Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CCIE Lab > CCIE LAB 06 OSPF > Flashcards

CCIE LAB 06 OSPF Flashcards

Master the OSPF Lab scenarios

1
Q

6.3 OSPF DR/BDR Election Manipulation
• Configure R6 to be elected the OSPF Designated Router for VLANs 67 and 146.
• If R6 goes down R1 should take over the DR status for VLAN 146.
• When R6 comes back up it should become the BDR.
• Modify the DR/BDR election on the Frame Relay network to ensure that if
R5’s connection to the Frame Relay network goes down and comes back
up, full reachability is still maintained.

A 
R6:
interface FastEthernet0/0.67
ip ospf priority 255
!
interface FastEthernet0/0.146
ip ospf priority 255

All other devices:
interface Serial0/0
ip ospf priority 0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

6.7 OSPF Network Loopback

• Modify the network type of a loopback interface so that the links are not advertised as host routes.

A

interface Loopback0

ip ospf network point-to-point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

6.8 OSPF Path Selection with Auto-Cost
• Modify the global OSPF cost calculation of all devices so that a Ten Gigabit Ethernet interface has a cost of 3, and an OC-3 link has a cost of 193.

A

router ospf 1

auto-cost reference-bandwidth 30000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

6.9 OSPF Path Selection with Cost
• Using the interface level ip ospf cost command modify the OSPF domain so that traffic from SW4 going to the Loopback 0 network of R6 uses the point-to-point Serial link between R4 and R5.

A

R5:
interface Serial0/1/0
ip ospf cost 10000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

6.10 OSPF Path Selection with Bandwidth
• Using the interface level bandwidth keyword modify the OSPF domain so that traffic from R6 to the Loopback 0 network of SW2 is first sent to R1.

A

R1:
interface Serial0/0
bandwidth 10000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

6.11 OSPF Path Selection with Per-Neighbor Cost
• The Frame Relay PVC between R1 & R5 has been provisioned with 512Kbps of bandwidth by the service provider, while the PVC between R4 & R5 has been provisioned at 768Kbps. Configure per-neighbor cost values on R5 to reflect the underlying bandwidth of the Frame Relay circuits connecting it to R1 and R4.

A

R5:
router ospf 1
neighbor 155.1.0.1 cost 58593
neighbor 155.1.0.4 cost 39062

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

6.12 Repairing Discontiguous OSPF Areas with Virtual-Links
• Configure the network so that full reachability is maintained if R3’s connection to SW1 goes down.
• Do not apply any configuration onto R4 to solve this task.

A

R1:
router ospf 1
area 1 virtual-link 150.1.6.6

R6:
router ospf 1
area 1 virtual-link 150.1.1.1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

6.13 OSPF Path Selection with Non-Backbone Transit Areas
• Configure R4’s Frame Relay and point-to-point Serial links connecting to R5 to have an OSPF cost of 1.
• Modify the SPF calculation in the OSPF domain so that R6 cannot use R4 to reach area 0 by transiting area 1.

A

R1:
router ospf 1
no capability transit

R4:
interface Serial0/0/0
ip ospf cost 1
!
interface Serial0/1/0
ip ospf cost 1

R6:
router ospf 1
no capability transit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

6.14 OSPF Path Selection with Virtual-Links
• Configure the OSPF domain so that traffic from SW3 going to OSPF area 51 transits the point-to-point Serial link between R3 and R2.

A

R2:
router ospf 1
area 5 virtual-link 150.1.3.3

R3:
interface Serial1/3
ip ospf cost 1
!
router ospf 1
area 5 virtual-link 150.1.2.2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

6.15 OSPF Demand Circuit
• The point-to-point connection between R4 and R5 is a low-speed Serial link. Configure the OSPF demand circuit feature on this link to reduce periodic OSPF hello transmission and paranoid update flooding.

A

R4:
interface Serial0/1/0
ip ospf demand-circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

6.16 OSPF Flooding Reduction

• Configure interfaces so that links in OSPF area 3 do not participate in periodic paranoid update LSA flooding.

A

interface Vlan8

ip ospf flood-reduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

6.17 OSPF Clear Text Authentication
• Configure clear-text OSPF authentication for all adjacencies in area 2 using the password CLEARKEY. Enable authentication on all interfaces in area 2 with one single command.

A 
interface _
ip ospf authentication-key CLEARKEY
!
router ospf 1
area 2 authentication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

6.17 OSPF Clear Text Authentication

• R3, R6, and SW3 should only enable authentication on their links connecting to SW1.

A

interface FastEthernet0/0 (Vlan79)
ip ospf authentication
ip ospf authentication-key CLEARKEY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

6.18 OSPF MD5 Authentication
• Configure MD5 based OSPF authentication for all adjacencies in area 0, including the Virtual-Links, using the password MD5KEY with a single command.

A 
interface Serial0/0
ip ospf message-digest-key 1 md5 MD5KEY
!
router ospf 1
area 0 authentication message-digest
area 1 virtual-link 150.1.6.6 message-digest-key 1 md5 MD5KEY
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

6.18 OSPF MD5 Authentication

Configure MD5 based OSPF authentication and enable MD5 authentication on a per interface basis.

A

interface Serial0/0
ip ospf authentication message-digest
ip ospf message-digest-key 1 md5 MD5KEY
!
router ospf 1
area 5 virtual-link 150.1.3.3 authentication message-digest
area 5 virtual-link 150.1.3.3 message-digest-key 1 md5 MD5KEY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

6.19 OSPF Null Authentication

• Modify SW1 so that if a new router is added to area 2 on VLAN 7 it does not require authentication.

A

interface Vlan7

ip ospf authentication null

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

6.20 OSPF MD5 Authentication with Multiple Keys
• Enable MD5 authentication in OSPF area 1.
• R1 should authenticate R6 using the password R1R6KEY.
• R4 should authenticate R6 using the password R4R6KEY.

A

R1:
interface FastEthernet0/0
ip ospf authentication message-digest
ip ospf message-digest-key 16 md5 R1R6KEY

R4:
interface FastEthernet0/1
ip ospf authentication message-digest
ip ospf message-digest-key 46 md5 R4R6KEY

R6:
interface FastEthernet0/0.146
ip ospf authentication message-digest
ip ospf message-digest-key 16 md5 R1R6KEY
ip ospf message-digest-key 46 md5 R4R6KEY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

6.21 OSPF Internal Summarization
• Configure R5 to advertise a summary route for the VLAN 8 and 10 prefixes as they are sent into area 0.
• This summary should be as specific as possible while still encompassing all addresses in both subnets.

A

router ospf 1

area 3 range 155.1.8.0 255.255.252.0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

6.22 OSPF Path Selection with Summarization
• Configure R3 to originate the summary route 155.1.6.0/23 in order to force traffic destined to VLAN 7 to transit R6.
• If R6’s connection to VLAN 146 is down, traffic for VLAN 7 should transit R3.

A

R3:
router ospf 1
area 2 range 155.1.6.0 255.255.254.0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

6.23 OSPF External Summarization
• Redistribute between RIPv2 and OSPF on R4.
• R4 should advertise two summary routes that have a cost of 50 into OSPF for the prefixes learned from BB3.

A 
router ospf 1
summary-address 30.0.0.0 255.252.0.0
summary-address 31.0.0.0 255.252.0.0
redistribute rip metric 50 subnets
!
router rip
redistribute ospf 1 metric 1
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

6.23 OSPF External Summarization
• Redistribute between EIGRP and OSPF on R6.
• R6 should advertise a single summary route into OSPF for the prefixes learned from BB1 that has a cost of 100, and includes the cost needed to reach R6.

A

router eigrp 10
redistribute ospf 1 metric 10000 1000 255 1 1500
!
router ospf 1
summary-address 200.0.0.0 255.255.252.0
redistribute eigrp 10 metric 100 metric-type 1 subnets

22
Q

6.24 OSPF Stub Areas
• Configure OSPF area 3 so that R5 filters External routes out as they are
sent from area 0 to area 3.
• Devices in area 3 should still have reachability to routes external to the
OSPF domain.

A

All devices in Area 3:

router ospf 1
area 3 stub

23
Q

6.25 OSPF Totally Stubby Areas
• Configure OSPF area 3 so that R5 filters Inter-Area and External routes as
they are sent from area 0 to area 3.
• Devices in area 3 should still have reachability to routes external to the
OSPF domain.

A

Only on R5:

router ospf 1
area 3 stub no-summary

24
Q

6.26 OSPF Not-So-Stubby Areas
• Configure OSPF area 2 so that R3 filters External routes out as they are
sent from area 0 to area 2.
• R6 should still be allowed to redistribute EIGRP into OSPF.

A

All devices in Area 2:

router ospf 1
area 2 nssa

25
Q

6.27 OSPF Not-So-Stubby Areas and Default Routing
• Configure R3 to advertise a default route into area 2.
• This default route should have a cost of 500.

A

router ospf 1
area 2 nssa default-information-originate
area 2 default-cost 500

26
Q

6.28 OSPF Not-So-Totally-Stubby Areas
• Modify the area 2 configuration so that R3 filters Inter-Area and External routes as they are sent from area 0 to area 2.
• R6 should still be allowed to redistribute EIGRP into OSPF.

A

R3:
router ospf 1
no area 2 nssa
area 2 nssa no-summary

27
Q

6.29 OSPF Stub Areas with Multiple Exit Points
• Modify area 2 in such a way that traffic from devices in area 2 going to area 3 uses R6 as the exit point, while traffic from area 2 going to the RIP
routes learned from BB3 uses R3.
• If R3 loses its connection to area 2, traffic for External destinations should be rerouted to R6.
• If R6 loses its connection to area 2, traffic for Inter-Area destinations should be rerouted to R3.
• Do not modify the cost of any links in area 2 to accomplish this.

A

R3:
router ospf 1
area 2 nssa no-summary

R6:
router ospf 1
area 2 nssa default-information-originate

28
Q

6.30 OSPF NSSA Type-7 to Type-5 Translator Election
• Create a new Loopback 9 interface on SW3 with the IP address
9.9.9.9/32, and redistribute it into OSPF.
• Modify the OSPF domain so that only R3 advertises this route into area 0,
but traffic from R5 going to this destination transits R6.
• If R6 is down this traffic should be rerouted to R3.

A 
R3:
interface FastEthernet0/0
ip ospf cost 1000
!
router ospf 1
router-id 150.1.30.30
SW3:
interface Loopback9
ip address 9.9.9.9 255.255.255.255
!
router ospf 1
redistribute connected subnets
29
Q

6.31 OSPF NSSA Redistribution Filtering
• Configure area 3 as an NSSA so R5 blocks all LSA types 3, 4, and 5 and replaces them with a default route.
• Modify area 3 so that R5’s redistributed Loopback is injected into area 0 as LSA Type-5, but is not injected into area 3 as LSA Type-7.

A

R5:
router ospf 1
redistribute connected subnets
area 3 nssa no-redistribution no-summary

30
Q

6.32 OSPF LSA Type-3 Filtering
• Configure LSA Type-3 Filtering on R5 so that devices in area 0 do not have reachability information about the layer 3 EtherChannel link between SW2 and SW4 or SW4’s Loopback 0 interface.
• Configure LSA Type-3 Filtering on R2 so that devices in area 51 do not have reachability information about the Loopback 0 interface of R5; this should not affect devices in area 5.

A

R2:
ip prefix-list R5_LOOPBACK deny 150.1.5.5/32
ip prefix-list R5_LOOPBACK permit 0.0.0.0/0 le 32
!
router ospf 1
area 51 filter-list prefix R5_LOOPBACK in

R5:
ip prefix-list AREA_3_ROUTES deny 150.1.10.10/32
ip prefix-list AREA_3_ROUTES deny 155.1.108.0/24
ip prefix-list AREA_3_ROUTES permit 0.0.0.0/0 le 32
!
router ospf 1
area 3 filter-list prefix AREA_3_ROUTES out

31
Q

6.33 OSPF Forwarding Address Suppression
• Modify R5’s NSSA configuration so that devices outside of area 3 maintain connectivity to SW4’s redistributed Loopback 10.10.10.10/32.

A

R5:
router ospf 1
area 3 nssa no-redistribution no-summary translate type7 suppress-fa

32
Q

6.34 OSPF Default Routing
• Configure R6 with a static default route pointing to BB1.
• Configure R6 to originate an external type-2 default route with a metric of 60 into OSPF as long as the static default route is installed in the routing table.
• Do not use a route-map to accomplish this.
• Configure R4 to originate an external type-1 default route with a metric of 40 regardless of whether it has a default route already installed in the routing table.

A

R4:
router ospf 1
default-information originate always metric 40 metric-type 1

R6:
ip route 0.0.0.0 0.0.0.0 54.1.1.254
!
router ospf 1
default-information originate metric 60
33
Q

6.35 OSPF Conditional Default Routing

• Configure R6 to originate a default route into OSPF, but only if the local Serial interface connecting to BB1 is up.

A 
R6:
router ospf 1
default-information originate always route-map TRACK_LINK_TO_BB1
!
ip prefix-list LINK_TO_BB1 seq 5 permit 54.1.1.0/24
!
route-map TRACK_LINK_TO_BB1 permit 10
match ip address prefix-list LINK_TO_BB1
34
Q

6.36 OSPF Reliable Conditional Default Routing
• Remove the previous default route advertisement on R4.
• Configure an IP SLA instance on R4 to check ICMP reachability to BB3 every five seconds.
• R4 should advertise a default route into OSPF, but only if the SLA monitoring reports its status as OK.

A 
R4:
ip sla 1
icmp-echo 204.12.30.254
timeout 2000
frequency 5
ip sla schedule 1 life forever start-time now
!
track 1 rtr 1
!
ip route 169.254.0.1 255.255.255.255 Null0 track 1
!
ip prefix-list PLACEHOLDER seq 5 permit 169.254.0.1/32
!
route-map TRACK_PLACEHOLDER permit 10
match ip address prefix-list PLACEHOLDER
!
router ospf 1
default-information originate always route-map TRACK_PLACEHOLDER
35
Q

6.37 OSPF Filtering with Distribute-Lists

• Configure distribute-list filtering on R5 that it does not install routes to the Loopback 0 networks of R1 and R2.

A 
R5:
router ospf 1
distribute-list 1 in
!
access-list 1 deny 150.1.1.1
access-list 1 deny 150.1.2.2
access-list 1 permit any
36
Q

6.38 OSPF Summarization and Discard Routes
• Configure R5 to advertise the summary 150.1.0.0/22 into area 3.
• Ensure that R5, SW2, and SW4 can still reach the Loopback 0 networks of R1 and R2, even with the previously configured distribute-list filter applied.

A

R5:
router ospf 1
no discard-route internal
area 0 range 150.1.0.0 255.255.252.0

37
Q

6.39 OSPF Filtering with Administrative Distance
• Configure administrative distance filtering on R5 so that traffic going towards the VLAN 67 network is sent towards R3.

A 
R5:
router ospf 1
distance 255 150.1.6.6 0.0.0.0 67
!
access-list 67 permit 155.1.67.0
38
Q

6.40 OSPF Filtering with Route-Maps

• Configure route-map filtering on R6 so that traffic going towards the Loopback 0 network of R3 is sent towards R1.

A 
R6:
router ospf 1
distribute-list route-map DENY_R3_LOOPBACK_FROM_R4 in
!
access-list 3 permit 150.1.3.3
access-list 4 permit 155.1.146.4
!
route-map DENY_R3_LOOPBACK_FROM_R4 deny 10
match ip address 3
match ip next-hop 4
!
route-map DENY_R3_LOOPBACK_FROM_R4 permit 20
39
Q

6.41 OSPF NSSA ABR External Prefix Filtering
• Configure area 2 as an NSSA.
• Configure summarization on R3 so that devices outside of area 2 do not have a route to the network 200.0.0.0/24.
• This filter should not affect any other prefixes.

A

R3:
router ospf 1
area 2 nssa
summary-address 200.0.0.0 255.255.255.0 not-advertise

40
Q

6.42 OSPF Database Filtering
• Configure SW1 so that SW3 cannot learn any OSPF routes from SW1, but SW1 can still learn OSPF routes from SW3.
• Use an interface level command to accomplish this.

A

SW1:
interface Vlan79
ip ospf database-filter all out

41
Q
  • Configure R5 so that R2 cannot learn from R5, but R5 can still learn OSPF routes from R2.
  • Do not use an interface level command to accomplish this
A

R5:
router ospf 1
neighbor 155.1.0.2 database-filter all out

42
Q

6.43 OSPF Stub Router Advertisement

• Configure R4 to advertise the maximum metric value to all neighbors inside its Type-1 Router LSA.

A

R4:
router ospf 1
max-metric router-lsa

43
Q

6.44 OSPF Interface Timers
• Configure R5 to send OSPF hello packets out its link to the Frame Relay
network every five seconds, and wait for seven seconds before declaring a neighbor down.

A

R5:
interface Serial0/0/0
ip ospf hello-interval 5
ip ospf dead-interval 7

44
Q

6.44 OSPF Interface Timers

• Configure R4 to send OSPF hello packets every 250ms on the point-to-point link to R5.

A

interface Serial0/1/0

ip ospf dead-interval minimal hello-multiplier 4

45
Q

6.45 OSPF Global Timers
• Configure SPF throttling to start new re-calculation at least 100ms after a new LSA arrives. The second SPF calculation should occur in no less than 1s after the first one, and the maximum wait time should be no more than 10 seconds.

A

router ospf 1

timers throttle spf 100 1000 10000

46
Q

6.45 OSPF Global Timers
o Configure LSA pacing to wait at least 50ms between consecutive link-state updates. LSA retransmissions should be paced at least 75ms apart.

A

router ospf 1
timers pacing flood 50
timers pacing retransmission 75

47
Q

6.45 OSPF Global Timers
o Configure LSA throttling to generate subsequent LSAs after 10ms, to wait at least 4 seconds to generate the next LSA, and no more than 6 seconds between generation of the same LSA.

A

router ospf 1

timers throttle lsa all 10 4000 6000

48
Q

6.45 OSPF Global Timers

o Configure LSA arrival throttling to wait 2 seconds between reception of the same LSA from a neighbor.

A

router ospf 1

timers lsa arrival 2000

49
Q

6.46 OSPF Resource Limiting
• Configure R4 so that no more than 5000 LSAs can exist in the database.
• No more than 500 of these routes should be originated through redistribution.
• R4’s OSPF process should be allowed to use up to 20% CPU utilization before allowing interrupts from higher priority processes.

A 
R4:
router ospf 1
max-lsa 5000
redistribute maximum-prefix 500
process-min-time percent 20
50
Q

6.47 Miscellaneous OSPF Features

• Configure SW4 so that it goes not generate a log message upon receipt of a Type-6 LSA advertisement.

A

router ospf 1

ignore lsa mospf

51
Q

6.47 Miscellaneous OSPF Features
• Configure SW4 so that it does not take the MTU value into account when establishing adjacencies on its Port-Channel1 interface.

A

interface Port-channel1

ip ospf mtu-ignore

52
Q

6.47 Miscellaneous OSPF Features
• Configure SW4 to reflect the following output:

Rack1SW4#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
Rack1SW2 1 FULL/BDR 00:00:38 155.1.108.8 Portchannel1

A

SW4:
ip host Rack1SW2 150.1.8.8
!
ip ospf name-lookup

CCIE Lab (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions