Ccna2 M2 Introduction To Router

CCNA – Semester2

Module 2 Introduction to Router

Objectives

• Function and operation of IOS • Establishing session and log into router • CLI help features

Operating Cisco IOS Software

Purpose of Cisco IOS Software

• Basic routing and switching functions • Reliable and secure access to networked resources • Network scalability

Router user interface • The Cisco IOS software uses a command-line interface (CLI) as the traditional console environment. • This environment is accessible through several methods: – Console – AUX – Telnet

Router user interface modes • •

The Cisco (CLI) uses a hierarchical structure. Each configuration mode is indicated with a distinctive prompt and allows only commands that are appropriate for that mode. The IOS provides a command interpreter service known as the command executive (EXEC).

User EXEC and Privileged EXEC • The user EXEC mode allows only a limited number of basic monitoring commands. This is often referred to as a “view only” mode. • The privileged EXEC mode accesses all router commands. This mode can be configured to require a password from the user before accessing it.

Operating Environment

• The ROM monitor performs the bootstrap process and provides low-level functionality and diagnostics. It is used to recover from system failures and to recover a lost password. • Boot ROM mode use a limited subset of the Cisco IOS feature set, is used primarily to replace Cisco IOS image that is stored in flash.

Check for IOS • To see the IOS image and version that is running, use the show version command, which also indicates other system settings. • The show flash command is used to verify that the system has sufficient memory to load a new Cisco IOS image

Command: show version ROM: System Bootstrap, Version 11.0(10c), SOFTWARE BOOTFLASH: 3000 Bootstrap Software (IGS-BOOT-R), Version 11.0(10c), RELEASE SOFTWARE (fc1) LAB_A uptime is 0 minutes System restarted by reload System image file is "flash:c1700-ny-mz.122-13.T8.bin", booted via flash cisco 2500 (68030) processor (revision N) with 6144K/2048K bytes of memory. Processor board ID 09218746, with hardware revision 00000000 Bridging software. X.25 software, Version 2.0, NET2, BFE and GOSIP compliant. 1 Ethernet/IEEE 802.3 interface(s) 2 Serial network interface(s) 32K bytes of non-volatile configuration memory. 8192K bytes of processor board System flash (Read ONLY) Configuration register is 0x2102

Command: show flash System flash directory: File Length Name/status 1 5895768 c1700-ny-mz.122-13.T8.bin [5895832 bytes used, 2492776 available, 8388608 total] 8192K bytes of processor board System flash (Read ONLY)

Starting a Router

Router Startup Sequence

Setup Mode • Setup is not intended as the mode for entering complex protocol features in the router. • Setup mode is to install a minimal configuration for a router, unable to locate a configuration from another source. • Setup mode is called when there is no configuration file at startup or when user issue setup command

Setup Mode

• •

At startup, if you see the question “Would you like to enter the initial configuration dialog?”, answer no. Jump out of setup mode without saving by pressing Ctrl+C

Router LED indicators • Cisco routers use LED indicators to provide status information. • An interface LED indicates the activity of the corresponding interface. • The green OK LED will be on after the system initializes correctly.

Initial Bootup

Logging into the router User Mode

Interface config

Privileged Mode

Line config

Config Mode

Router config

• A user must login to the router before any other commands are entered.

Keyboard help in the router CLI • Typing a question mark (?) displays a handy list of available commands. • The "--More--" prompt at the bottom of the display indicates that multiple screens are available as output. Press the Spacebar to view the next page, or Enter key to view the next line. • The dollar sign ($) indicates that the line has been scrolled to the left.

Editing and History Functions

Router command history • With the command history feature, the following tasks may be completed: – Set the command history buffer size – Recall commands – Disable the command history feature

• terminal history size or the history size {0-256} : change the number of command lines the system records during a terminal session (default is 10)

Summary • • • • •

Purpose and operation of IOS IOS naming convention CLI: use EXEC and privileged EXEC mode CLI help and editing command Show version

CCNA2 – Module2