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: