Chapter 1 Exam Review

1
Chapter 1 Exam Review

• Exploration Curriculum 2007-2008

2
1.1.2

• ROM is a form of permanent storage. Cisco devices
  use ROM to store
• The bootstrap instructions
• Basic diagnostic software
• Scaled-down version of IOS
• Flash Memory
• Flash memory does not lose its contents when the
  router loses power or is restarted.

3
1.1.4

• The output from the show version command
  includes
• IOS version
• Cisco Internetwork Operating System Software
• IOS (tm) C2600 Software (C2600-I-M), Version
  12.2(28), RELEASE SOFTWARE (fc5)
• This is the version of the Cisco IOS software in
  RAM and that is being used by the router.
• ROM Bootstrap Program
• ROM System Bootstrap, Version 12.1(3r)T2,
  RELEASE SOFTWARE (fc1)
• This shows the version of the system bootstrap
  software, stored in ROM memory, that was
  initially used to boot up the router

4
1.1.4

• Location of IOS
• System image file is "flashc2600-i-mz.122-28.bin"
  
• This shows where the bootstrap program is located
  and loaded the Cisco IOS, and the complete
  filename of the IOS image.
• CPU and Amount of RAM
• cisco 2621 (MPC860) processor (revision 0x200)
  with 60416K/5120K bytes of memory

5
1.1.4

• Interfaces
• 2 FastEthernet/IEEE 802.3 interface(s)
• 2 Low-speed serial(sync/async) network
  interface(s)
• This section of the output displays the physical
  interfaces on the router. In this example, the
  Cisco 2621 router has two FastEthernet interfaces
  and two low-speed serial interfaces.
• Amount of NVRAM
• 32K bytes of non-volatile configuration memory.
• This is the amount of NVRAM on the router. NVRAM
  is used to store the startup-config file.

6
1.1.4

• Amount of Flash
• 16384K bytes of processor board System flash
  (Read/Write)
• Configuration Register
• Configuration register is 0x2102
• The last line of the show version command
  displays the current configured value of the
  software configuration register in hexadecimal.

7
1.1.4

• Enter Setup Mode (Optional). If the startup
  configuration file can not be located, the router
  prompts the user to enter setup mode.

8
1.1.4

• Bootup Process
• There are four major phases to the bootup
  process
• 1. Performing the POST
• 2. Loading the bootstrap program
• 3. Locating and loading the Cisco IOS software
• 4. Locating and loading the startup configuration
  file or entering setup mode

9
1.1.4

• After the IOS is loaded, the bootstrap program
  searches for the startup configuration file,
  known as startup-config, in NVRAM.
• If the startup configuration file does not exist
  in NVRAM, the router may search for a TFTP
  server. If the router does not find the
  configuration in the server it will enter CONSOLE
  mode

10
1.1.4

• The IOS is typically stored in flash memory, but
  can also be stored in other places such as a TFTP
  (Trivial File Transfer Protocol) server.

11
1.1.5
12
1.2.2

• Password can be configured for enteingr
  privileged EXEC mode. Router(config)enable
  secret class
• Passwords can also be configured for the console
  and Telnet lines. The command login enables
  password checking on the line. If you do not
  enter the command login on the console line, the
  user will be granted access to the line without
  entering a password.
• R1(config)line console 0
• R1(config-line)password cisco
• R1(config-line)login
• R1(config-line)exit
• R1(config)line vty 0 4
• R1(config-line)password cisco
• R1(config-line)login
• R1(config-line)exit

13
1.2.2

• The outcome of entering these commandsR1(config)
  line vty 0 4 R1(config-line) password check123
  R1(config-line) login
• sets the password to be used for connecting to
  this router via Telnet

14
1.2.2

• To change interfaces from administratively down
  to up you must issue the no shut command

15
1.2.2

• R1show startup-config
• This command displays the startup configuration
  file stored in NVRAM. This is the configuration
  that the router will use on the next reboot. This
  configuration does not change unless the current
  running configuration is saved to NVRAM with the
  copy running-config startup-config command.

16
1.3.1

• There are three functions of a router
• packet switching
• segmentation of broadcast domains
• selection of best path based on logical addressing

17
1.3.2

• After the router's interface is configured and
  the interface is activated with the no shutdown
  command, the interface must receive a carrier
  signal from another device (router, switch, hub,
  etc.) before the interface state is considered
  "up." Once the interface is "up," the network of
  that interface is added to the routing table as a
  directly connected network.

18
1.4.3

• When a router has multiple paths to a
  destination network and the value of that metric
  (hop count, bandwidth, etc.) is the same, this is
  known as an equal cost metric, and the router
  will perform equal cost load balancing. The
  routing table will contain the single destination
  network but will have multiple exit interfaces,
  one for each equal cost path. The router will
  forward packets using the multiple exit
  interfaces listed in the routing table.
• EIGRP (as well as IGRP) are the only routing
  protocols that can be configured for unequal cost
  load balancing.

19
1.4.5

• What does a router do with a packet received from
  one network and destined for another network? The
  router performs the following three major steps
• Decapsulates the Layer 3 packet by removing the
  Layer 2 frame header and trailer.
• Examines the destination IP address of the IP
  packet to find the best path in the routing
  table.
• Encapsulates Layer 3 packet into a new Layer 2
  frame and forwards the frame out the exit
  interface.

20
1.4.5

• The header address information that the router
  changes in the information it receives from an
  attached Ethernet interface before retransmitting
  it out another interface
• the Layer 2 source and destination address

21
1.2.2

• R1show running-config
• This command displays the current running
  configuration that is stored in RAM. With a few
  exceptions, all configuration commands that were
  used will be entered into the running-config and
  implemented immediately by the IOS.

22
2.1.3

• Two types of cables can be used with Ethernet LAN
  interfaces
• A straight-through, or patch cable, with the
  order of the colored pins the same on each end of
  the cable
• A crossover cable, with pin 1 connected to pin 3,
  and pin 2 connected to pin 6
• Straight-through cables are used for
• Switch-to-router
• Switch-to-PC
• Hub-to-PC
• Hub-to-server
• Crossover cables are used for
• Switch-to-switch
• PC-to-PC
• Switch-to-hub
• Hub-to-hub
• Router-to-router
• Router-to-server