3.1 Cisco Device Connection

Question 1

Boot loader software

Answer 1

A small program located in ROM that runs after the power-on self-test (POST) completes. The boot loader software is used to locate and launch the operating system.

Question 2

Central processing unit (CPU) subsystem

Answer 2

The CPU subsystem is made up of the CPU, the dynamic random-access memory (DRAM), and the flash file system. POST checks the CPU subsystem at device bootup.

Question 3

Non-volatile

Answer 3

Memory that does not lose content when the device is powered down.

Question 4

Power-on-self-test

Answer 4

A series of tests that a device performs when booting.

Question 5

Random access memory (RAM)

Answer 5

Volatile memory that is used in routers to provide temporary storage. It is used for running config files, IP routing tables, ARP tables, and the IOS.

Question 6

Read-only memory

Answer 6

Nonvolatile memory that is used to provide storage for diagnostic software, boot instructions, and some IOS files.

Question 7

Volatile memory

Answer 7

Memory that loses content when the device is powered down.

Question 8

How do you connect to a Cisco switch

Answer 8

For first time connection, you must configure the device locally using the connection port located on the back of the cisco device. Once the device has been configured you can then connect remotely over the network for any future re-configuration needs.

Local Connection:
A local physical connection is required for the initial setup of the device. During this setup, you’ll configure IP addresses, passwords, and other settings. A common connection method used for Cisco devices is the console cable. It is an RJ-45 to DB-9 serial or USB serial cable. There is a blue console port located on the back of Cisco devices. You can connect to this port using the specially designed console cable. This console cable is also called a roll-over cable because the pins that make up the connectors are flipped from end to end. Console cables were originally RJ-45 to serial connections, but because most laptops no longer have serial ports, USB connections have become more common.

Once you have established a physical connection between the computer and the Cisco device, you need to open emulation software on the device. There are several options available including Putty and TeraTerm. You use this software to make a connection through the serial or USB port of the computer. There are no passwords in place by default on the Cisco device. So, activating the connection and pressing the Enter key a couple of times will provide you with a device prompt. The following table shows the requirements for a console connection.

Remote Connection:
The second method for connecting to a Cisco device is remote access. Remote access provides you with access to the device regardless of location. As long as the device has an IP address and is live on the network, you can access the router to get to its configuration screens. You can connect using a terminal emulation program like Telnet, SSH, or even a web browser.

Question 9

What is the operating system used on Cisco devices?

Answer 9

Cisco Internetwork Operating System (IOS)

Question 10

Back Up IOS

Answer 10

If you’re working on a large network and need a backup location, a Trivial File Transfer Protocol (TFTP) server is a great solution. TFTP is a software utility that can be used to send or receive files from a remote system. Cisco IOS software and configuration files can be stored on a TFTP server. This helps to manage the number of IOS images, revisions, and configuration files that need to be managed and maintained across your network. To reduce downtime, create a process for backing up and restoring these images in the event of a corrupted or erased device image.

The steps for backing up an IOS image to a TFTP server are:

1. Verify connectivity to the TFTP server using a ping test.
2. Verify that there is enough space on the server for the IOS software image. This can be done using the show flash0: command.
3. Copy the image to the TFTP server using the copy source-url destination-url command.

Question 11

Upgrade IOS

Answer 11

Cisco is always developing new versions of their IOS operating system. These new versions usually include new features, security updates, and bug fixes. When a new version is released, it’s important for you to understand how to upgrade the operating system on your router.

To begin the upgrade process, copy the IOS image from the TFTP server using the following steps:

1. Select the correct image file either from your TFTP server or from the Cisco site. If you’re pulling from the Cisco site, it is best to store it on your TFTP server for use on additional devices. Be sure to review the naming convention for platform, features, and software.
2. Verify connectivity to the TFTP server using a ping test.
3. Verify that there is enough space on the device that is being upgraded.
4. Copy the IOS image file from the TFTP server using the copy command.

When the image has been saved to the device, configure the router to load this image at startup. This can be done using the boot system command. Be sure to save this configuration so that when you reload the device, the new image will be used. Once you have rebooted, you can verify that the correct image was loaded by using the show version command.

Question 12

c2900-universalk9-mz.SPA.157-3.M5.bin

Answer 12

c2900 - Identifies the platform on which the image runs. In this example, the platform is a Cisco 2900 router.

universal - Indicates that all of the features, turned on and off by a software license is included. Older versions of IOS would have different builds that included different features, which would be indicated by various lettered encoding schemes.

k9 - Includes export controlled cryptography software.

-m - Runs in RAM (memory) as opposed to running directly from flash.

z - Indicates the file as a compressed image.

SPA - Designates that the file has been digitally signed (S), is intended for production (P), and is using key A.

157 - Major Release 15 (Polaris), minor release 7 (aka, 15.7).

-3 - This is the 3rd maintenance release.

M5 - Specifies the version of the IOS including the major release, minor release, maintenance release, and maintenance rebuild numbers. The M indicates this is an extended maintenance release.

.bin - The file extension indicating that this file is a binary executable file

Question 13

You want to make a console connection to a router using the serial port on a PC. Select the necessary components to make the console connection. Select only the necessary components.

Answer 13

1. Console Port
2. Rollover Cable
3. Terminal Emulation Program

To make a console connection, connect the router’s console port to the PC’s serial port with a rollover cable, and then run a terminal emulation program (such as HyperTerminal) on the PC to make the connection.

To connect to a router with a Telnet session connect the router to a PC or to the network using the Ethernet port and an Ethernet cable. The router interface must be assigned an IP address.

Question 14

Match the memory types with the information they store.

Answer 14

RAM stores the running-configuration file, routing tables, and ARP tables.

FLASH stores the Cisco IOS software.

ROM stores POST and the boot loader software.

NVRAM stores the startup-configuration file.

Question 15

You have issued the following command and received the response as shown.

Router#sh start
%%Non-volatile configuration memory has not been set up or has bad checksum

Which of the following is a reason for this response?

Answer 15

This message is shown if no configuration file are saved to NVRAM.

Question 16

Which of the following measures can you implement to help secure access to a router?

Answer 16

1. Set a password and use the login command.
2. Keep the router in a locked room.

To help secure access, set a password and use the login parameter to enable password checking. Because access through the console port must be done locally, users must have physical access to the router in order to make a console connection. Keep the router in a locked room to help control access. If a user has access to the physical device, he or she can gain access, even if a password has been set.

Configure the enable secret password to require a password to enter privileged EXEC mode. This password can be bypassed if physical access to the router is not secured. Use SSH to secure remote access to the router console. Use the service password-encryption command to encrypt passwords in the configuration file.

Question 17

Put the boot sequence process items in order.

Answer 17

1. Power-on self-test checks hardware
2. Boot loader software is loaded
3. IOS is loaded
4. Startup-config is loaded

After a successful power-on-self-test, the device copies the boot loader software, which is sometimes called a bootstrap, from the ROM into RAM and executes it. The bootstrap program initializes the CPU and enables other boot functions. It also determines which IOS image should be used and when to load it.

As the IOS loads from flash memory, the boot loader software turns control of the system over to the operating system.

Then the IOS locates the startup configuration file in NVRAM and loads it into RAM as the running-config file.
At this point, all interfaces are initialized using the commands found in the startup-config file. Everything is loaded into RAM, so the boot sequence is complete.

Question 18

You are the senior network administrator for a large company. A junior administrator from one of your field offices sent you a router that he thinks is faulty. He says the router always uses default settings and boots to setup mode even though he has verified that startup-config contains the correct values.

What is the most likely source of the problem?

Answer 18

The router configuration register is set to bypass startup configuration.

The configuration register can be configured to bypass startup configuration settings. Use Router(config)#config-register 0x2102 to change the configuration register.

Use show version to display the current configuration register setting.

The configuration register for most Cisco devices is normally 0x2102. When configured to bypass startup configuration, the setting will be 0x2142.

Question 19

The configuration register runs during the POST. What does it control?

Answer 19

The configuration register runs during the POST, and it controls how the router boots up.

Question 20

You have made configuration changes to your Cisco device. Now you want to save the changes to use the next time the device is booted up. Which command could you use?

Answer 20

copy run start

If you want to save the changes made to a Cisco device, you need to copy them to the startup-config file to use the next time the device is booted up. You can do this with the copy run start command, which is basically just a shorter version of copy running-config startup-config. This command instructs the device to copy the contents of the running-config file to the startup-config file.

Question 21

You are a field technician for a large company. You have been sent to a remote site to troubleshoot a downed router. When you arrive at the remote site, how will you connect your laptop to the router?

Answer 21

Connect the laptop’s COM/USB port to the router’s console port using a rollover cable.

You can connect a PC directly to a router using a RJ-45-to-DB-9 female DTE rollover cable or an RJ-45 to USB rollover cable.