'.

Basic management setup configures only enough connectivity
for management of the system, extended setup will ask you
to configure each interface on the system

Would you like to enter basic management setup? [yes/no]: yes

After typing yes at the basic management setup prompt you’ll be given the options to configure the hostname and passwords as shown below;

After basic management dialog box, set the password, the system will prompt you to enable SNMP (simple network management protocol) is an industry standard protocol that allows through the device management API. When you said I you will be asked to configure SNMP community string, as shown below;

Configure SNMP Network Management? [no]: yes
    Community string [public]: COMMUNITYSTRINGGOESHERE

Configuration, you will be asked to configure a single interface to manage the network, SNMP option to keep mind you'll need to type out the entire name of the interface, as shown below;

Current interface summary

Any interface listed with OK? value "NO" does not have a valid configuration

Interface                  IP-Address      OK? Method Status       Protocol
Interface                  IP-Address      OK? Method Status       Protocol
FastEthernet0/0            unassigned      NO  unset  up           up    
FastEthernet0/1            unassigned      NO  unset  up           up    
Serial1/0                  unassigned      NO  unset  up           down  
Serial1/1                  unassigned      NO  unset  up           down  
Serial1/2                  unassigned      NO  unset  up           down  
Serial1/3                  unassigned      NO  unset  up           down      

Enter interface name used to connect to the
management network from the above interface summary: FastEthernet0/0

Once you’ve selected an interface that will participate in the management network, you’re required to configure the IP parameters for that interface as shown below;

Configuring interface FastEthernet0/0:
  Operate in full-duplex mode? [no]: 
  Configure IP on this interface? [yes]: 
    IP address for this interface: 10.1.1.2
    Subnet mask for this interface [255.0.0.0] : 255.255.255.0
    Class A network is 10.0.0.0, 24 subnet bits; mask is /24

Cisco Catalyst Switch Password Reset

Real World Application:

Status of all people forgotten password forgotten password of the day but on the Cisco Catalyst series switches can be frustrating. With various Cisco router, you must switch on the Control Panel, but I think it will be a remote desktop control panel cable to the computer connected to a switch or physical proximity switches. However Frustrating part is a switch in order to switch boot into ROM, you need to switch on the body to pull it off and the front mode button press and hold the power plug it back.

This laboratory will discuss the reset and (or) clears the password for Cisco Catalyst LAN switches include, but are not limited to 2900XL 2950,3500XL, 3,550, 3,560 series switches.


For this reason forgot to switch password can be quite frustrating. As a CCNA certified network engineer, you need to know how to perform this procedure, and does not refer to any Cisco documentation.

Lab Objectives:

• By pressing and holding the mode button and switch the power switch inserted into ROM boot switch.
• Rename configuration in the Flash file to a different name, such as; config.old.
• Does the start switch and the Flash:config.old content to running configuration after you receive the privileged level of access.
• Runs the specified configure boot configuration will be updated through synchronization to copy the configuration to NVRAM.

Lab Instruction:

Step 1 . Start the exchanger to exchanger ROM by pressing and holding the mode button, in front of the switch and insert the power switch on the left side. Please note that different Exchange requires you to hold different amount of time mode button.

As shown in the following table indicate that you need to hold down the mode button, turn on the power switch; time after insertion.

Step 2 . Once you have successfully guided to switch ROM, you will see the following scheduling;

Boot Sector Filesystem (bs) installed, fsid: 2

Base ethernet MAC Address: 00:14:f2:d2:41:80

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:

flash_init

boot

switch:

Step 3. Once your at the SWITCH ROM prompt you’ll need to initialize the flash by typing the flash_init command.

switch:flash_init

Initializing Flash...

flashfs[0]: 5 files, 1 directories

flashfs[0]: 0 orphaned files, 0 orphaned directories

flashfs[0]: Total bytes: 15998976

flashfs[0]: Bytes used: 12282368

flashfs[0]: Bytes available: 3716608

flashfs[0]: flashfs fsck took 10 seconds.

...done Initializing Flash.

switch:

Step 4. List the files stored in flash to view the avaliable configuration text files. By default the configuration file name is config.text;

switch:dir flash:

Directory of flash:/

    1  -rwx  10573494                 c3560-advipservicesk9-mz.122-44.SE6.bin

    2  -rwx  684                      vlan.dat

    3  -rwx  1938                     private-config.text

    4  -rwx  1654                     config.text

    5  -rwx  3096                     multiple-fs

3716608 bytes available (10508886 bytes used)

switch:

Step 5. You will see in the given config.text is 1654 bytes in the above example, this file renamed to config.old

If you just want to erase instead of reset password configuration you can use to remove the Flash:config.text command.

switch:rename flash:config.text flash:config.old

Step 6. Is config.text named config.old verifies that the document actually was renamed the correct dir Flash: command. Once you verify that the configuration file has been renamed from the boot command switch.

Step 7. Once the switch has started initial configuration settings for your system will prompt, ignore this user mode access.

        --- System Configuration Dialog ---

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

Switch>

Step 8. If you don't want to reset the password in the description referred to in the 5th step, you can stop now. If you want to reset the password on the configured before proceed to step 9.

Step 9. Change to privileged mode and copy the contents of the old start-up configuration to the running config using the command copy flash:config.old run

Switch>enable

Switch#copy flash:config.old run

Destination filename [running-config]?

1654 bytes copied in 9.647 secs (171 bytes/sec)

ARSCORESW1#

Step 10. After you've loaded the old configuration file as a configuration of the round, you are in privileged mode, you will be able to change your password, enable secret password or line. Once you have changed the password for start command can be run by issuing copies to save the configuration.

Switch#configure terminal

Switch(config)#enable password NEWENABLEPASSWORD

Switch(config)#line con0

Switch(config-line)#password NEWCONSOLELINEPASSWORD

Switch(config-line)#end

Switch#copy run start

Destination filename [startup-config]? 

Building configuration...

[OK]

0 bytes copied in 1.309 secs (0 bytes/sec)

Switch#

How to Cisco 2600 Series Password Reset

Real World Application:

Cisco 2600 series routers in a lab environment using the most popular routers and many still exist today, many businesses have Moto "if it works don't fix it"


Password recovery or sterilization contrary to the contents of NVRAM on Cisco router 2600 series or it is the next generation of router is a very common procedure, should be aware of any CCNA no document links.

Lab Prerequisites:

Cisco 2600 series routers, or larger, with unknown control or enable password.

You cannot log on to the device to the activities of the serial console sessions

Lab Objectives:

Cisco 2,600 series routers, himself, under the ROM monitor mode when the power is turned breaking the boot sequence.
When content is changed to 0x2142 NVRAM in bypass startup and reset the router, the router configuration registers
(Option 1)-a guide, yourself in privileged mode and copy the start up configuration to the running configuration. After that, you may change the password or the password is enabled and configured to write to NVRAM, through the copy run start command issued.
(Option 2) – a guide to turn themselves into privileged mode, a write wipe clear the contents of the NVRAM.

Change the configuration register back to 0x2102 now guide to set up your router correctly launch and load NVRAM contents.

Lab Instruction:

As shown below is a Cisco 2651XM router that has a console password on the device. With such a password you cannot access exec mode without authenticating this password correctly. When buying routers used, you may commonly be faced with scenario.

Router con0 is now available

Press RETURN to get started.

User Access Verification

Password:

Step 1 . Power cycle the router or power on the router first. When the router is started, you need to break into network cards PXE boot ROM to boot the router boot sequence, by holding down the CTRL key and press pause break like you. Repeat this operation until you put the network adapter PXE boot ROM prompt.

System Bootstrap, Version 12.2(8r) [cmong 8r], RELEASE SOFTWARE (fc1)
Copyright (c) 2003 by cisco Systems, Inc.
C2600 platform with 262144 Kbytes of main memory

monitor: command "boot" aborted due to user interrupt
rommon 1 >

Step 2 . When you change the configuration register to boot to Cisco IOS router will ignore the contents of the NVRAM. To set the configuration register to 0x2142 and start the router.

rommon 1 >confreg 0x2142
rommon 2 >reset

Step 3 . The Cisco IOS router initial configuration is started, the system dialog box prompts you, type n and press ENTER, you will be placed in user mode. Now you can put your self into privileged mode, enabled by typing. Once in privileged mode, you can copy the startup configuration to the running configuration, and then manually change the password, and then save the configuration to NVRAM by typing copy run start.

         --- System Configuration Dialog ---

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


Press RETURN to get started!

Router>enable
Router#copy start run
Destination filename [running-config]?
506 bytes copied in 3.868 secs (168 bytes/sec)
IMAROUTER#configure terminal
IMAROUTER(config)#enable secret NEWENABLEPASSWORD
IMAROUTER(config)#line con 0
IMAROUTER(config-if)#password NEWPASSWORD
IMAROUTER(config-if)#end
IMAROUTER#copy run start
Destination filename [startup-config]?
Building configuration...
[OK]
IMAROUTER#

Step 4 . Enter the Cisco IOS router starts, initial configuration of the system dialog box prompts you, type n and press enter here and you will be placed in user mode. Now you can put your self into privileged mode, enabled by typing. Once in privileged mode, you can clear the contents of the NVRAM by issuing the write erase command.

         --- System Configuration Dialog ---

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


Press RETURN to get started!

Router>enable
Router#write erase
Erasing the nvram filesystem will remove all files! Continue? [confirm]
[OK]
Erase of nvram: complete
Router#

Step 5 . Once you have the password reset or NVRAM public health, you need to set the configuration register back to 0x2102 so normal startup and reboot the router loads the contents of the NVRAM or power failure occurs.