Ccna Lab Manual

5/23/2018 Ccna Lab Manual

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CCNALab Guide


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Cisco IOS Introduction

General Reading:-

System Architecture

Like a computer, a router has a CPU that varies in performance and capabilities depending on the

router platform. Two examples of processors that Cisco uses are the Motorola 68030 and theOrion/R4600. The Cisco IOS software running in the router requires the CPU or processor to makerouting and bridging decisions, maintain routing tables, and other system management functions.The CPU must have access to data in memory to make decisions or to get instructions.

There are usually four types of memory on a Cisco router:

ROMROM is generally the memory on a chip or multiple chips. It is available on a router'sprocessor board. It is read-only, which means that data cannot be written to it. The initial softwarethat runs on a Cisco router is called the bootstrap software and is usually stored in ROM. Thebootstrap software is invoked when the router boots up.

FlashFlash memory is located on a processor board SIMM but can be expanded using PCMCIA

(removable) cards. Flash memory is most commonly used to store one or more Cisco IOS softwareimages. Configuration files or system information can also be copied to Flash. On some high-endsystems, Flash memory is also used to hold bootstrap software.

RAMRAM is very fast memory that loses its information when the system is restarted. It is used inPCs to store running applications and data. On a router, RAM is used to hold IOS system tables andbuffers. RAM memory is basically used for all system operational storage requirements.

NVRAMOn the router, NVRAM is used to store the startup configuration. This is the configurationfile that IOS reads when the router boots up. It is extremely fast memory and is persistent acrossreboots.

Although CPU and memory are required components to run IOS, a router must also have various

interfaces to allow packet forwarding. Interfaces are input and output connections to the router thatcarries data that needs to be routed or switched. The most common types of interfaces are Ethernetand serial. Similar to the driver software on a computer with parallel ports and USB ports, IOS hasdevice drivers to support these various interface types. All Cisco routers have a console port thatprovides an EIA/TIA-232 asynchronous serial connection. The console port can be connected to acomputer's serial connection to gain terminal access to the router. Most routers also have anauxiliary port that is very similar to the console port, but is typically used for modem connection forremote router management.

Following Output shows the console output of a new Cisco 3640 router that has just been started.Notice the processor, interface, and memory information that is listed.

System Bootstrap, Version 11.1(20)AA2, EARLY DEPLOYMENT RELEASE SOFTWARE (fc1)Copyright (c) 1999 by Cisco Systems, Inc.C3600 processor with 98304 Kbytes of main memoryMain memory is configured to 64 bit mode with parity disabled

program load complete, entry point: 0x80008000, size: 0xa8d168Self decompressing the image :##################################################################################################################### [OK]

Restricted Rights Legend


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Use, duplication, or disclosure by the Government is

subject to restrictions as set forth in subparagraph

(c) of the Commercial Computer Software - Restricted

Rights clause at FAR sec. 52.227-19 and subparagraph

(c) (1) (ii) of the Rights in Technical Data and Computer

Software clause at DFARS sec. 252.227-7013.

Cisco Systems, Inc.

170 West Tasman Drive

San Jose, California 95134-1706

Cisco Internetwork Operating System Software

IOS (tm) 3600 Software (C3640-IS-M), Version 12.2(10), RELEASE SOFTWARE (fc2)

Copyright (c) 1986-2002 by Cisco Systems, Inc.

Compiled Mon 06-May-02 23:23 by pwade

Image text-base: 0x60008930, data-base: 0x610D2000

cisco 3640 (R4700) processor (revision 0x00) with 94208K/4096K bytes of memory.

Processor board ID 17746964

R4700 CPU at 100Mhz, Implementation 33, Rev 1.0

Bridging software.

X.25 software, Version 3.0.0.

SuperLAT software (copyright 1990 by Meridian Technology Corp).

5 Ethernet/IEEE 802.3 interface(s)

1 Serial network interface(s)

DRAM configuration is 64 bits wide with parity disabled.

125K bytes of non-volatile configuration memory.

8192K bytes of processor board System flash (Read/Write)

16384K bytes of processor board PCMCIA Slot0 flash (Read/Write)

--- System Configuration Dialog ---

Would you like to enter the initial configuration dialog? [yes/no]:

When a new router is first started, IOS runs an autoinstall process wherein the user is prompted to

answer a few questions. IOS then configures the system based on the input provided. After initialsetup, the configuration is most commonly modified using the command-line interface (CLI). Otherways of configuring the router include HTTP and network management applications

Cisco IOS has three command modes, each with access to different command sets:


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User modeThis is the first mode a user has access to after logging into the router. The usermode can be identified by the > prompt following the router name. This mode allows the user toexecute only the basic commands, such as those that show the system's status. The system cannotbe configured or restarted from this mode.

Router>

Privileged modeThis mode allows users to view the system configuration, restart the system,

and enter configuration mode. It also allows all the commands that are available in user mode.Privileged mode can be identified by the # prompt following the router name. The user mode enablecommand tells IOS that the user wants to enter privileged mode. If an enable password or enablesecret password has been set, the user needs to enter the correct password or secret to be grantedaccess to privileged mode. An enable secret password uses stronger encryption when it is stored inthe configuration and, therefore, is safer. Privileged mode allows the user to do anything on therouter, so it should be used with caution. To exit privileged mode, the user executes the disablecommand.

Router#

Configuration modeThis mode allows users to modify the running system configuration. To enterconfiguration mode, enter the command configure terminal from privileged mode. Configurationmode has various submodes, starting with global configuration mode, which can be identified by the(config)# prompt following the router name. As the configuration mode submodes changedepending on what is being configured, the words inside the parentheses change. For example,when you enter interface configuration submode, the prompt changes to (config-if)# following therouter name. To exit configuration mode, the user can enter end or press Ctrl-Z.

Router(config)#

Terminal Server

Now days it is very difficult to use console cable and access multiple devices as routers andswitched which we configure are placed in datacenter, to overcome this problem we use terminalserver. This is a single point of management device.

A terminal or comm server commonly provides out-of-band access for multiple devices. A terminalserver is a router with multiple, low speed, asynchronous ports that are connected to other serial

devices, for example, modems or console ports on routers or switches.

The terminal server allows you to use a single point to access the console ports of many devices. Aterminal server eliminates the need to configure backup scenarios like modems on auxiliary ports forevery device. You can also configure a single modem on the auxiliary port of the terminal server, toprovide dial-up service to the other devices when network connectivity fails.

Below is the pictorial scenario which shows the working of terminal server


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Task 1Telnet to CCNA Terminal Server at IP address 172.16.50.88

Solution:

In Linux Base system such as Ubuntu go to applications then accessories and clickon terminal and type telnet 172.16.50.88

For Windows machine go to run and type telnet 172.16.50.88

Task 2After you telnet into terminal server it will ask you for username and password,

use username:student and password:student

Solution:

telnet 172.16.50.88

+--------------------------------------------------------------------+

| Following commands are available for use at privilege 0 |

| 1).Show Host |

| 2).Show Sessions |

| 3).Show Users |

| 4).Clear Line |

| 5).Disconnect |

| |

| Following CCNA Racks Can be Accessed From This Terminal :- |

| 1).CCNA-Rack1 |

| 2).CCNA-Rack2 |


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| 3).CCNA-Rack3 |

| 4).CCNA-Rack4 |

| 5).CCNA-Rack5 |

| 6).CCNA-Rack6 |

| 7).CCNA-Rack7 |

| 8).CCNA-Rack8 |

| 9).CCNA-Rack9 |

| 10).CCNA-Rack10 |

+--------------------------------------------------------------------+

********************************************************************

* WELCOME TO ACIT Bangalore *

* YOU ARE CONNECTED TO CCNA-TERMINAL 88 *

********************************************************************

User Access Verification

Username: student

Password:

CCNA_Term#

Task 3use show host commands to see the available racks.

Solution:

CCNA_Term#show host

Default domain is not set

Name/address lookup uses static mappings

Codes: UN - unknown, EX - expired, OK - OK, ?? - revalidate

temp - temporary, perm - permanent

NA - Not Applicable None - Not defined

Host Port Flags Age Type Address(es)

Rack1-R1 1026 (perm, OK) 64 IP 128.0.0.2

Rack1-R3 1028 (perm, OK) 84 IP 128.0.0.2

Rack1-SW1 1029 (perm, OK) 84 IP 128.0.0.2

Rack1-SW2 1030 (perm, OK) 84 IP 128.0.0.2

..

Task 4Now access device rack1-r1

Solution:


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CCNA_Term#rack1-r1

Translating "rack1-r1"

Trying Rack1-R1 (128.0.0.2, 1026)... Open

% Please answer 'yes' or 'no'.

Would you like to enter the initial configuration dialog? [yes/no]:no

Press RETURN to get started!

Router>

(Note:-At this point we are in device R1 of rack1)

Task 5Lock the session of R1 and come back to terminal server by pressingCTRL+SHIFT+6 X

Solution:

Router>

CCNA_Term#

Task 6Now open rack1-r2, rack1-r3, rack1-sw1 and rack1-sw2

Solution:

CCNA_Term#rack1-r2




Router>

CCNA_Term#rack1-r3




Router>

CCNA_Term#rack1-sw1

Translating "rack1-sw1"

Trying Rack1-SW1 (128.0.0.2, 1029)... Open


switch>

CCNA_Term#rack1-sw2

Translating "rack1-sw2"

Trying Rack1-SW2 (128.0.0.2, 1030)... Open


switch>

Task 7Go back to Terminal Server and check the sessions which you have opened bypressing CTRL+SHIFT+6 X


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Solution:

CCNA_Term#show sessions

Conn Host Address Byte Idle Conn Name

1 rack3-r1 128.0.0.2 162 8 rack3-r1

2 rack3-r2 128.0.0.2 0 0 rack3-r2

3 rack3-r3 128.0.0.2 0 0 rack3-r34 rack3-sw1 128.0.0.2 39 0 rack3-sw1

* 5 rack3-sw2 128.0.0.2 0 0 rack3-sw2

(Note:-In above output you can see that we have opened 5 session. Automatically connectionnumbers are assigned to every session. So next time if you want to access R1 then we dont haveto press rack1-r1 again it can be simply accessed by pressing its current connection number i.e. 1.The Star before 5 shows the current active connection)

Task 8on R1,R2,R3,SW1,SW2 Assign hostname R1,R2,R3,SW1,SW2 respectively

Solution:

CCNA_Term#1

[Resuming connection 1 to rack1-r1 ... ]

Router>enable

Router#config t

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#hostname R1

R1(config)#

CCNA_Term#2


Router>enable

Router#config t



R2(config)#

CCNA_Term#3


Router>enable

Router#config t



R3(config)#


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CCNA_Term#4

[Resuming connection 4 to rack1-SW1 ... ]

Switch>enable

Switch#config t


Switch(config)#hostname SW1

SW1(config)#

CCNA_Term#5

[Resuming connection 5 to rack1-SW2 ... ]

Switch>enable

Switch#config t


Switch(config)#hostname SW2

SW2(config)#

Task 9Go to R1 and Check the available interfaces

Solution:

On R1:

R1#show ip interface brief

Interface IP-Address OK? Method Status ProtocolEthernet0/0 unassigned YES unset administratively down down

Ethernet0/1 unassigned YES unset administratively down down



Serial1/0 unassigned YES unset administratively down down




(Note:-Above are the list of interfaces available on router R1 but it may vary as device to device)


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Task 9On R1 assign IP address 10.0.0.1 and use classful subnetmask to interface

Ethernet 0/0 and verify your configuration.

Solution:

On R1:

R1#

R1#configure terminal


R1(config)#interface ethernet 0/0

R1(config-if)#ip address 10.0.0.1 255.0.0.0

R1(config-if)#no shutdown

R1(config-if)#exit

*Jul 1 00:37:53.867: %LINK-3-UPDOWN: Interface Ethernet0/0, changed state to

up

*Jul 1 00:37:54.871: %LINEPROTO-5-UPDOWN: Line protocol on InterfaceEthernet0/0, changed state to up

R1(config)#exit

R1#

(Note:- We Can See that no shutdown command has been issued to start the interface. After

issuing the command we can see that 2 log massages are appeared on the console, stating that link

and line-protocol changed to up.)

Verification:

On R1:

R1#


Interface IP-Address OK? Method Status Protocol

Ethernet0/0 10.0.0.1 YES manual up up

Ethernet0/1 unassigned YES unset administratively down downEthernet0/2 unassigned YES unset administratively down down


Serial1/0 unassigned YES manual administratively down down


...

(Note:-In verification we can see that interface status and line protocol of interface Ethernet 0/0 is

UP, also we can see that IP address which we assigned Is there, we should always consider a

important note that every UP interface of router which has ip address is assigned defines one whole

network, in this case interface Ethernet 0/0 defines the network 10.0.0.0 255.0.0.0, it can be verified

with show ip route command, therefore we cannot give any ip from this network to any other

interface of the this router.)


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R1#show ip route

Codes: L - local, C - connected, S - static, R - RIP, M - mobile,

B BGP , D - EIGRP, EX - EIGRP external, O OSPF

IA - OSPF inter area , N1 - OSPF NSSA external type 1,

N2 - OSPF NSSA external type 2 , E1 - OSPF external type 1,

E2 - OSPF external type 2 , i - IS-IS, su - IS-IS summary,

L1 - IS-IS level-1, L2 - IS-IS level-2 ,

ia - IS-IS inter area, * - candidate default,

U - per-user static route , o - ODR,

P - periodic downloaded static route, + - replicated route

Gateway of last resort is not set

10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks

C 10.0.0.0/8 is directly connected, Ethernet0/0

L 10.0.0.1/32 is directly connected, Ethernet0/0

(Note:-above output is called routing table of the router. In this table router keeps the entries of

networks know to him, We can see C as legend before network entry of 10.0.0.0/8 it shows that it

is directly connected on Ethernet 0/0, L entry shows the local ip address of the network 10.0.0.0/8,

which we assigned to the interface int this task.)

Task 10Check the current configuration of the router with show running-config command

and save the configuration.

Verification:

R1#show running-config

Building configuration...

Current configuration : 1161 bytes

!

version 12.4

service timestamps debug datetime msec

service timestamps log datetime msec

no service password-encryption

!

hostname R1

!

boot-start-marker

boot-end-marker

!

!


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no aaa new-model

clock timezone IST 5 30

mmi polling-interval 60

no mmi auto-configure

no mmi pvc

mmi snmp-timeout 180

ip source-route!

!

!

!

ip cef

no ipv6 traffic interface-statistics

no ipv6 cef

!

multilink bundle-name authenticated

!

!

!

redundancy

!

!

!

interface Ethernet0/0

ip address 10.0.0.1 255.0.0.0

!


no ip address

shutdown

!


no ip address

shutdown

!


no ip address

shutdown

!

interface Serial1/0

no ip address

shutdown

serial restart-delay 0

!

interface Serial1/1


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no ip address

shutdown


!

interface Serial1/2

no ip address

shutdownserial restart-delay 0

!

interface Serial1/3

no ip address

shutdown


!

ip forward-protocol nd

!

!

no ip http server

no ip http secure-server

!

!

control-plane

!

!

line con 0

logging synchronous

line aux 0

line vty 0 4

login

!

exception data-corruption buffer truncate

end

R1#

R1#write

Building configuration...

[OK]

R1#

Task 11Erase All the Devices and Reload

Solution:

R1#write erase

Erasing the nvram filesystem will remove all configuration files! Continue?[confirm]


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[OK]

Erase of nvram: complete

R1#

*Jul 1 01:09:36.006: %SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram

R1#reload

Proceed with reload? [confirm]

*Jul 1 01:09:39.958: %SYS-5-RELOAD: Reload requested by console. ReloadReason: Reload Command.

R2#write erase

Erasing the nvram filesystem will remove all configuration files! Continue?[confirm]

[OK]

Erase of nvram: complete

R2#

*Jul 1 01:09:36.006: %SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram

R2#reload

Proceed with reload? [confirm]

*Jul 1 01:09:39.958: %SYS-5-RELOAD: Reload requested by console. ReloadReason: Reload Command.

...


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IP Routing

Need of Routing:-

Routing is the process of moving data from one network to another by forwarding packets viagateways. With IP based networks, the routing decision is based on the destination address in theIP packet's header. Routing is the process of moving a packet of data from one network to another

network based on the destination IP address. The Internet uses routing to move data from yourcomputer, across several networks, to reach a final destination, like a website. Specializedcomputer devices that perform this routing function are referred to as routers. Routers use theinformation contained in a route to make decisions about which network interface to forward apacket through in order to reach the destination address in the packet. Routers maintain a list ofroutes which is often referred to as a routing table.

Routers look up routes in the routing table to figure out how to move data from one network toanother network. Routes are simply the signposts that tell a router which network interface toforward a packet through in order

toreach the packet's intended destination

Types of Routing

There are two basic kinds of routes: static or dynamic.

1. Static Routes

Routes can be entered into a router by a person who administrates the network (the networkadministrator). Since these routes are entered by the administrator, and these routes don't changeuntil the administrator changes them, they are referred to as staticroutes.

2. Default Routes

A default route is also referred to as the 'route of last resort'. This is the route a router uses when allother routes have been examined and none seem to be the right route to use.

3.Dynamic Routes

If the routes are learned on-the-fly from other routers, it is called a dynamically-learned route, or adynamic routefor short. Dynamic routes are learned from routing protocols.

4.Routing Protocol

A routing protocol is a standardized process by which routers learn and communicate connectivity

information, called routes, each of which which describes how to reach a destination host and

network. Routers that wish to exchange routing information must use the same routing protocol to

communicate routing information.


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Routing is the process of learning all the paths through the network (routes) and using routes toforward data from one network to another. Aprotocolis a standardized way to perform a task. So, arouting protocol would be a standardized way of learning routes and moving data from one networkto another.

Routing protocols are used by routers to dynamically learn all paths through a set of networks andforward data between the networks. Routers are specialized computer devices designed to performrouting.

5.Examples of Routing Protocols

EIGRP OSPF RIP, RIP II IS-IS BGP


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Static Routing Configuration

Task 1Assign Hostnames to Router1, Router2, Router3 R1, R2, R3 respectively.

Solution:

On Router1 :

Router>enable

Router#config

Router#configure terminal


R1(config)#

On Router2 :

Router>enable

Router#config



R2(config)#

On Router3 :

Router>enable


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Router#config



R3(config)#

Task 2 Assign IP address 12.0.0.1 and subnet mask of 255.0.0.0 to interface Serial 1/0 andIP address 10.0.0.1 255.0.0.0 to interface Ethernet0/0 on R1. After you complete yourconfiguration verify it.

Solution:

On R1 :

R1(config)#interface serial 1/0



R1(config-if)#exit

R1(config-if)#int ethernet0/0



R1(config-if)#exit

R1(config)#exit

Verification :







Serial1/0 12.0.0.1 YES manual up up




Task 3 Similarly assign ip address to R2 and R3 as per the diagram.


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Solution:

On R2 :



R2(config-if)#clock rate 64000


R2(config-if)#exit



R2(config-if)#clock rate 64000





R2(config-if)#exit

R2(config)#exit

R2#

Verification:

R2#show ip int brief










On R3 :




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R3(config-if)#exit




R3(config-if)#exit

R3(config)#exit

R3#

Task 4Check Connectivity Between Directly Connected Interfaces.

Verification:

On R1:

R1#ping 12.0.0.2

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 12.0.0.2, timeout is 2 seconds:

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 8/8/12 ms

On R2 :

R2#

R2#ping 12.0.0.1



!!!!!


R2#ping 23.0.0.3



!!!!!


R2#

On R3 :


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R3#

R3#ping 23.0.0.2



!!!!!


R3#

Task 5 Save your configuration

Solution:

On R1:

R1#write

On R2:

R2#write

On R3:

R3#write

Task 6 Configure a static route from R1 so that it can reach networks 23.0.0.0/8, 20.0.0.0/830.0.0.0/8

Solution:

On R1:

R1#

R1#config terminal

R1(config)#ip route 20.0.0.0 255.0.0.0 12.0.0.2

R1(config)#ip route 23.0.0.0 255.0.0.0 12.0.0.2

R1(config)#ip route 30.0.0.0 255.0.0.0 12.0.0.2

Verification:

R1#

R1#show ip route

Codes: L local, C connected, S static, R RIP, M mobile,

B BGP, D EIGRP, EX EIGRP external, O OSPF,

IA OSPF inter area, N1 OSPF NSSA external type 1,

N2 OSPF NSSA external type 2 E1 OSPF external type 1,


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E2 OSPF external type 2, i IS-IS, su IS-IS summary,

L1 IS-IS level-1, L2 IS-IS level-2, ia IS-IS inter area

* - candidate default, U per-user static route o ODR,

P periodic downloaded static route, + - replicated route






C 12.0.0.0/8 is directly connected, Serial1/0

L 12.0.0.1/32 is directly connected, Serial1/0

S 20.0.0.0/8 [1/0] via 12.0.0.2

S 23.0.0.0/8 [1/0] via 12.0.0.2

S 30.0.0.0/8 [1/0] via 12.0.0.2

R1#

Task 7 Configure R2 so that it gets reach ability to networks 10.0.0.0/8, and 30.0.0.0/8 do not specify

next hop address to achieve this task

On R2 :

R2#


R2(config)#ip route 10.0.0.0 255.0.0.0 serial 1/0

R2(config)#ip route 30.0.0.0 255.0.0.0 serial 1/1

R2(config)#exit

R2#

Verification:

R2#

R2#show ip route



IA OSPF inter area, N1 OSPF NSSA external type 1,

N2OSPF NSSA external type 2, E1

OSPF external type 1,

E2 OSPF external type 2, i IS-IS, su IS-IS summary,

L1 IS-IS level-1, L2 IS-IS level-2, ia IS-IS inter area,


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* - candidate default, U per-user static route

o ODR, P periodic downloaded static route, + - replicated

route


S 10.0.0.0/8 is directly connected, Serial1/0










S 30.0.0.0/8 is directly connected, Serial1/1

R2#

Task 8: Configure R3 in such a manner that it gets rechability to all other networks in single static

route. Do not configure any more specific static routes to achieve this task.

On R3 :

R3#


R3(config)#ip route 0.0.0.0 0.0.0.0 23.0.0.2

R3(config)#exit

R3#

Verification :

R3#

R3#show ip route



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IA OSPF inter area N1 OSPF NSSA external type 1,

N2 OSPF NSSA external type 2 E1 OSPF external type 1,

E2 OSPF external type 2 i IS-IS, su IS-IS summary,

L1 IS-IS level-1, L2 IS-IS level-2

ia IS-IS inter area, * - candidate default,

U per-user static route

o ODR, P periodic downloaded static route, + - replicated route

Gateway of last resort is 23.0.0.2 to network 0.0.0.0

S* 0.0.0.0/0 [1/0] via 23.0.0.2




R3#

Task 9 : Ping 30.0.0.3 from R1,

Ping 10.0.0.1 and 30.0.0.3 for R2

Ping 10.0.0.1 from R3 to test end to end reachability.

R1#

R1#ping 30.0.0.3



!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 16/18/24ms

R1#

R2#

R2#ping 10.0.0.1



!!!!!


R2#

R2#ping 30.0.0.3



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!!!!!


R2#

R3#

R3#ping 10.0.0.1



!!!!!


R3#

Explanation:-

As we see from above output that we have got the full reachabltiy.

On R1 we have give destination network i.e 20.0.0.0,23.0.0.0 and 30.0.0.0 and their respectivesubnet masks and in the last part we gave the next hop address that is router to whom packetshould be routed.

Here the ip route format is ip route

ip route 20.0.0.0 255.0.0.0 12.0.0.2

ip route 23.0.0.0 255.0.0.0 12.0.0.2

ip route 30.0.0.0 255.0.0.0 12.0.0.2

on R2 we have been instructed not to give next hop address so we can here give outgoing interface

ip route 10.0.0.0 255.0.0.0 serial1/0

ip route 30.0.0.0 255.0.0.0 serial1/1

On R3 we have instructed not to use any specific routes so here we are using special static routewhich is also called as default route. That is if router does not get any specific network in his routingtable. It is going to use the default route to route the packet.


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ip route 0.0.0.0 0.0.0.0 23.0.0.2

RIPv2

RIPv2 was first described in RFC 1388 and RFC 1723 (1994); the current RFC is 2453, written inNovember 1998. Although current environments use advanced routing protocols such as OSPF andEIGRP, there still are networks using RIP. The need to use VLSMs and other requirementsprompted the definition of RIPv2.

RIPv2 improves upon RIPv1 with the ability to use VLSM, with support for route authentication, andwith multicasting of route updates. RIPv2 supports CIDR. It still sends updates every 30 secondsand retains the 15-hop limit; it also uses triggered updates. RIPv2 still uses UDP port 520; the RIPprocess is responsible for checking the version number. It retains the loop-prevention strategies ofpoison reverse and counting to infinity. On Cisco routers, RIPv2 has the same administrativedistance as RIPv1, which is 120. Finally, RIPv2 uses the IP address 224.0.0.9 when multicastingroute updates to other RIP routers. As in RIPv1, RIPv2 will, by default, summarize IP networks atnetwork boundaries. You can disable auto-summarization if required.

You can use RIPv2 in small networks where VLSM is required. It also works at the edge of largernetworks.

RIPv2 Forwarding Information Base

RIPv2 maintains a routing table database as in Version 1. The difference is that it also keeps thesubnet mask information. The following list repeats the table information of RIPv1:


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IP addressIP address of the destination host or network, with subnet mask GatewayThe first gateway along the path to the destination InterfaceThe physical network that must be used to reach the destination MetricA number indicating the number of hops to the destination TimerThe amount of time since the route entry was last updated

RIPv2 Design

Things to remember in designing a network with RIPv2 include that it supports VLSM withinnetworks and CIDR for network summarization across adjacent networks. RIPv2 allows for thesummarization of routes in a hierarchical network. RIPv2 is still limited to 16 hops; therefore, thenetwork diameter cannot exceed this limit. RIPv2 multicasts its routing table every 30 secondsto the multicast IP address 224.0.0.9. RIPv2 is usually limited to accessing networks where it caninteroperate with servers running routedor with non-Cisco routers. RIPv2 also appears at the edgeof larger internetworks. RIPv2 further provides for route authentication.

Split Horizon:

In this example, network node A routes packets to node B in order to reach node C. The linksbetween the nodes are distinct point-to-point links.

According to the split-horizon rule, nodeAdoes not advertise its route for C (namelyA to B to C)back to B. On the surface, this seems redundant since Bwill never route via node Abecause theroute costs more than the direct route from Bto C. However, if the link between Band Cgoes down,and Bhad received a route fromA, Bcould end up using that route via A.Awould send the packetright back to B, creating a loop. With the split-horizon rule in place, this particular loop scenariocannot happen, improving convergence time in complex, highly-redundant environments

Poison Reverse:

Split-horizon routing with poison reverse is a variant of split-horizon route advertising in which arouter actively advertises routes as unreachable over the interface over which they were learned.The effect of such an announcement is to immediately remove most looping routes before they canpropagate through the network.

The main disadvantage of poison reverse is that it can significantly increase the size of routingannouncements in certain fairly common network topologies.

RIPv2 Summary

The characteristics of RIPv2 follow:

Distance-vector protocol. Uses UDP port 520. Classless protocol (support for CIDR).
http://en.wikipedia.org/wiki/File:A-B-C.svg


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Supports VLSMs. Metric is router hop count. Maximum hop count is 15; infinite (unreachable) routes have a metric of 16. Periodic route updates sent every 30 seconds to multicast address 224.0.0.9. 25 routes per RIP message (24 if you use authentication). Supports authentication. Implements split horizon with poison reverse. Implements triggered updates.

Subnet mask included in route entry. Administrative distance for RIPv2 is 120. Used in small, flat networks or at the edge of larger networks.

RIP Configuration

Load IP Routing initials prior to starting

Task 1 Configure RIPv2 on R1 advertise its all network into RIP

Solution:

On R1:

R1#


R1(config)#router rip

R1(config-router)#version 2

R1(config-router)#network 10.0.0.0


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R1(config-router)#exit

R1(config)#exit

R1#

Verification:

On R1:

R1#

R1#show ip protocols

*** IP Routing is NSF aware ***

Routing Protocol is "rip"

Outgoing update filter list for all interfaces is not set

Incoming update filter list for all interfaces is not set

Sending updates every 30 seconds, next due in 27 secondsInvalid after 180 seconds, hold down 180, flushed after 240

Redistributing: rip

Default version control: send version 2, receive version 2

Interface Send Recv Triggered RIP Key-chain

Ethernet0/0 2 2

Serial1/0 2 2

Automatic network summarization is in effect

Maximum path: 4

Routing for Networks:

10.0.0.0

12.0.0.0

Routing Information Sources:

Gateway Distance Last Update

Distance: (default is 120)

R1#

Task 2 From above output we can see that R1 is doing auto-summarization so disable auto-summarization on R1


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Solution:

On R1:

R1#



R1(config-router)#no auto-summary


R1(config)#exit

R1#

Verification:

R1#






Sending updates every 30 seconds, next due in 0 secondsInvalid after 180 seconds, hold down 180, flushed after 240

Redistributing: rip



Ethernet0/0 2 2

Serial1/0 2 2

Automatic network summarization is not in effect

Maximum path: 4


10.0.0.0

12.0.0.0




R1#

Task 3configure RIP v2 on R2 and R3 advertise all the networks and disable auto-

summarization.


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Solution:

On R2:

R2#

R2#config terminal








R2(config)#exit

R2#

On R3:

R3#








R3(config)#exit

R3#

Task 4 Verify Routing tables of all 3 routers and test end-to-end connectivity.

Verification:

R1#show ip route


B BGP D - EIGRP, EX - EIGRP external, O - OSPF,

IA - OSPF inter area N1 - OSPF NSSA external type 1,


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N2 - OSPF NSSA external type 2, E1 - OSPF external type 1,

E2 - OSPF external type 2 i - IS-IS, su - IS-IS summary,

L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area,

* - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route,

+ - replicated route








20.0.0.0/24 is subnetted, 1 subnets

R 20.0.0.0 [120/1] via 12.0.0.2, 00:00:24, Serial1/0


R 23.0.0.0 [120/1] via 12.0.0.2, 00:00:24, Serial1/0


R 30.0.0.0 [120/2] via 12.0.0.2, 00:00:24, Serial1/0

R1#

R1#ping 23.0.0.2



!!!!!


R1#ping 20.0.0.2



!!!!!


R1#ping 30.0.0.3



!!!!!



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R1#

On R2:

R2#

R2#show ip route


B - BGP, D - EIGRP, EX - EIGRP external, O - OSPF,


N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1,

L2 - IS-IS level-2 , ia - IS-IS inter area,


o - ODR, P - periodic downloaded static route,+ - replicated route



R 10.0.0.0 [120/1] via 12.0.0.1, 00:00:14, Serial1/0











R 30.0.0.0 [120/1] via 23.0.0.3, 00:00:27, Serial1/1

R2#

R2#

R2#ping 10.0.0.1



!!!!!


R2#ping 30.0.0.3


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!!!!!


R2#

On R3:

R3#

R3#show ip route


B BGP, D - EIGRP, EX - EIGRP external, O - OSPF,

IA - OSPF inter area, N1 - OSPF NSSA external type 1,


E2 - OSPF external type 2, i - IS-IS, su - IS-IS summary,

L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area

, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route, + - replicated route



R 10.0.0.0 [120/2] via 23.0.0.2, 00:00:06, Serial1/0


R 12.0.0.0 [120/1] via 23.0.0.2, 00:00:06, Serial1/0


R 20.0.0.0 [120/1] via 23.0.0.2, 00:00:06, Serial1/0







R3#

R3#

R3#ping 12.0.0.1



!!!!!


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R3#ping 20.0.0.2



!!!!!


R3#ping 10.0.0.1



!!!!!


R3#

Task 5Configure all three routers in such way that they send updates through only required

interfaces

Solution:

On R1:

R1#config terminal


R1(config-router)#passive-interface ethernet 0/0


R1(config)#exit

R1#

On R2:

R2#config terminal




R2(config)#exit

R2#

On R3:


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R3#config terminal




R3(config)#exit

R3

Verification:

R1#






Sending updates every 30 seconds, next due in 2 seconds

Invalid after 180 seconds, hold down 180, flushed after 240

Redistributing: rip



Serial1/0 2 2Automatic network summarization is not in effect

Maximum path: 4


10.0.0.0

12.0.0.0

Passive Interface(s):

Ethernet0/0



12.0.0.2 120 00:00:01


Explanation:

Task 1 is asking us to configure RIP version 2 on all the interfaces. In the router rip sub

configuration we have to advertise our interfaces with network command. We can only declare

networks in their classfull boundaries. Version 2 is to be specified as default behavior is send

version 1 updates and receive both version 1 and version 2 updates.

This configuration can be checked in show ip protocols


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In configuration of task 2 we can see that by default RIP will always do auto-summarization. To

disable the auto-summarization we can give no auto-summary under RIP routing process.

Task 5 is asking us to send RIPv2 updates only out of required interface. Always remember that

RIPv2 does support classless network advertisement but we can only publish classfull networks in

RIPv2. By default all the routing protocols except BGP, Send hello packets and advertise the

networks, which we have defined by network command. In RIPv2 if we make a passive interface

then that interface is advertised but it does not send any updates. But the limitation in RIPv2 is this

interface can still receive RIP updates.

EIGRPImplementing EIGRP

EIGRP is an advanced distance vector routing protocol developed by Cisco. EIGRP is suited formany different topologies and media. In a well-designed network, EIGRP scales well and providesextremely quick convergence times with minimal overhead. EIGRP is a popular choice for a routingprotocol on Cisco devices.

Introducing EIGRP

EIGRP is a Cisco-proprietary routing protocol that combines the advantages of link-state anddistance vector routing protocols. EIGRP is an advanced distance vector or hybrid routing protocolthat includes the following features:

Rapid Convergence


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EIGRP uses the Diffusing Update Algorithm (DUAL) to achieve rapid convergence. A router thatuses EIGRP stores all available backup routes for destinations so that it can quickly adapt toalternate routes. If no appropriate route or backup route exists in the local routing table, EIGRPqueries its neighbors to discover an alternate route.

Reduced bandwidth usage

EIGRP does not make periodic updates. Instead, it sends partial updates when the path or the

metric changes for that route. When path information changes, DUAL sends an update about onlythat link rather than about the entire table.

Multiple network layer support

EIGRP supports AppleTalk, IP version 4 (IPv4), IP version 6 (IPv6), and Novell Internetwork PacketExchange (IPX), which use protocol-dependent modules (PDM). PDMs are responsible for protocolrequirements that are specific to the network layer.

Classless routing

Because EIGRP is a classless routing protocol, it advertises a routing mask for each destinationnetwork. The routing mask feature enables EIGRP to support discontiguous subnetworks andvariable-length subnet masks (VLSM).

Less overhead

EIGRP uses multicast and unicast rather than broadcast. As a result, end stations are unaffectedby routing updates and requests for topology information.

Load balancing

EIGRP supports unequal metric load balancing, which allows administrators to better distribute

traffic flow in their networks.

Easy summarization

EIGRP enables administrators to create summary routes anywhere within the network rather thanrely on the traditional distance vector approach of performing classful route summarization only atmajor network boundaries.

Each EIGRP router maintains a neighbor table. This table includes a list of directly connectedEIGRP routers that have an adjacency with this router.

Each EIGRP router maintains a topology table for each routed protocol configuration. The topologytable includes route entries for every destination that the router learns. EIGRP chooses the bestroutes to a destination from the topology table and places these routes in the routing table.

In EIGRP, the best route is called a successor route while a backup route is called the feasiblesuccessor. To determine the best route (successor) and the backup route (feasible successor) to adestination, EIGRP uses the following two parameters:

Advertised distance

The EIGRP metric for an EIGRP neighbor to reach a particular network


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Feasible distance

The advertised distance for a particular network learned from an EIGRP neighbor plus the EIGRPmetric to reach that neighbor

A router compares all feasible distances to reach a specific network and then selects the lowestfeasible distance and places it in the routing table. The feasible distance for the chosen routebecomes the EIGRP routing metric to reach that network in the routing table.

The EIGRP topology database contains all the routes that are known to each EIGRP neighbor.Routers A and B send their routing tables to Router C, whose table is displayed in Both Routers Aand B have pathways to network 10.1.1.0/24, as well as to other networks that are not shown

.

Configuring and Verifying EIGRP

Use the router eigrp and network commands to create an EIGRP routing process. Note thatEIGRP requires an autonomous system (AS) number. The AS number does not have to beregistered as is the case when routing on the Internet with the Border Gateway Protocol (BGP)routing protocol. However, all routers within an AS must use the same AS number to exchangerouting information with each other.

The networkcommand defines a major network number to which the router is directly connected.The EIGRP routing process looks for interfaces that have an IP address that belongs to thenetworks that are specified with the networkcommand and begins the EIGRP process on theseinterfaces.


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EIGRP Command Example

Command Description

router eigrp 100 Enables the EIGRP routing process for AS 100

network 172.16.0.0 Associates network 172.16.0.0 with the EIGRP routing process

network 10.0.0.0 Associates network 10.0.0.0 with the EIGRP routing process

EIGRP sends updates out of the interfaces in networks 10.0.0.0 and 172.16.0.0. The updatesinclude information about networks 10.0.0.0 and 172.16.0.0 and any other networks that EIGRPlearns.

EIGRP automatically summarizes routes at the classful boundary. In some cases, you might notwant automatic summarization to occur. For example, if you have discontiguous networks, you needto disable automatic summarization to minimize router confusion.

To disable automatic summarization, use the no auto-summary command in the EIGRP routerconfiguration mode.

The show ip protocolscommand displays the parameters and current state of the active routingprotocol process. This command shows the EIGRP AS number. It also displays filtering andredistribution numbers and neighbor and distance information. This also shows the networks thatare currently being advertised on the router by the protocol.

Use the show ip eigrp interfaces [type number] [as-number] command to determine on whichinterfaces EIGRP is active, and to learn information about EIGRP that relates to those interfaces. Ifyou specify an interface by using the type numberoption, only that interface is displayed. Otherwise,all interfaces on which EIGRP is running are displayed. If you specify an AS using the as-numberoption, only the routing process for the specified AS is displayed. Otherwise, all EIGRP processesare displayed. Exam shows the output of the show ip eigrp interfacescommand.

EIGRP Summary

The characteristics of EIGRP follow:

Hybrid routing protocol (distance vector that has link-state protocol characteristics). Uses IP protocol 88. Classless protocol (supports VLSMs). Default composite metric uses bandwidth and delay. You can factor load and reliability into the metric. Sends partial route updates only when there are changes. Support for authentication.

Uses DUAL for loop prevention. By default, equal-cost load balancing. Unequal-cost load balancing with the variancecommand. Administrative distance is 90 for EIGRP internal routes, 170 for EIGRP external routes, and 5 for

EIGRP summary routes. Potential routing protocol for the core of a network; used in large networks.


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EIGRP Configuration

Load IP Routing Initials Prior to Starting

Task 1Configure EIGRP AS 100 on R1 advertise its all networks into EIGRP

Solution:

On R1 :

R1#



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R1(config)#router eigrp 100




R1(config)#exit

R1#

Verification:

On R1:

R1#


Routing Protocol is "eigrp 100"



Default networks flagged in outgoing updates

Default networks accepted from incoming updates

Redistributing: eigrp 100

EIGRP-IPv4 Protocol for AS(100)

Metric weight K1=1, K2=0, K3=1, K4=0, K5=0

NSF-aware route hold timer is 240

Router-ID: 12.0.0.1

Topology : 0 (base)

Active Timer: 3 min

Distance: internal 90 external 170

Maximum path: 4

Maximum hopcount 100

Maximum metric variance 1

Automatic Summarization: enabled

Maximum path: 4


10.0.0.0

12.0.0.0


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R1#

Task 2 From above output we can see that R1 is doing auto-summarization so disable auto-summarization on R1

Solution:

On R1:

R1#





R1(config)#exit

R1#

Verification:

R1#












Router-ID: 12.0.0.1

Topology : 0 (base)


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Active Timer: 3 min


Maximum path: 4



Automatic Summarization: disabled

Maximum path: 4


10.0.0.0

12.0.0.0




R1#

Task 4 configure EIGRP AS 100 on R2 and R3 advertise all the networks and disable auto-

summarization.

Solution:

On R2:

R2#

R2#config terminal







R2(config)#exit

R2#

On R3:

R3#



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R3(config)#exit

R3#

Task 5Verify Routing tables of all 3 routers and test end-to-end connectivity.

Verification:

On R1:

R1#show ip route












D 10.0.0.0/24 is directly connected, Ethernet0/0






D 20.0.0.0 [120/1] via 12.0.0.2, 00:00:24, Serial1/0


D 23.0.0.0 [120/1] via 12.0.0.2, 00:00:24, Serial1/0


D 30.0.0.0 [120/2] via 12.0.0.2, 00:00:24, Serial1/0

R1#


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R1#

R1#ping 23.0.0.2



!!!!!


R1#ping 20.0.0.2



!!!!!


R1#ping 30.0.0.3



!!!!!


R1#

On R2:

R2#

R2#show ip route













D 10.0.0.0 [120/1] via 12.0.0.1, 00:00:14, Serial1/0


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D 30.0.0.0 [120/1] via 23.0.0.3, 00:00:27, Serial1/1

R2#

R2#

R2#ping 10.0.0.1



!!!!!


R2#ping 30.0.0.3



!!!!!


R2#

On R3:

R3#

R3#show ip route











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D 10.0.0.0 [120/2] via 23.0.0.2, 00:00:06, Serial1/0


D 12.0.0.0 [120/1] via 23.0.0.2, 00:00:06, Serial1/0


D 20.0.0.0 [120/1] via 23.0.0.2, 00:00:06, Serial1/0







R3#

R3#

R3#ping 12.0.0.1



!!!!!


R3#ping 20.0.0.2



!!!!!


R3#ping 10.0.0.1

Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 10.0.0.1, timeout is 2 seconds:

!!!!!


R3#

Task 5 Configure all three routers in such manner that they send updates through only

required interfaces

Solution:

On R1


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R1#config terminal




R1(config)#exit

R1#

On R2:

R2#config terminal




R2(config)#exit

R2#

On R3:

R3#config terminal




R3(config)#exit

R3#

Verification:

On R1:

R1#





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Router-ID: 12.0.0.1

Topology : 0 (base)

Active Timer: 3 min


Maximum path: 4



Automatic Summarization: disabled

Maximum path: 4


10.0.0.0

12.0.0.0


Ethernet0/0




R1#

OSPF

Background Information

OSPF protocol was developed due to a need in the internet community to introduce a highfunctionality non-proprietary Internal Gateway Protocol (IGP) for the TCP/IP protocol family. Thediscussion of the creation of a common interoperable IGP for the Internet started in 1988 and did

not get formalized until 1991. At that time the OSPF Working Group requested that OSPF beconsidered for advancement to Draft Internet Standard.

The OSPF protocol is based on link-state technology, which is a departure from the Bellman-Fordvector based algorithms used in traditional Internet routing protocols such as RIP. OSPF has


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introduced new concepts such as authentication of routing updates, Variable Length Subnet Masks(VLSM), route summarization, and so forth.

These chapters discuss the OSPF terminology, algorithm and the pros and cons of the protocol indesigning the large and complicated networks of today.

OSPF versus RIP

The rapid growth and expansion of today's networks has pushed RIP to its limits. RIP has certainlimitations that can cause problems in large networks:

RIP has a limit of 15 hops. A RIP network that spans more than 15 hops (15 routers) is consideredunreachable.

RIP cannot handle Variable Length Subnet Masks (VLSM). Given the shortage of IP addresses andthe flexibility VLSM gives in the efficient assignment of IP addresses, this is considered a majorflaw.

Periodic broadcasts of the full routing table consume a large amount of bandwidth. This is a majorproblem with large networks especially on slow links and WAN clouds.

RIP converges slower than OSPF. In large networks convergence gets to be in the order of minutes.RIP routers go through a period of a hold-down and garbage collection and slowly time-outinformation that has not been received recently. This is inappropriate in large environments andcould cause routing inconsistencies.

RIP has no concept of network delays and link costs. Routing decisions are based on hop counts.The path with the lowest hop count to the destination is always preferred even if the longer path hasa better aggregate link bandwidth and less delays.

RIP networks are flat networks. There is no concept of areas or boundaries. With the introduction ofclassless routing and the intelligent use of aggregation and summarization, RIP networks seem tohave fallen behind.

Some enhancements were introduced in a new version of RIP called RIP2. RIP2 addresses theissues of VLSM, authentication, and multicast routing updates. RIP2 is not a big improvement over

RIP (now called RIP 1) because it still has the limitations of hop counts and slow convergence whichare essential in todayslarge networks.

OSPF, on the other hand, addresses most of the issues previously presented:

With OSPF, there is no limitation on the hop count. The intelligent use of VLSM is very useful in IP address allocation. OSPF uses IP multicast to send link-state updates. This ensures less processing on routers that are

not listening to OSPF packets. Also, updates are only sent in case routing changes occur instead ofperiodically. This ensures a better use of bandwidth.

OSPF has better convergence than RIP. This is because routing changes are propagatedinstantaneously and not periodically.

OSPF allows for better load balancing. OSPF allows for a logical definition of networks where routers can be divided into areas. This limits

the explosion of link state updates over the whole network. This also provides a mechanism foraggregating routes and cutting down on the unnecessary propagation of subnet information.

OSPF allows for routing authentication by using different methods of password authentication. OSPF allows for the transfer and tagging of external routes injected into an Autonomous System.

This keeps track of external routes injected by exterior protocols such as BGP.

This of course leads to more complexity in the configuration and troubleshooting of OSPF networks.Administrators that are used to the simplicity of RIP are challenged with the amount of newinformation they have to learn in order to keep up with OSPF networks. Also, this introduces more

overhead in memory allocation and CPU utilization. Some of the routers running RIP might have tobe upgraded in order to handle the overhead caused by OSPF.


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What Do We Mean by Link-States?

OSPF is a link-state protocol. We could think of a link as being an interface on the router. The stateof the link is a description of that interface and of its relationship to its neighboring routers. Adescription of the interface would include, for example, the IP address of the interface, the mask, thetype of network it is connected to, the routers connected to that network and so on. The collection ofall these link-states would form a link-state database.

Shortest Path First Algorithm

OSPF uses a shorted path first algorithm in order to build and calculate the shortest path to allknown destinations. The shortest path is calculated with the use of the Dijkstra algorithm. Thealgorithm by itself is quite complicated. This is a very high level, simplified way of looking at thevarious steps of the algorithm:

1. Upon initialization or due to any change in routing information, a router generates a link-stateadvertisement. This advertisement represents the collection of all link-states on that router.

2. All routers exchange link-states by means of flooding. Each router that receives a link-state updateshould store a copy in its link-state database and then propagate the update to other routers.

3. After the database of each router is completed, the router calculates a Shortest Path Tree to alldestinations. The router uses the Dijkstra algorithm in order to calculate the shortest path tree. Thedestinations, the associated cost and the next hop to reach those destinations form the IP routingtable.

4. In case no changes in the OSPF network occur, such as cost of a link or a network being added ordeleted, OSPF should be very quiet. Any changes that occur are communicated through link-statepackets, and the Dijkstra algorithm is recalculated in order to find the shortest path.

The algorithm places each router at the root of a tree and calculates the shortest path to eachdestination based on the cumulative cost required to reach that destination. Each router will have itsown view of the topology even though all the routers will build a shortest path tree using the samelink-state database. The following sections indicate what is involved in building a shortest path tree.

OSPF Cost

The cost (also called metric) of an interface in OSPF is an indication of the overhead required tosend packets across a certain interface. The cost of an interface is inversely proportional to thebandwidth of that interface. A higher bandwidth indicates a lower cost. There is more overhead(higher cost) and time delays involved in crossing a 56k serial line than crossing a 10M Ethernet

line. The formula used to calculate the cost is:

Cost = 100/Bandwidth in Mbps


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OSPF Configuration

Load IP Routing Intials Prior to Starting

Task 1Configure OSPF area 0 on R1 advertise its all networks into OSPF use process id 100

Solution:

On R1:


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R1#


R1(config)#router ospf 100

R1(config-router)#network 10.0.0.0 0.0.0.255 area 0



R1(config)#exit

R1#

Verification:

On R1:

R1#



Routing Protocol is "ospf 100"



Router ID 12.0.0.1

Number of areas in this router is 1. 1 normal 0 stub 0 nssa

Maximum path: 4


10.0.0.0 0.0.0.255 area 0

12.0.0.0 0.0.0.255 area 0




R1#

Task 2 configure OSPF area 0 on R2 and R3 advertise all the networks use process id 100

Solution:


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On R2:

R2#

R2#config terminal






R2(config)#exit

R2#

On R3:

R3#






R3(config)#exit

R3#

Task 3Verify Routing tables of all 3 routers and test end-to-end connectivity.

Verification:

R1#show ip route











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O 10.0.0.0/24 is directly connected, Ethernet0/0






O 20.0.0.0 [120/1] via 12.0.0.2, 00:00:24, Serial1/0


O 23.0.0.0 [120/1] via 12.0.0.2, 00:00:24, Serial1/0


O 30.0.0.0 [120/2] via 12.0.0.2, 00:00:24, Serial1/0

R1#

R1#

R1#ping 23.0.0.2



!!!!!


R1#ping 20.0.0.2



!!!!!


R1#ping 30.0.0.3



!!!!!


R1#

On R2:

R2#

R2#show ip route


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O 10.0.0.0 [120/1] via 12.0.0.1, 00:00:14, Serial1/0











O 30.0.0.0 [120/1] via 23.0.0.3, 00:00:27, Serial1/1

R2#

R2#

R2#ping 10.0.0.1



!!!!!


R2#ping 30.0.0.3



!!!!!


R2#


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On R3:

R3#R3#show ip route











O 10.0.0.0 [120/2] via 23.0.0.2, 00:00:06, Serial1/0


O 12.0.0.0 [120/1] via 23.0.0.2, 00:00:06, Serial1/0


O 20.0.0.0 [120/1] via 23.0.0.2, 00:00:06, Serial1/0







R3#

R3#

R3#ping 12.0.0.1



!!!!!


R3#ping 20.0.0.2


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!!!!!


R3#ping 10.0.0.1



!!!!!


R3#

Task 4 Configure all three routers in such manner that they send updates through only required

interfaces

On R1

R1#config terminal




R1(config)#exit

R1#

On R2:

R2#config terminal




R2(config)#exit

R2#

On R3:

R3#config terminal




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R3(config)#exit

R3#

Verification:

On R1:

R1#



Routing Protocol is "ospf 100"



Router ID 12.0.0.1

Number of areas in this router is 1. 1 normal 0 stub 0 nssa

Maximum path: 4


10.0.0.0 0.0.0.255 area 0

12.0.0.0 0.0.0.255 area 0


Ethernet0/0




R1#

Task 5 check ospf neighbors on all the router with show ip ospf neighbor.

Verification:

On R1:

R1#

R1#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface

23.0.0.2 0 FULL/- 00:00:36 12.0.0.2 Serial1/0

R1#

On R2:


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R2#



30.0.0.3 0 FULL/- 00:00:38 23.0.0.3 Serial1/1

12.0.0.1 0 FULL/- 00:00:38 12.0.0.1 Serial1/0

R2#

On R3:



23.0.0.2 0 FULL/- 00:00:34 23.0.0.2 Serial1/0

R3#

Explanation:

In task 1 we have been asked to advertise network in OSPF un likely in EIGRP we give router eigrp

and AS number in EIGRP configuration. But in ospf we have to give process id. When we have to

advertise networks in ospf we have to use wild-card bits.

The best way to calculate wild-card bits for any network is to subtract subnet-mask from broadcast

address.

For e.g.

Wildcard bit for 150.1.1.0/24 will be

255.255.255.255

- 255.255.255.0

= 0.0.0.255

So if you want to advertise network 150.1.1.0/24 in ospf u can advertise with network 1501.1.0 0.0.0.255

area 0

Switch Introduction


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Hubs vs. Switches

Prior to switches, Hubs were the standard for connecting devices on a local area network (LAN).The problem with hubs was that everything that went through them had to share the bandwidth ofthe link. Bandwidth was wasted because all traffic was sent to all devices, and there were a lot ofcollisions because the hub didnt do anything to prevent them. A switch fixes these problems.

What do switches do?

Here are some facts about switches that you should know:

Switches work at Layer 2 of the OSI model, not Layer 1 like a hub Switches switch Ethernet frames Switches dont look at IP address information, only Ethernet MAC addresses Switches keeps a table of all MAC addresses traversing the switch and what port they are on (this

table is called the bridge forwarding table or CAM table) Switches only sends traffic to the devices that are the destination for that traffic, saving bandwidth Each device connected to the switch gets the full bandwidth of the switch port because the switch

prevents collisions

Flooding

Now that you know that the switch has the bridge forwarding table and uses that to intelligently sendtraffic, a common question is, what if the destination MAC address for the traffic that the switchreceives is not in the bridge forwarding table? What does the switch do with that Ethernet frame?The answer is that the switch will flood that frame out all ports on the switch. The switch will thenmonitor the traffic for the response from that frame and see what device, on what port, responded tothat flooded frame. That information will be put in the bridge forwarding table so that, next time, theswitch wont have to flood that traffic

Port speed & Duplex

Of particular importance when it comes to switches are port speed and duplex. The speed of a portcan be set to 10Mb, 100Mb, or 1000Mb (1GB), or Auto negotiate, depending on what the sw

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