Foundation Summary

The "Foundation Summary" section of each chapter lists the most important facts from the chapter. Although this section does not list every fact from the chapter that will be on your INTRO exam, a well-prepared CCNA candidate should know, at a minimum, all the details in each "Foundation Summary" section before going to take the exam.

The console, auxiliary, and Telnet passwords all are set separately, as shown in Table 7-7. Table 7-7 CLI Password Configuration

Access From

Password Type

Configuration

Console

Console password

line console 0 login password faith

Auxiliary

Auxiliary password

line aux 0 login password hope

Telnet

vty password

line vty 0 4 login password love

Table 7-8 lists the commands used to manipulate previously typed commands. Table 7-8 Key Sequences for Command Edit and Recall

Keyboard Command

What the User Gets

Up arrow or Ctrl-p

This displays the most recently used command.

Down arrow or Ctrl-n

After moving back into the histroy buffer of previously used commands, this key sequence moves you forward again.

Left arrow or Ctrl-b

This moves the cursor backward in the currently displayed command without deleting characters. (The b stands for back.)

Right arrow or Ctrl-f

This moves the cursor forward in the currently displayed command without deleting characters. (The f stands for forward.)

Table 7-8 Key Sequences for Command Edit and Recall (Continued)

Keyboard Command

What the User Gets

Backspace

This moves the cursor backward in the currently displayed command, deleting characters.

Ctrl-a

This moves the cursor directly to the first character of the currently displayed command.

Ctrl-e

This moves the cursor directly to the end of the currently displayed command.

Esc-b

This moves the cursor back one word in the currently displayed command.

Esc-f

This moves the cursor forward one word in the currently displayed command.

Ctrl-r

This creates a new command prompt, followed by all the characters typed since the last command prompt was written.

Figure 7-10 illustrates the relationships among configuration mode, user exec mode, and privileged exec mode.

Figure 7-10 CLI Configuration Mode Versus Exec Modes

Figure 7-10 illustrates the relationships among configuration mode, user exec mode, and privileged exec mode.

Routers have four types of memory:

■ RAM—Sometimes called DRAM for dynamic random-access memory, RAM is used by the router just as it is used by any other computer: for working storage. The running or active configuration file is stored here.

■ ROM—This type of memory (read-only memory) stores a bootable IOS image, which typically is not used for normal operation. ROM contains the code that is used to boot the router until the router knows where to get the full IOS image or as a backup bootable image, in case there are problems.

■ Flash memory—Either an EEPROM or a PCMCIA card, Flash memory stores fully functional IOS images and is the default location where the router gets its IOS at boot time. Flash memory also can be used to store configuration files on some Cisco routers.

■ NVRAM—Nonvolatile RAM stores the initial or startup configuration file.

The copy command is used to move configuration files among RAM, NVRAM, and a TFTP server. The files can be copied between any pair. The commands can be summarized as follows:

copy {tftp | running-config | startup-config} {tftp | running-config | startup-config}

The first parameter is the "from" location; the next one is the "to" location. (Of course, choosing the same option for both parameters is not allowed.)

Figure 7-11 shows both the old and the new commands used to view configurations.

Figure 7-11 Configuration show Commands

Figure 7-12 shows an example binary breakdown of the default value for the configuration register, which is hexadecimal 2102.

Figure 7-12 shows an example binary breakdown of the default value for the configuration register, which is hexadecimal 2102.

Figure 7-12 Binary Version of Configuration Register, Value Hex 2102

Bit Position, in Decimal Default Binary Value

15

14 13

12

11

10

9 8

7

6

5

4

3

2 1

0

0

0 1

0

0

0

0 1

0

0

0

0

0

0 1

0

Table 7-9 summarizes the use of the configuration register and the boot system command at initialization time.

Table 7-9 summarizes the use of the configuration register and the boot system command at initialization time.

Table 7-9 boot system Command

Boot System Commands

Result

No boot command

Tries loading the following (in order): first file in flash; broadcasts looking for TFTP server and a default filename; IOS in ROM; or uses ROM Monitor.

boot system ROM

IOS from ROM is loaded.

boot system flash

The first file from Flash memory is loaded.

boot system flash filename

IOS with the name filename is loaded from Flash memory.

boot system tftp filename 10.1.1.1

IOS with the name filename is loaded from the TFTP server.

Multiple boot system commands, any variety

An attempt occurs to load IOS based on the first boot command in the configuration. If that fails, the second boot command is used, and so on, until one is successful.

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