1. What are the two different names for the router's mode of operation that when accessed allow you to issue commands that could be disruptive to router operations?
Enable and privileged. Both are commonly used and found in Cisco documentation.
2. What are three methods of logging on to a router?
Console, auxiliary port, Telnet. All three cause the user to enter user mode.
3. What is the name of the user interface mode of operation used when you cannot issue disruptive commands?
User mode.
4. Can the auxiliary port be used for anything besides remote modem user access to a router? If so, what other purpose can it serve?
Yes-Direct attachment of a terminal (such as the console), and dial for the purpose of routing packets. Although originally created to support remote admin access, many customers use it for dial back-up, particularly when analog lines are desired or when that is all that is available.
5. How many console ports can be installed on a Cisco 7500 router?
One. This is a purposefully strange question. You do not order the console port; every router comes with one, and only one. So, technically, you do not even order one, it is implied by ordering the router.
6. What command would you use to receive command help if you know the show command option that you cannot recall begins with a "C"?
show c?
The help would appear immediately after the you typed the? symbol. You would not need to type "return" after the?.
7. While you are logged in to a router, you issue the command copy? and get a response of "Unknown command, computer name, or host." Offer an explanation as to why this error message appears.
User mode
The user must be in enable/privileged mode to use the copy command. When in user mode, the router does not provide help and treats the command as if there is no such command!
8. Is the number of retrievable commands based on the number of characters in each command, or is it simply a number of commands, regardless of their size?
Number of commands. The length (that is, number of characters) of each command does not affect the command history buffer.
9. How can you retrieve a previously used command? (Name two ways.)
Ctrl-P and "up-arrow."
"Up-arrow" refers literally to the up arrow key on the keyboard. Not all terminal emulators support Ctrl-P or "up-arrow," so recalling both methods is useful.
10. Instead of show ip route, which is the only command you typed since logging into the router, you now want to issue a show ip arp command. What steps would you take to do so, without simply typing show ip arp?
Up-arrow, backspace five times, type arp. The up-arrow retrieves the show ip route command. Backspace moves the cursor backward and erases the character. Typing inserts the characters into the line, but the cursor is at the end of the line.
11. After typing show ip route 128.1.1.0, you now want to issue the command show ip route 218.1.4.0. What steps would you take to do so, without simply typing show ip route 218.1.4.0?
Up-arrow, Ctrl-B (or left arrow) twice, backspace once, type 4. The Ctrl-B and left arrow keys back up one character in the line, without deleting the character. Backspace deletes the "1" in this case. Typing inserts into the line.
12. What configuration command causes the router to demand a password from the console? What configuration mode "context" must you be in; that in, what command(s) must you type before this command?
line console 0
login
The line console 0 command is a context setting command; it adds no information to the configuration in and of itself. The login command, which follows the line console 0 command, tells the IOS that a password prompt is desired at the console.
13. What configuration command is used to tell the router the password that is required at the console? What configuration mode "context" must you be in; that is, what command(s) must you type before this command?
password xxxxxxx
line console 0
The password command tells the IOS the value that should be typed when a user wants access from the console. This value is requested of you by the lOS because of the login command. It must be typed while in console configuration mode, which is reached by typing line console 0.
14. What is the purpose of Flash memory in a Cisco router?
To store IOS and microcode files; to allow remote loading of new versions of these files. In most routers, only an IOS is found. If microcode is upgraded, the files reside in flash memory.
15. What is the intended purpose of NVRAM memory in a Cisco router?
To store a single configuration file, used at router load time. NVRAM does not support multiple files.
16. What does the NV stand for in NVRAM?
Nonvolatile
NVRAM is battery powered if it is really RAM. In some routers, Cisco has (sneakily!) used a small portion of Flash for the purpose of NVRAM, but Cisco would not ask such trivia on the test!
17. What is the intended purpose of RAM in a Cisco router?
For storing working IOS memory (such as routing tables or packets) and for IOS code storage. In some router models, not all the IOS is copied into RAM. Some of the IOS is left in flash memory so that more RAM is available for working memory.
18. What is the purpose of ROM in a Cisco router?
To store a small IOS
Typically, this IOS is used only during maintenance or emergencies.
19. What configuration command would be needed to cause a router to use an IOS image named c2500-j-l.112-14.bin on TFTP server 128.1.1.1 when the router is reloaded? If you forgot the first parameter of this command, what steps must you take to learn the correct parameters and add the command to the configuration? (Assume you are not logged in to the router when you start.)
boot config 128.1.1.1 c25GG.j.1.112-14.bin
As for the second part of the question: Log in from con/aux/telnet, enable, type the enable password, configure terininal, type boot ? and help appears.
20. What command sets the password that would be required after typing the enable command? Is that password encrypted by default?
enable or enable secret
The password in the enable command is not encrypted by default. The enable secret password is encrypted.
21. What is missing from the configuration command banner "This is Ivan Denisovich's Gorno Router-Do Not Use" for it to have the correct syntax?
A delimiter character that is not part of the banner at the beginning and end of the text. For example:
banner # This is Ivan.... Do Not Use #
22. Name two commands that affect the text used as the command prompt.
hostname and prompt
23. When using setup mode, you are prompted at the end of the process as to whether you want to use the configuration parameters you just typed in. Which type of memory is this configuration stored into if you type yes?
Both NVRAM and RAM
This is the only router IOS command that modifies both the active and startup configuration files as the result of one action by the user!
24. What two methods could a router administrator use to cause a router to load the IOS stored in ROM?
Setting the configuration register boot field to binary 0001, or adding boot system rom to the configuration file and copying it to the startup configuration file. To set the configuration register to hex 2101, which would yield binary 0001 in the boot field, the config-register 0x2101 global configuration command would be used.
25. What could a router administrator do to cause a router to load file xyz123.bin from TFTP server 128.1.1.1 upon the next reload? Is there more than one way to accomplish this?
boot system 126.1.1.1 xyz123.bin
This is the only way to make the router load this file from the TFTP server.
26. What is the process used to update the contents of flash memory so that a new lOS in a file called c2500-j-l.112-14.bin on TFFP server 128.1.1.1 is copied into flash memory?
copy tftp flash
The other details, namely the IP address of the TFTP server and the filename, are requested via prompts to the user.
27. Name three possible problems that could prevent the command boot net c2500-j-l.112-14.bin 128.1.1.1 from succeeding.
The possible reasons include: 128.1.1.1 is not accessible through the network; there is no TFTP server on 128.1.1.1; the file is not in the TFTP default directory; the file is corrupted; a boot command could precede this boot command in the configuration file, and the IOS referenced in the first boot command would be used instead.
28. Two different IOS files are in a router's flash memory, one called c2500-j-l.111-3.bin and one called c2500-j-l.112-14.bin. Which one does the router use when it boots up? How could you force the other IOS file to be used? Without looking at the router configuration, what command would you use to discover which file was used for the latest boot of the router?
The first IOS file listed in the show flash command is the one used at reload time, unless a boot system command is configured. Configuration command boot system flash xyz123.bin would override the order in flash memory. show version is the command used to display the filename of the 105 for the latest reload of a router. The show version dutput tells you the version, as well as the name of the file that was used at last reload time. It is particularly difficult to find in the output of the command.
29. What does CDP stand for?
Cisco Discovery Protocol
CDP is Cisco proprietary and is not dependent on a particular Layer 3 protocol to be configured and working.
30. What type of interfaces is CDP enabled on by default? (Assume IOS 11.0 and beyond.)
On all interfaces that support SNAP headers. These include LANs, Frame Relay, and ATM.
31. What command can be used to provide as much detailed information as is possible with CDP?
show cdp neighbor detail
32. Is the password required at the console the same one that is required when Telnet is used to access a router?
No. The Telnet ("virtual terminal") password is not the same password, although many installations use the same value.
33. How could a router administrator disable CDP? What command(s) would be required on a Cisco 2501 (2 serial, 1 Ethernet) router?
no cdp enable
The cdp enable command is an interface subcommand. So, to disable on a 2501, once in configuration mode, type: interface ethernet 0; then no cdp enable; then interface serial 0, no cdp enable; then interface serial 1, and finally no cdp enable.
34. Which IP routing protocols could be enabled using setup?
RIP and IGRP
35. Name two commands used to view the configuration to be used at the next reload of the router. Which one is a more recent addition to the IOS?
show config and show startup-config
show startup-config is the newer one. And, hopefully, show startup-config is easier to remember.
36. Name two commands used to view the configuration that is currently used in a router. Which one is a more recent addition to the IOS?
write terminal and show running-config
show running-config is the newer command. And, hopefully, show running-config is easier to remember.
37. The copy startup-config running-config command always changes the currently used configuration for this router to exactly match what is in the startup configuration file. (TIF). Why?
False
Some configuration commands do not replace an existing command, but are simply added to a list. If such a list exists, this command simply adds those to the end of the list. Many of these lists in a router configuration are order dependent.