1

cisco internetwork

- configuration

- osi - LAN VLAN - IP addressing host configuration -

network

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router cisco internetwork internetwork (IOS) configuration cisco router router configuration register password router - Cisco IOS - Cisco configuration - CDP Telnet - hostnames - ping traceroute

Cisco router 9.1 Cisco router

Component Description

Bootstrap ROM IOS Post ROM post router Rom monitor ROM , , Mini IOS RXBOOT bootloader Cisco mini IOS rom

Cisco IOS flash memory RAM packet buffer,ARP cache ,routing table IOS RAM ROM router Flash memory routerm Cisco IOS flash memory router EEPROM intel NVRAM router switch NVRAM router switch Configuration router register 0x02102 router IOS flash memory router

NVRAM

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router router boot sequence

1. router POST POST hardware router

POST ROM() 2. bootstrap cisco IOS bootstrap bootstrap

IOS flash memory cisco router

3. IOS NVRAM startup-config running-config NVRAM

4. startup-config NVRAM router startup-config NVRAM router bootup

configuration registers Router cisco 16 NVRAM configuration register cisco IOS flash memory NVRAM configuration register password router

configuration register Configuration register 16 15 0 0x02102 13 , 8 , 1 1 9.2 2 4 8 , 4 , 2 , 1 TABLE 9 . 2 The Configuration Register Bit Numbers

Configuration Register 2 1 0 2

Bit number 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Binary 0 0 1 0 0 0 0 1 0 0 0 0 0 0 1 0

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9.3 6 password NVRAM

Bit 16

0-3 0x000-0x00F boot field 6 0x0040 NVRAM 7 0x0080 OEM 8 0x101 break 10 0x0400 IP broadcast 0 5,11-12 0x0800-0x1000 13 0x2000 ROM 14 0x4000 IP broadcast 15 0x8000 NVRAM

boot field 0-3 configuration register router 9.4 boot field

Boot Field Meaning

00 ROM monitor mode ROM monitor mode configuration register register 2100 01 ROM IOS ROM configuration register 2101 02-F 2102-210F router NVRAM

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Configuration Register

Router#sh version Cisco Internetwork Operating System Software IOS (tm) C2600 Software (C2600-I-M), Version 12.1(8)T3, RELEASE SOFTWARE (fc1) [output cut] Configuration register is 0x2102

configuration register 0x2102 configuration register NVRAM IOS 12.1(8)T3.

Configuration Register configuration register configuration register

- ROM monitor mode - source - break - broadcast address - console terminal - ROM - TFTP server

Router(config)#config-register 0x101 Router(config)#^Z Router#sh ver [output cut] Configuration register is 0x2102 (will be 0x0101 at next reload)

configuration register 0x101

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password password configuration register 6 NVRAM configuration 0x2102 6 router configuration NVRAM password 6 NVRAM 6 0x2142 password - router break - configuration register 6 ( 0x2142) - router - - - password - configuration - configuration - router -

break Ctrl+Break router reboot

System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1) Copyright (c) 1999 by cisco Systems, Inc. TAC:Home:SW:IOS:Specials for info PC = 0xfff0a530, Vector = 0x500, SP = 0x680127b0 C2600 platform with 32768 Kbytes of main memory PC = 0xfff0a530, Vector = 0x500, SP = 0x80004374 monitor: command "boot" aborted due to user interrupt rommon 1 >

rommon1>prompt router

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configuration register configuration register config-register 6 configuration register 0x2142 Cisco 2600 Series router Cisco 2600 series rommon1>prompt Cisco 2500 Series configuration register router 2500 series type break configuration register Configuration register o/r register 6 router 2501

System Bootstrap, Version 11.0(10c), SOFTWARE Copyright (c) 1986-1996 by cisco Systems 2500 processor with 14336 Kbytes of main memory Abort at 0x1098FEC (PC) 239 >o Configuration register = 0x2102 at last boot Bit# Configuration register option settings: 15 Diagnostic mode disabled 14 IP broadcasts do not have network numbers 13 Boot default ROM software if network boot fails 12-11 Console speed is 9600 baud 10 IP broadcasts with ones 08 Break disabled 07 OEM disabled 06 Ignore configuration disabled 03-00 Boot file is cisco2-2500 (or 'boot system' command) >o/r 0x2142

03-00 router boots router file flash memory configuration register IOS-name

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router - router 2600 series ,type reset - router 2500 series ,type

Router setup No setup enter

configuration password router startup config running - config

copy startup-config running-config or use the shortcut copy start run 440 Configuration running RAM

password config t enable secret todd

configuration register router password configuration register config-register

config t config-register 0x2102

configuration start-config Start config reload router

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Cisco IOS upgrade restore Cisco IOS TFTP host TFTP host ,,flash memory router cisco IOS flash memory cisco IOS flash memory TFTP host IOS TFTP flash memory IOS - network server - network server code - port router 9.1 router 9.1 IOS router

- TFTP server - router crossover cable - subnet router - flash tftp IP address router flash - flash flash memory

flash memory upgrade Cisco IOS router IOS

flash memory flash memory flash Router#sh flash System flash directory: File Length Name/status 1 8121000 c2500-js-l.112-18.bin [8121064 bytes used, 8656152 available, 16777216 total] 16384K bytes of processor board System flash (Read ONLY) Router#

flash memory 16 MB router IOS Memory 8 MB

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c2500-js-1.11.2-18.bin. - c2500 - J image - S - L flash memory - 11.2-18 - class IOS flash 16,384 KB 10MB flash memory IOS

IOS , ,, - f flash - m RAM - r ROM - l - z zip - x mzip

Cisco IOS cisco IOS TFTP server copy flash tftp source IP address TFTP server TFTP ping router

Router#ping 192.168.0.120 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.0.120, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms

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ping TFTP IP copy flash tftp IOS TFTP server

Router#copy flash tftp System flash directory: File Length Name/status 1 8121000 c2500-js-l.112-18.bin [8121064 bytes used, 8656152 available, 16777216 total] Address or name of remote host [255.255.255.255]? 192.168.0.120 Source file name?c2500-js-l.112-18.bin

Destination file name [c2500-js-l.112-18.bin]?[Enter] Verifying checksum for 'c2500-js-l.112-18.bin')file #1) ...OK Copy '/c2500-js-l.112-18' from Flash to server as '/c2500-js-l.112-18'? [yes/no]y !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!! [output cut] Upload to server done Flash copy took 00:02:30 [hh:mm:ss] Router#

output flash memory copy flash memory TFTP server addess host IP ADDRESS TPTP Source flash memory

Cisco router IOS cisco IOS flash memory IOS download TFTP server flash memory copy tftp flash IP address TFTP server download flash memory TFTP host TFTP restore TFTP server TFTP

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copy tftp flash router ROM base IOS image

Router#copy tftp flash **** NOTICE ****

Flash load helper v1.0 This process will accept the copy options and then terminate the current system image to use the ROM based image for the copy. Routing functionality will not be available during that time. If you are logged in via telnet, this connection will terminate. Users with console access can see the results of the copy operation.

---- ******** ---- Proceed? [confirm][Enter]-

routers router

System flash directory: File Length Name/status 1 8121000 /c2500-js-l.112-18 [8121064 bytes used, 8656152 available, 16777216 total]

Address or name of remote host [192.168.0.120]?[Enter] router TFTP server address Enter flash memory TFTP server

Source file name?c2500-js56i-l.120-9.bin

Destination file name [c2500-js56i-l.120-9.bin]?[Enter] Accessing file 'c2500-js56i-l.120-9.bin' on 192.168.0.120 ... Loading c2500-js56i-l.120-9.bin from 192.168.0.120 (via Ethernet0): ! [OK]

flash memory

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flash memory copy run start router

Erase flash device before writing? [confirm][Enter] Flash contains files. Are you sure you want to erase?

[confirm][Enter] System configuration has been modified. Save? [yes/no]: y Building configuration... [OK] Copy 'c2500-js56i-l.120-9.bin' from server as 'c2500-js56i-l.120-9.bin' into Flash WITH erase? [yes/no] y

router small IOS ROM memory flash TFTP server flash memory

%SYS-5-RELOAD: Reload requested %FLH: c2500-js56i-l.120-9.bin from 192.168.0.120 to flash ... System flash directory: File Length Name/status 1 8121000 /c2500-js-l.112-18 [8121064 bytes used, 8656152 available, 16777216 total] Accessing file 'c2500-js56i-l.120-9.bin' on 192.168.0.120 ... Loading c2500-js56i-l.120-9.bin .from 192.168.0.120 (via Ethernet0): ! [OK] Erasing device... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee eeeeeeeeeeeeeeeeeeeeee Loading c2500-js56i-l.120-9.bin from 192.168.0.120 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! [output cut]

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flash memory transfer

[OK - 10935532/16777216 bytes] Verifying checksum... OK (0x2E3A) Flash copy took 0:06:14 [hh:mm:ss] %FLH: Re-booting system after download

flash memory router

IOS

cisco configuration configuration running-config copy run start running-config router configuration

configuration router Switch TFTP server configuration

configuration cisco router configuration TFTP server Copy running config tftp copy start up config Tftp configuration router DRAM NVRAM 447

configuration configuration DRAM shown running config

Router#sh run Building configuration... Current configuration: ! version 12.0

Configuration router 12.0 IOS

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configuration configuration NVRAM

Show startup config Router#sh start Using 366 out of 32762 bytes ! version 11.2 2 366 NVRAM 32 KB

configuration 11.2 running - config to startup - config upgrade router running config config running config startup config 2

configuration NVRAM running config NVRAM output IOS 12.0

11.2 copy run start router 12

Router#copy run start

Destination filename [startup-config]?[Enter] Warning: Attempting to overwrite an NVRAM configuration previously written by a different version of the system image. 448 Chapter 9 _ Managing a Cisco Internetwork Overwrite the previous NVRAM configuration? [confirm][Enter] Building configuration... [OK] Now when you run show startup-config, the version shows 12.0: Router#sh start Using 487 out of 32762 bytes ! version 12.0

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Configuration TFTP Server

file nvram 2 tftp copy running- config tftp (copy run tftp), .

Router#copy run tftp Address or name of remote host []?192.168.0.120 Destination filename [router-confg]?todd1-confg !! 487 bytes copied in 12.236 secs (40 bytes/sec) Router#

, 2 exclamation point (!!),20 packet (10 packets 1 exclamation point) .. file todd1-config set hostname router. hostname config hostname extention config file .

Restoring Cisco Router Configuration running config router restore config version

startup config copy startup-config running-config ( copy start run) cisco config MEM restore configulation. running config NVRAM . backup routers configulation tftp server backup restore copy tftp startup-config ( copy tftp start) ( function config net)

Router#copy tftp run Address or name of remote host []?192.168.0.120 Source filename []?todd1-confg

Destination filename [running-config]?[Enter] Accessing tftp://192.168.0.120/todd1-confg... Loading todd1-confg from 192.168.0.120 (via Ethernet0): !! [OK - 487/4096 bytes] 487 bytes copied in 5.400 secs (97 bytes/sec) Router#

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00:38:31: %SYS-5-CONFIG: Configured from tftp://192.168.0.120/todd1-confg Router#

configuration file ASCII text file configuration tftp

server router file text editor.

configuration tftp server routers ram interface shutdown interface shutdown.

configuration startup config cisco router, erase startup-config,

Router#erase startup-config Erasing the nvram filesystem will remove all files!

Continue? [confirm][Enter] [OK] Erase of nvram: complete Router#

NVRAM router. boots run setup mode.

Cisco Discovery Protocol (CDP) CDP protocolCisco

CDP protocol CDP TimerCDP command

CDP Timers Holdtime show cdp(sh cdp)CDP ParameterCisco

- CDP timer CPD interfaces - CDP holdtime

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CiscorouterCisco. Router#sh cdp Global CDP information: Sending CDP packets every 60 seconds Sending a holdtime value of 180 seconds Router#

cdp timer,cdp holdtimecdp timercdp holdtime router Router#config t 1 CNTL+Z

Router(config)#cdp ? holdtime Specify the holdtime (in sec) to be sent in

packets timer Specify the rate at which CDP packets are sent (in sec) run Router(config)#cdp timer 90 Router(config)#cdp holdtime 240 Router(config)#^Z

CDP no cdp run config mode router.

no cdp enable cdp enable cdp

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Show cdp neighbor( sh cdp nei)

,CDPCiscorouter show cdp neighbor 2509router

Todd2509#sh cdp nei Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge, S - Switch, H - Host, I - IGMP, r - Repeater Device ID Local Intrfce Holdtme Capability Platform Port ID 1900Switch Eth 0 238 T S 1900 2 2500B Ser 0 138 R 2500 Ser 0 Todd2509# router2509router

1900router25002500B. 1900router2500BCDProuter2509..

9.5 show cdp neighbor 9.5 show cdp neighbor

Field

Device ID Local Interface CDP Holdtime router CDP Capabillity Capabillity code cdp neighborrouter, Platform ,Cisco 2509, Cisco 2511, Catalyst 5000,2509router2501 0 Port ID CDPmuticast

show cdp neighbor detail ( show cdp nei de).routerrouter

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Todd2509#sh cdp neighbor detail ------------------------- Device ID: 1900Switch Entry address(es): IP address: 0.0.0.0 Platform: cisco 1900, Capabilities: Trans-Bridge Switch Interface: Ethernet0, Port ID (outgoing port): 2 Holdtime : 166 sec Version : V9.00 ------------------------- Device ID: 2501B Entry address(es): IP address: 172.16.10.2 Platform: cisco 2500, Capabilities: Router Interface: Serial0, Port ID (outgoing port): Serial0 Holdtime : 154 sec Version : Cisco Internetwork Operating System Software IOS (tm) 3000 Software (IGS-J-L), Version 11.1(5), RELEASE SOFTWARE (fc1)Copyright (c) 1986-1996 by cisco Systems, Inc.Compiled Tue 05-Aug-03 11:48 by mkamson Todd2509#

hostnameIP Address

show cdp nei IOS version

IP

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show cdp entry* show cdp neighbor details.show cdp entry*

Todd2509#sh cdp entry * ------------------------- Device ID: 1900Switch Entry address(es): IP address: 0.0.0.0 Platform: cisco 1900, Capabilities: Trans-Bridge Switch Interface: Ethernet0, Port ID (outgoing port): 2 Holdtime : 223 sec Version : V9.00 ------------------------- Device ID: 2501B Entry address(es): IP address: 172.16.10.2 Platform: cisco 2500, Capabilities: Router Interface: Serial0, Port ID (outgoing port): Serial0 Holdtime : 151 sec Version : Cisco Internetwork Operating System Software IOS (tm) 3000 Software (IGS-J-L), Version 11.1(5), RELEASE SOFTWARE (fc1)Copyright (c) 1986-1996 by cisco Systems, Inc.Compiled Tue 05-Aug-03 11:48 by mkamson Todd2509#

show cdp traffic (traffic) cdp

cdp show cdp trafficrouter2509

Todd2509#sh cdp traffic CDP counters: Packets output: 13, Input: 8 Hdr syntax: 0, Chksum error: 0, Encaps failed: 0 No memory: 0, Invalid packet: 0, Fragmented: 0 Todd2509#

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router CDP

Interface show cdp interfaceCDP router interface Switch Port , CDP router(router) no cdp run CDP - no cdp Enableport show cdp interface CDP timer hold time

Todd2509#sh cdp interface Ethernet0 is up, line protocol is up Encapsulation ARPA Sending CDP packets every 60 seconds Holdtime is 180 seconds Serial0 is administratively down, line protocol is down Encapsulation HDLC Sending CDP packets every 60 seconds Holdtime is 180 seconds Serial1 is administratively down, line protocol is down Encapsulation HDLC Sending CDP packets every 60 seconds Holdtime is 180 seconds

CDProuter no cdp enable interface configuration mode Todd2509#config t Enter configuration commands, one per line. End with CNTL/Z. Router(config)#int s0 Router(config-if)#no cdp enable Router(config-if)#^Z

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show cdp interface Todd2509#sh cdp int Ethernet0 is up, line protocol is up Encapsulation ARPA Sending CDP packets every 60 seconds Holdtime is 180 seconds Serial1 is administratively down, line protocol is down Encapsulation HDLC Sending CDP packets every 60 seconds Holdtime is 180 seconds Todd2509#

serial0router enable cdp serial0

CDP

.... ,() . CDProuterCiscoCDPCisco..CDP ,CDP- .

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Telnet Telnet. TCP/IP router.Telnetrouter Telnet Command Prompt(DOS or Cisco) VTY router CDProuterTelnet run CDP

Telnetrouter prompt Todd2509#telnet 172.16.10.2 Trying 172.16.10.2 ... Open Password required, but none set [Connection to 172.16.10.2 closed by foreign host] Todd2509#

VTY

VTY no login (4) Telnet . Telnet

routerCiscoTelnet IP Address Command Prompt router Telnet

Todd2509#172.16.10.2 Trying 172.16.10.2 ... Open Password required, but none set [Connection to 172.16.10.2 closed by foreign host] Todd2509# VTYrouter

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router2509console Todd2509#172.16.10.2 Trying 172.16.10.2 ... Open User Access Verification Password: 2501B>

VTY user-mode enable-mode telnet router 2501B

2501B>en % No password set 2501B>

telnetting enable Privilage mode() enable-mode

enable secret password telnet telnet hostnames

IP

Telnetting Telnet router, exit .

router? ctrl+shift+6 x router Tood 2509

Todd2509#telnet 172.16.10.2 Trying 172.16.10.2 ... Open User Access Verification Password: 2501B>[Cntl+Shift+6, then X] Todd2509# ,Telnetted2501B User mode, Ctrl+Shift+6

X () Command Prompt router Todd2509

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telnet 1900 , enable mode password 15 telnet , tellneted 1900 Console Output

Todd2509#telnet 192.168.0.148 Trying 192.168.0.148 ... Open Catalyst 1900 Management Console Copyright (c) Cisco Systems, Inc. 1993-1999 All rights reserved. Enterprise Edition Software Ethernet Address: 00-B0-64-75-6B-C0 PCA Number: 73-3122-04 PCA Serial Number: FAB040131E2 Model Number: WS-C1912-A System Serial Number: FAB0401U0JQ Power Supply S/N: PHI033108SD PCB Serial Number: FAB040131E2,73-3122-04 ------------------------------------------------- 1 user(s) now active on Management Console. User Interface Menu [M] Menus [K] Command Line Enter Selection:

At this point, I pressed Ctrl+Shift+6, then X, which took me back to my Todd2509 router console:( Crtl+Shift+6 x Todd 2509 remote console) Todd2509#

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Telnet router Show session

Todd2509#sh sessions Conn Host Address Byte Idle Conn Name 1 172.16.10.2 172.16.10.2 0 0 172.16.10.2 * 2 192.168.0.148 192.168.0.148 0 0 192.168.0.148 Todd2509# (*)22.

Enter 2 Enter 2

Telnet VTY router Show users

Todd2509#sh users Line User Host(s) Idle Location * 0 con 0 172.16.10.2 00:07:52 192.168.0.148 00:07:18

Telnet Console VTY router Show users

Todd2509#sh users Line User Host(s) Idle Location * 0 con 0 172.16.10.2 00:07:52 192.168.0.148 00:07:18

,con local console.console2 ip address 2 , sh users router2501BrouterTood2509telnetted

2501B>sh users Line User Host(s) Idle Location 0 con 0 idle 9 * 2 vty 0

Console 12VTY *() Show user

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Telnet Telnet exitdisconnect Session exit

Todd2509#[Enter] and again [Enter] [Resuming connection 2 to 192.168.0.148 ... ] 1900Switch>exit [Connection to 192.168.0.148 closed by foreign host] Todd2509# 1900session,Enter 2 Session Session, disconnect Todd2509#disconnect ? The number of an active network connection WORD The name of an active network connection Todd2509#disconnect 1 Closing connection to 172.16.10.2 [confirm] Todd2509# Session number 1router2501B

Show Sessions SessionsTelnetrouter Show users

2501B#sh users Line User Host(s) Idle Location * 0 con 0 idle 0 1 aux 0 idle 0 2 vty 0 idle 0 172.16.10.1 VTY 0 IP Address 172.16.10.1 routerTodd2509

connection clear line #(#connection) 2501B#clear line 2 [confirm] [OK]

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userdisconnectshow users

2501B#sh users Line User Host(s) Idle Location 0 con 0 idle 0 1 aux 0 idle 1 2501B#

Hostname hostnameIP Address, hostname IP Address hostnameIP Adress1hostrouter2Domain Name System(DNS)host

host table Host table router hos table t ip host host_name tcp_port_number ip_address TCP23SessionTelnetTCP, 8 ip address host name host2router2501B

Todd2509#config t Enter configuration commands, one per line. End with CNTL/Z. Todd2509(config)#ip host ? WORD Name of host Todd2509(config)#ip host 2501B ? Default telnet port number A.B.C.D Host IP address (maximum of 8) Todd2509(config)#ip host 2501B 172.16.10.2 ? A.B.C.D Host IP address (maximum of 8) Todd2509(config)#ip host 2501B 172.16.10.2 Todd2509(config)#ip host 1900Switch 192.168.0.148 Todd2509(config)#^Z

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hostshow hosts

Todd2509#sh hosts Default domain is not set Name/address lookup uses domain service Name servers are 255.255.255.255 Host Flags Age Type Address(es) 2501B (perm, OK) 0 IP 172.16.10.2 1900Switch (perm, OK) 0 IP 192.168.0.148 Todd2509#

Perm Flag manually (Automatic) tempDNS

show hosts temporary ()DNS ip host

host .host namesrouter prompt router Telnet host name telnetCtrl+Shift+6 X Console router Todd2509

Todd2509#2501b Trying 2501B (172.16.10.2)... Open User Access Verification Password: 2501B> Todd2509#[Ctrl+Shift+6, then X] Todd2509#1900switch Trying 1900switch (192.168.0.148)... Open Catalyst 1900 Management Console Copyright (c) Cisco Systems, Inc. 1993-1999 All rights reserved. Enterprise Edition Software Ethernet Address: 00-B0-64-75-6B-C0 PCA Number: 73-3122-04 PCA Serial Number: FAB040131E2

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Model Number: WS-C1912-A System Serial Number: FAB0401U0JQ Power Supply S/N: PHI033108SD PCB Serial Number: FAB040131E2,73-3122-04 ------------------------------------------------- 1 user(s) now active on Management Console. User Interface Menu [M] Menus [K] Command Line Enter Selection:[Ctrl+Shift+6, then X] Todd2509#

host session telnet

Output Show Session Host name IP address Todd2509#sh sess Conn Host Address Byte Idle Conn Name 1 1900switch 192.168.0.148 0 0 switch * 2 2501b 172.16.10.2 0 0 2501b Todd2509#

hostname . on ip host

RouterA(config)#no ip host routerb methodhosthostrouterrouter,DNS

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DNS server host table DNS hostnames Cisco DNS , todd Cisco router prompt

Todd2509#todd Translating "todd"...domain server (255.255.255.255) % Unknown command or computer name, or unable to find computer address Todd2509#

. DNS.,2. 2. DNS lookup (DNS) ip domainlookuprouter global configuration mode DNS DNS name - ip domain-lookup (no ip domain-lookup) - 2 ip name-server ip address DNS IP Address 6 - ip domain-name . Domain name hostname DNSDomain name Doamin.com

Todd2509#config t Enter configuration commands, one per line. End with CNTL/Z. Todd2509(config)#ip domain-lookup Todd2509(config)#ip name-server ? A.B.C.D Domain server IP address (maximum of 6) Todd2509(config)#ip name-server 192.168.0.70 Todd2509(config)#ip domain-name lammle.com Todd2509(config)#^Z Todd2509#

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DNSDNShostname pingtelnet Todd2509#ping 2501b Translating "2501b"...domain server (192.168.0.70) [OK] Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 172.16.10.2, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 28/31/32 ms

router DNS Server Address

Dns ,Host Host table: Todd2509#sh hosts Default domain is lammle.com Name/address lookup uses domain service Name servers are 192.168.0.70 Host Flags Age Type Address(es) 2501b.lammle.com (temp, OK) 0 IP 172.16.10.2 1900switch (perm, OK) 0 IP 192.168.0.148 Todd2509#

temp , 1900 swith perm . host. ip domain-name lammle.com , ping 2501.lammle.com,.

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host table DNS server?

Karen CDP . Hewever,Karen ip telnet router .

Karen host table rounter , rounter DNS , hostname

hostnames router ! router blammo.

update , DNS server router static host table.

, host , router .

ping (Packet Internet Groper) traceroute

, protocols , ip . show ip route . show interfaced . ip rout interfaces 4.

ping , ping ip DNS

server. PING ping ?:

Todd2509#ping ?

WORD host name ping apollo Apollo echo appletalk Appletalk echo clns CLNS echo decnet DECnet echo

35

ip IP echo ipx Novell/IPX echo srb srb echo tag Tag encapsulated IP echo vines Vines echo xns XNS echo

ping ,, ping (packet)

Todd2509#ping todd2509 Translating "todd2509"...domain server (192.168.0.70)[OK] Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 192.168.0.121, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 32/32/32 ms Todd2509#

DNS server ping 32 ms(milliseconds).

ping user mode privileged mode

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traceroute

Traceroute ( Traceroute ) packet . traceroute protocol. traceroute ? :

Todd2509#traceroute ? WORD address host name appletalk AppleTalk Trace clns ISO CLNS Trace ip IP Trace ipx IPX Trace oldvines Vines Trace (Cisco) vines Vines Trace (Banyan)

trace hop hop

Todd2509#trace 2501b Type escape sequence to abort. Tracing the route to 2501b.lammle.com (172.16.10.2) 1 2501b.lammle.com (172.16.10.2) 16 msec * 16 msec Todd2509#

packet 1 hop . Tip . tracert windows . router. traceroute

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, cisco router router 9 Cisco Internetwork

router, rom,ram,nvram flash. boot router boots router file. register boots router files . register password recovery ..(back up) (restore) cisco ios image.(back up) (restore) router Cisco

telnet CDP . . hostname ping trace net work .

- register (setting). 0x2102 cisco router

router NVRAM boot . 0x2101 router boot ROM. x2142 router startupconfig NVRAM password recovery.

- (backup) ios image. privileged- mode fttp. file flash memory tftp (network) server.

- (restore)(upgrade) ios image. privileged- mode tftp. (restore)(upgrade) file tftp (network) server flash memory.

- back up ios image network server. network server . network server code image . .

- router.. running-config , startup-config

- configulation router. privileged-mode startup config reload router - CDP Cisco Discovery Protocol document network network .

- output show CDP neighbors. show CDP neighbors device ID ,local interface ,hold time ,capability ,platform , port ID()

- telnet router. . originating consol

38

telnet router switch. exit .. remote device router ctrl+alt+6 . x.

- telnet . show sessions router router

- static host table router . global configuration mode,ip , host , host_name, ip_address, static host table router . ip address host entry .

- host table router . host table show hosts. - ping host ID . ping IP address routers user mode privileged mode.

configuration mode. ping ip . 1.1.1.1 address 192.168.10.0, 192.168.10.255 192.168.10.256.( 3 IP Subnetting and Variable Length Subnet Masks (VLSMs), ip address )