Presentation on theme: "Routers A router is a computer Computers have four basic components:"— Presentation transcript:
1 Routers A router is a computer Computers have four basic components: a CPU,memory,interfaces, anda busThe router is a computer that selects the best paths, and manages the switching of packets between two different networks
3 Router - internal components RAM/DRAMStores routing tables, ARP cache, fast-switching cache, packet buffering (shared RAM), and packet hold queues.also provides temporary and/or running memory for the router’s configuration file while the router is powered on.RAM content is lost when you power down or restart.
4 Router - internal components NVRAMnon-volatile RAMstores a router’s backup/start-up configuration file;content remains when you power down or restart
5 Router - internal components Flasherasable, reprogrammable ROMholds the operating system image and microcodeallows you to update software without removing and replacing chips on the processorcontent remains when you power down or restartmultiple versions of IOS software can be stored in Flash memory
6 Router - internal components ROMcontains power-on diagnostics,a bootstrap program, andoperating system softwaresoftware upgrades in ROM require replacing pluggable chips on the CPU
7 Router - internal components Interfacenetwork connection through which packets enter and exit a routerit can be on the motherboard or on a separate interface module
9 Router Configuration A router is made up of configurable components. A router has modesexamining,maintaining, andchanging the components.
10 Router Configuration show commands are used for examination. You use cdp to show entries about neighbours.You access other routers by using telnet.You test network connectivity layer by layer.Testing commands include ping, trace, telnet, and debug
11 Router Configuration A router can be configured from many locations: Upon initial installation, it is configured from the console terminal. The console terminal is a computer connected to the router through the console port.It can be connected via modem by using the auxiliary port.After it is installed on the network, it can be configured from Virtual Terminals 0 through 4.Files can also be downloaded from a TFTP server on the network
12 Router ModesWhether accessed from the console or by a Telnet session through a TTY port, the router can be placed in several modes.Each mode provides different functions:User EXEC modePrivileged EXEC modeSet-up modeGlobal configuration modeOther configuration modesRXBOOT mode
13 Router Modes User EXEC mode Privileged EXEC mode A “look-only” mode in which the user can view some information about the router, but cannot change anything.Privileged EXEC modeSupports the debugging and testing commands, detailed examination of the router, manipulation of configuration files, and access to configuration modes.
14 Router Modes Set-up mode Global configuration mode Presents an interactive prompted dialog at the console that helps the new user create a first-time basic configuration.Global configuration modeImplements powerful one-line commands that perform simple configuration tasks.
15 Router Modes Other configuration modes RXBOOT mode Provide more detailed multiple-line configurations.RXBOOT modeA maintenance mode that can be used, among other things, to recover lost passwords.
16 Router Status Commands show versionDisplays the configuration of the system hardware,the software version,the names and sources of configuration files, andthe boot image.show processesDisplays information about the active processes.
17 Router Status Commands show protocolsDisplays the configured protocols.This command shows the status of all configured Layer 3 protocols.show memShows statistics about the router’s memory, including memory free pool statistics.
18 Router Status Commands show stacksMonitors the stack use of processes and interrupt routines and displays the reason for the last system reboot.show buffersProvides statistics for the buffer pools on the router.show flashShows information about the Flash memory device.
19 Router Status Commands show running-configDisplays the active configuration file.show startup-configDisplays the backup configuration file.show interfacesDisplays statistics for all interfaces configured on the router.
20 Cisco Discovery Protocol (CDP) CDP provides a single proprietary command that enables network administrators to access a summary of what the configurations look like on other directly connected routers.CDP runs over a data link layer connecting lower physical media and upper-network-layer protocols.
21 CDPBecause CDP operates at this level, CDP devices that support different network-layer protocols can learn about each other.CDP starts up automatically at boot up. CDP can then automatically discover neighbouring Cisco devices running CDP.
22 CDP Discovered devices extend beyond those having TCP/IP. CDP discovers directly connected Cisco devices regardless of which Layer 3 and 4 protocol suite they run.
23 CDPCDP provides information about each CDP neighbour device. Values include the following:Device identifiers—For example, the router’s configured host name and domain name (if any)Address list—At least one address for SNMP, up to one address for each protocol supportedPort identifier—Such as Ethernet 0, Ethernet 1, and Serial 0Capabilities list—If, for example, the device acts as a source route bridge as well as a routerVersion—Information such as that provided by the local command show versionPlatform—The device’s hardware platform; for example, Cisco 7000
24 Cisco Router Configuration We have seenshow andcdp commandsshow startup-config - display the backup configuration fileshow running-config—display active configuration file.
25 Cisco Router Configuration erase startup-config - deletes the backup configuration file in NVRAM.reload - reloads the router, causing it to run through the entire configuration process.Setup - to enter setup mode from the privileged EXEC prompt.
26 Cisco Router Configuration configure terminal—Configures manually from the console terminal.copy tftp running-config—Loads configuration information from a network TFTP server.copy running-config startup-config— Stores the current configuration from RAM into NVRAM.
27 Cisco Router Configuration copy running-config tftp — Stores the current configuration from RAM on a network TFTP server.
29 Cisco Router Configuration Specific configuration modes:interface mode - for configuring interfacessubinterface mode - for configuring multiple virtual interfaces on a single physical interfaceline mode - for configuring the operation of a terminal linerouter mode - for configuring an IP routing protocoletc.
30 Cisco Router Configuration Configuring router identificationRouter# config termRouter(config)# hostname LABALABA#ctrl-z : back to privileged exec modeexit : back out one level
31 Cisco Router Configuration Message of the day bannerLABA(config)#banner motd # message #Interface descriptionLABA(config)#interface ethernet 0LABA(config-if)#description my LAN, BG
35 Configuring interfaces LABA(config)#int s 0LABA(config-if)#clock rate 56000clk rate is set for DCEsLABA(config-if)#bandwidth 56no clock rate removes clock rateshut down/no shut down
36 Configuring routing protocols LABA(config)#router ripLABA(config-router)#networkLABA(config-router)# networkLABA(config-router)#ctrl-zLABA(config)#ctrl-zLABA#show ip protocolLABA#show ip route [routing table]
37 Configuring routing protocols LABA>show ip interfacesLABA#debug ip rip
38 Exercise - Configuring LABA Hostname:Router>enapassword:Router#config termRouter(config)#hostname lab-a
39 Exercise - Configuring LABA Enable secret password - classlab-a(config)#enable secret class
40 Exercise - Configuring LABA All appropriate interfaces with IP addresses and subnet maskslab-a(config)#int s 0lab-a(config-if)#ip addresslab-a(config-if)#clockrate 56000lab-a(config-if)#bandwidth 56
41 Exercise - Configuring LABA lab-a(config)#int e 0lab-a(config-if)#ip addresslab-a(config-if)#bandwidth 56lab-a(config)#int e 1lab-a(config-if)#ip address
42 Exercise - Configuring LABA Configure riplab-a(config)#router riplab-a(config)#networklab-a(config)# networklab-a(config)# network