SPRI - OSPF

Question 1

Qual a formula do custo OSPF ?

Answer 1

Reference BW / Link BW

Question 2

O parametro de banda informado no comando auto-cost reference-bandwidth é dado em Mbps

Answer 2

verdadeiro

Question 3

Rotas E2 são melhores que N2

Answer 3

Falso

Question 4

Rotas E2 são melhores que N1

Answer 4

Falso

Question 5

Descreva best path selection do OSPF

Answer 5

Intra area
Interarea
NSSA 1
External 1
NSSA 2
External 2

para rotas de mesmo tipo, menor custo

Question 6

Quais problemas a sumarização OSPF resolve

Answer 6

large routing tables

frequent LSA flooding throughout the AS.

Question 7

At least one subnet must be within the summary address range in order for the ABR to generate the summary type 3 LSA.

Answer 7

true

Question 8

Qual efeito do comando abaixo?

no compatible rfc1583

Answer 8

OSPF usa o custo máximo ao invés do mínimo para gerar a rota sumarizada

Question 9

O tipo de rota externa E2 não incrementa seu custo

Answer 9

falso, E1

Question 10

O comando summary-prefix pode ser usado no IOS para sumarização de rotas no ASBR

Answer 10

Falso, summary-address IOS e summary-prefix no IOS-XR

Question 11

O virtual link pode ser usado como solução para roteamento suboptimo

Answer 11

verdadeiro, em especial quando um

Question 12

About Virtual Links:

They traverse stubby or NSSA areas.

Answer 12

False

Question 13

About Virtual Links:

They also cannot traverse unnumbered links.

Answer 13

True

Question 14

As quickly as possible after an RP failover, the Cisco NSF-capable router sends an OSPF Cisco NSF signal to neighboring Cisco NSF-aware devices. This signal is in the form of a link-local LSA requests that the neighbor relationship with this router should not be reset.

Answer 14

true

Question 15

Cisco supports the BFD synchronous mode

Answer 15

false, asynchronous.

O que significa que somente após troca completa de mensagens a adjacencia será estabelecida ?

Question 16

The BFD protocol has discovery mechanisms to detect neighbors.

Answer 16

False, does not have an discovery mechanism

Question 17

BFD confia em pacotes de controle e echo

Answer 17

verdadeiro

Question 18

No modo echo o Router-A gera um pacote BFD com destino ao seu proprio IP porém com mac de destino do next hop Router-B, o Router-B ao receber faz um L3 lookup e devolve o pacote para o Router-A

Answer 18

Verdadeiro

Question 19

Link LSAs (type 8): Have local-link flooding scope.

inform other routers attached to the link of a list of prefixes to associate with the link, and allow the router to assert a collection of option bits to associate with the network LSA that will be originated for the link.

Answer 19

true

Question 20

In OSPFv3, a routing process is required to be explicitly created. Enabling OSPFv3 on an interface will cause a routing process, and its associated configuration, to be created

Answer 20

False, a process does not need to be explicitly created.

Question 21

Prefix Suppression
The easiest way to reduce the size of the LSDB is to exclude all transport links from IS-IS. If all loopback and edge interfaces are marked as passive, then only passive interfaces can be propagated via IS-IS.

Answer 21

Verdadeiro

Question 22

No OSPF o prefix-suppression que apenas as loopbacks sejam anunciadas e o comando que ativa é o advertise passive-only

Answer 22

Falso, é no ISIS, no OSPF é o prefix-supression em modo global

Question 23

No ospf o comando para controlar o anuncio de prefixos a nível de interface é o :

R23(config-if)#ospf advertise prefix

Answer 23

falso é no isis, o comando no ospf seria:
R23(config-if)#ip ospf prefix-suppression

no isis:
isis advertise prefix

Question 24

Rota E2 é rota externa menos preferida

Answer 24

Verdadeiro

Question 25

Rota N1 é rota externa mais preferida

Answer 25

Verdadeiro