4.0 Service-Related Knowledge

Question 1

4.1 Locate and use a text editor such as, Notepad

Answer 1

Notepad++

Question 2

4.2 Locate and use the Windows command prompt

Answer 2

cmd

Question 3

4.3 Locate, configure, and use Terminal Emulation ( Tera Term, Putty)

Answer 3

Port 23 for Telnet or 22 for SSH
Use IP address and port number
Username and password if SSH

Question 4

4.4 Configure networks settings for Ethernet port on laptop (IP address, subnet mask and default gateway) and establish a connection with Ethernet ports on Cisco equipment using correct cable

Answer 4

Network connections > Properties > IPv4 > Properties > Set to whatever
Use console cable, on device manager check which com port you are using, enter that port when trying to connect through Putty

Question 5

4.5 Make a physical connection from laptop to Cisco console port

Answer 5

Use console cable can be Cisco cable or USB mini-B to USB

Question 6

4.6 Connect, configure, and verify operation status of a device interface

Answer 6

Enter global configuration mode by typing configure terminal.
Identify the interface you want to configure by typing interface interface_type interface_number. For example, interface GigabitEthernet0/1.
Configure the interface settings as needed. For example:
interface GigabitEthernet0/1
ip address 192.168.1.1 255.255.255.0
no shutdown

After configuring the interface, verify its status and configuration using various show commands. For example:
Use show interfaces to display information about all interfaces on the device.
Use show ip interface brief to display a summary of interface IP addresses and status.
Use show interface [interface_type interface_number] to display detailed information about a specific interface.
Check the interface status, line protocol status, IP address, and other relevant parameters to ensure correct configuration and operational status.

Save Configuration:
Once you have verified the configuration and interface status, save the configuration to NVRAM using the write memory or copy running-config startup-config command to ensure that the changes persist across device reboots.

Question 7

4.7 Configure and use TFTP and FTP servers (TFTP d32/64, FIlezilla)

Answer 7

practice

Question 8

4.8 Perform software upgrade or downgrade using TFTP, FTP, xmodem, tftpdnld, or USB Storage

Answer 8

practice

Question 9

4.9 Manage configurations via the TCP/IP network

Answer 9

practice

Question 10

4.10 Perform password recovery on a Cisco device

Answer 10

Performing password recovery on a Cisco device involves accessing the device’s ROM Monitor (ROMMON) mode to bypass the configured passwords and regain control of the device.

1. Power Cycle the Device:
   
   • Physically power cycle the device by unplugging it from the power source and plugging it back in.
   • During the boot-up process, press the “Break” key (usually Ctrl+Break or Ctrl+Pause) on the console terminal emulator to interrupt the boot sequence and access ROMMON mode.
   • Note: The exact key combination may vary depending on the terminal emulator and device model.
2. Access ROMMON Mode:
   
   • Once you’ve interrupted the boot sequence, you should see the ROMMON prompt (rommon 1> or rommon>).
   • If you don’t see the ROMMON prompt, repeat step 1 until you successfully interrupt the boot sequence.
3. Change the Configuration Register:
   
   • Check the current configuration register value by typing confreg at the ROMMON prompt and pressing Enter.
   • If the configuration register value is set to 0x2102 or similar, you may need to change it to 0x2142 to bypass the startup configuration. Enter the following command:
     

     confreg 0x2142

   • Press Enter to set the new configuration register value.
4. Reset the Device:
   
   • Reset the device by typing reset or boot at the ROMMON prompt and pressing Enter.
   • The device will now boot with the startup configuration bypassed.
5. Enter Privileged EXEC Mode:
   
   • Once the device boots up, you’ll be prompted with initial setup dialogue. Enter “no” or press Ctrl+C to skip the initial setup.
6. Copy Startup Configuration:
   
   • Enter privileged EXEC mode by typing enable and pressing Enter.
   • Copy the startup configuration to the running configuration by typing:
     

     copy startup-config running-config

7. Change Passwords:
   
   • Enter global configuration mode by typing configure terminal.
   • Change the passwords as needed using the enable secret and username commands.
8. Restore Configuration Register:
   
   • Change the configuration register value back to its original setting to ensure the device boots normally in the future. Enter the following command:
     

     config-register 0x2102

9. Save Configuration:
   
   • Save the configuration changes by typing write memory or copy running-config startup-config.
10. Reboot the Device:
    
    • Reboot the device to ensure the changes take effect. You can do this by typing reload and pressing Enter.

Question 11

4.11a Identify and correct common network problems at Layers 1 and 2 - Serial or ether interface status

Answer 11

1. Check Physical Connections:
   Ensure that cables are securely connected to the appropriate interfaces on both ends.
   Verify that the cables are not damaged or faulty.
   For Ethernet interfaces, check for link status LEDs on both the device and the connected device (switch or router).
2. Verify Interface Status:
   Use the show interfaces command on Cisco devices to check the status of the interfaces.
   Look for interfaces that are in an “up” state and have the appropriate line protocol status (e.g., up/up).
   If an interface is in a down state, troubleshoot further to identify the root cause, which could include cable issues, interface configuration problems, or hardware failures.
3. Troubleshoot Interface Configuration:
   Review the configuration of the interface using the show running-config command.
   Ensure that the interface is correctly configured with the appropriate IP address (for Ethernet interfaces) or encapsulation settings (for serial interfaces).
   Verify that the interface is not administratively shut down (no shutdown command in interface configuration mode).

Question 12

Upgrade Cisco IOS

Answer 12

Open tftp server (tftpd32)
download IOS Image
copy IOS from tftp server ->

copy tftp: flash:

<IP>
<name>

check whats in flash memory
dir flash:

go to global config then remove old IOS from boot sequence and set new:
no boot system flash:/<old>
boot system flash:/<new>

save new configuration:
copy run start (copy running-config startup-config)
</new></old></name></IP>

Question 13

check whats in flash memory

Answer 13

dir flash:

Question 14

delete file from flash

Answer 14

del flash:/<name></name>

Question 15

Reset password on Cisco IOS

Answer 15

Use the “pause/break or control/break” or “ctrl + Fn + P” key (or equivalent keys) on keyboard to enter ROMmon (ROM Monitor)

Power down, remove compact flash, power on and reboot

type “confreg 0x2142” (configuation registry utility)

power off device, re-insert compact flash, power on and reboot
do NOT enter initial config (starup-config)

enter priviledged exec mode
copy startup-config running-config

enter global config:
conf t
no enable secret
enable secret <pass>
username <name> password <pass></pass></name></pass>

change configuration register:
config-register 0x2102

show version to confirm

save:
copy running-config startup-config

reboot:
reload

Question 16

configuration register 0x2142

Answer 16

Load up IOS but not startup-config

Question 17

Factory Reset Cisco IOS Switch

Answer 17

Power off device (unplug)
Press down the “Mode” button and power back on
Keep Mode held down until you see an amber light

On terminal you should see just
switch:
flash_init

check flash ->
dir flash:

delete vlans and config then boot ->
del flash:vlan.dat
del flash:config.txt
boot

Different equipment may have different procedure, google and read manuals for your specific device

Question 18

4.11b Identify and correct common network problems at Layers 1 and 2 - Ethernet Layer 2

Answer 18

1. Check Duplex and Speed Settings:
   Verify that the duplex and speed settings on both ends of the Ethernet link match.
   Mismatched duplex or speed settings can lead to performance issues and packet loss.
   Use the show interfaces command to check the duplex and speed settings of the interfaces.
2. Configure Auto-Negotiation:
   Whenever possible, configure interfaces to use auto-negotiation to automatically determine the best duplex and speed settings.
   Auto-negotiation allows devices to negotiate the highest possible performance settings based on their capabilities.
3. Manually Set Duplex and Speed:
   If auto-negotiation is not supported or not functioning correctly, manually configure duplex and speed settings on both ends of the link.
   Use the duplex and speed commands in interface configuration mode to set the desired settings.

Question 19

4.11c Identify and correct common network problems at Layers 1 and 2 - WAN Serial Loopback Test:

Answer 19

1. Perform Loopback Test:
   Use loopback testing to verify the functionality of WAN serial interfaces, such as T1 or E1 circuits.
   Configure loopback testing on the interface using the appropriate command (loopback or test command) depending on the type of test required (local loopback or remote loopback).
2. Check Loopback Status:
   After configuring the loopback test, check the status of the interface to verify that the loopback test is active.
   
   • Use the show interfaces command to check the status of the interface and look for indications that the loopback test is active.
3. Verify Loopback Test Results:
   Once the loopback test is complete, verify the test results to ensure that data is successfully looped back to the device.
   Check for any errors or anomalies in the test results that may indicate issues with the WAN circuit or interface.

Question 20

backup config to tftp server

Answer 20

copy startup-config tftp:
Address of Host -> Your IP
Name File

Question 21

upgrade/downgrade Cisco IOS

Answer 21

copy upgrade/downgrade into flash
in global config mode type:
no boot system flash:/[old ios]
boot system flash:/[new ios]

Then save config and reboot

copy running-config startup-config
reload

Question 22

Recovery password from router

Answer 22

power off router
remove compact flash (forces into ROMMON mode)

confreg 0x2142
Load IOS but not startup-config
turn device off, enter compact flash then reboot

no to configure dialog

copy startup-config running-config

create new password
enable secret \_\_\_\_

create new username and password
username [user] password [pass]

change configuration register back
config-register 0x2102

save config
copy running-config startup-config

reboot
reload