Question 1mediummultiple choice
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A network engineer runs the following command on Router R1:
R1# show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/DROTHER 00:00:35 192.168.12.2 GigabitEthernet0/0 10.1.1.3 1 FULL/DR 00:00:32 192.168.13.3 GigabitEthernet0/1
Based on this output, which statement is correct?
A network engineer runs the following command on Router R1:
R1# show ip ospf database
OSPF Router with ID (10.1.1.1) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
10.1.1.1 10.1.1.1 120 0x80000002 0x00A1B2 3 10.1.1.2 10.1.1.2 200 0x80000001 0x00B2C3 2 10.1.1.3 10.1.1.3 150 0x80000003 0x00C3D4 4
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
192.168.12.2 10.1.1.2 180 0x80000001 0x00D4E5
Based on this output, what can be concluded?
A network engineer runs the following command on Router R1:
R1# show ip ospf interface GigabitEthernet0/0
GigabitEthernet0/0 is up, line protocol is up Internet Address 192.168.12.1/24, Area 0 Process ID 1, Router ID 10.1.1.1, Network Type BROADCAST, Cost: 10 Transmit Delay is 1 sec, State BDR, Priority 1 Designated Router (ID) 10.1.1.2, Interface address 192.168.12.2 Backup Designated router (ID) 10.1.1.1, Interface address 192.168.12.1 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 oob-resync timeout 40 Hello due in 00:00:03
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 10.1.1.2 (Designated Router) Suppress hello for 0 neighbor(s)
Based on this output, which statement is correct?
A network engineer runs the following command on Router R1:
R1# show ip route ospf
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, H - NHRP, l - LISP a - application route + - replicated route, % - next hop override
Gateway of last resort is not set
O 10.2.2.0/24 [110/20] via 192.168.12.2, 00:12:34, GigabitEthernet0/0
O IA 10.3.3.0/24 [110/30] via 192.168.13.3, 00:10:21, GigabitEthernet0/1
Based on this output, what can be determined?
A network engineer runs the following command on Router R1:
R1# show ip ospf neighbor 10.1.1.2 Neighbor 10.1.1.2, interface address 192.168.12.2
In the area 0 via interface GigabitEthernet0/0
Neighbor priority is 1, State is FULL, 6 state changes
DR is 10.1.1.2, BDR is 10.1.1.1 Options is 0x12 (L L S R) Dead timer due in 00:00:36
Neighbor is up for 00:15:42
Index 1/1/1, retransmission queue length 0, number of retransmission 0 First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0) Last retransmission scan length is 0, time is 0 msec Last retransmission scan time is 0 msec
Based on this output, what is the role of Router R1 on this segment?
A network engineer runs the following command on Router R1:
R1# show ip ospf database router 10.1.1.2
OSPF Router with ID (10.1.1.1) (Process ID 1)
Router Link States (Area 0)
LS age: 150 Options: (No TOS-capability, DC) LS Type: Router Links Link State ID: 10.1.1.2 Advertising Router: 10.1.1.2 LS Seq Number: 80000002 Checksum: 0x1234 Length: 48 Number of Links: 2
Link connected to: a Transit Network (Link ID) Designated Router address: 192.168.12.2 (Link Data) Router Interface address: 192.168.12.2 Number of TOS metrics: 0 TOS 0 Metrics: 10
Link connected to: a Stub Network (Link ID) Network/subnet number: 10.2.2.0 (Link Data) Network Mask: 255.255.255.0 Number of TOS metrics: 0 TOS 0 Metrics: 10
Based on this output, which statement is correct?
A network engineer runs the following command on Router R1:
R1# show ip ospf virtual-links
Virtual Link OSPF_VL0 to router 10.1.1.3 is up Run as demand circuit DoNotAge LSA allowed. Transit area 1, via interface GigabitEthernet0/0, Cost of using 10 Transmit Delay is 1 sec, State POINT_TO_POINT, Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 Hello due in 00:00:08 Adjacency State FULL
Based on this output, what can be concluded?
A network engineer runs the following command on Router R1:
R1# show ip ospf neighbor detail Neighbor 10.1.1.4, interface address 192.168.14.4
In the area 0 via interface GigabitEthernet0/2
Neighbor priority is 1, State is 2WAY, 2 state changes
DR is 10.1.1.1, BDR is 10.1.1.4 Options is 0x12 (L L S R) Dead timer due in 00:00:38
Neighbor is up for 00:05:22
Index 1/1/1, retransmission queue length 0, number of retransmission 0 First 0x0(0)/0x0(0) Next 0x0(0)/0x0(0) Last retransmission scan length is 0, time is 0 msec Last retransmission scan time is 0 msec
Based on this output, what is the problem?
A network engineer runs the following command on Router R1:
R1# show ipv6 ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/BDR 00:00:35 FE80::2 GigabitEthernet0/0 10.1.1.3 1 FULL/DR 00:00:32 FE80::3 GigabitEthernet0/1
Based on this output, which statement is correct regarding OSPFv3?
Examine the following OSPF configuration on router R1:
router ospf 1 network 10.0.0.0 0.255.255.255 area 0 network 192.168.1.0 0.0.0.255 area 1
What is the effect of this configuration?
Consider this OSPFv3 configuration on router R2:
ipv6 router ospf 10 router-id 2.2.2.2
area 0 authentication ipsec spi 256 md5 1234567890abcdef1234567890abcdef interface GigabitEthernet0/0
ipv6 address 2001:db8:1::1/64 ipv6 ospf 10 area 0
What is the effect of this configuration?
Examine this OSPF configuration snippet on router R3:
router ospf 1 network 10.1.1.0 0.0.0.255 area 0
default-information originate always
What is the effect of the default-information originate always command?
Consider this OSPF configuration on router R4:
router ospf 1 network 192.168.1.0 0.0.0.255 area 0 neighbor 10.0.0.2
What is the effect of the neighbor statement?
Examine this OSPF configuration on router R5:
router ospf 1 network 10.0.0.0 0.255.255.255 area 0 passive-interface default no passive-interface GigabitEthernet0/0
What is the effect of the passive-interface default command?
Consider this OSPF configuration on router R6:
router ospf 1 network 10.0.0.0 0.255.255.255 area 0 area 0 stub
What is the effect of the area 0 stub command?
A network engineer runs the following command to troubleshoot an OSPF adjacency issue:
R1# debug ip ospf adj *Mar 1 00:12:34.567: OSPF-1 ADJ RtrA: Interface GigabitEthernet0/0 going Up *Mar 1 00:12:34.568: OSPF-1 ADJ RtrA: 2 Way Communication to 10.1.1.2 on GigabitEthernet0/0, state 2WAY *Mar 1 00:12:34.570: OSPF-1 ADJ RtrA: NBR 10.1.1.2: Our router ID 1.1.1.1, his router ID 2.2.2.2 *Mar 1 00:12:34.571: OSPF-1 ADJ RtrA: NBR 10.1.1.2: Neighbor is not DR, state 2WAY *Mar 1 00:12:34.572: OSPF-1 ADJ RtrA: NBR 10.1.1.2: DR is 10.1.1.2, BDR is 10.1.1.1 *Mar 1 00:12:34.573: OSPF-1 ADJ RtrA: NBR 10.1.1.2: Build the Start DBD *Mar 1 00:12:34.574: OSPF-1 ADJ RtrA: NBR 10.1.1.2: Master/Slave negotiation done *Mar 1 00:12:34.576: OSPF-1 ADJ RtrA: NBR 10.1.1.2: Exchange done, loading started *Mar 1 00:12:34.578: OSPF-1 ADJ RtrA: NBR 10.1.1.2: Loading done *Mar 1 00:12:34.580: OSPF-1 ADJ RtrA: NBR 10.1.1.2: Full
What does this output indicate?
A network engineer runs the following command to troubleshoot OSPF route propagation:
R1# show ip ospf database router 2.2.2.2
OSPF Router with ID (1.1.1.1) (Process ID 1)
Router Link States (Area 0)
LS age: 45 Options: (No TOS-capability, DC) LS Type: Router Links Link State ID: 2.2.2.2 Advertising Router: 2.2.2.2 LS Seq Number: 80000005 Checksum: 0x1234 Length: 48 Number of Links: 2
Link connected to: a Transit Network (Link ID) Designated Router address: 10.1.1.2 (Link Data) Router Interface address: 10.1.1.2 Number of TOS metrics: 0 TOS 0 Metrics: 10
Link connected to: a Stub Network (Link ID) Network/subnet number: 192.168.1.0 (Link Data) Network Mask: 255.255.255.0 Number of TOS metrics: 0 TOS 0 Metrics: 10
What does this output indicate?
A network engineer runs the following command to verify OSPF interface details:
R1# show ip ospf interface gigabitethernet0/0 detail
GigabitEthernet0/0 is up, line protocol is up Internet Address 10.1.1.1/24, Area 0 Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 10 Transmit Delay is 1 sec, State BDR, Priority 1 Designated Router (ID) 2.2.2.2, Interface address 10.1.1.2 Backup Designated router (ID) 1.1.1.1, Interface address 10.1.1.1 Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5 oob-resync timeout 40 Hello due in 00:00:03 Supports Link-local Signaling (LLS) Cisco NSF helper support enabled IETF NSF helper support enabled Can be protected by per-prefix Loop-Free Fast Reroute Can be used for per-prefix Loop-Free Fast Reroute repair paths Index 1/1, flood queue length 0 Next 0(0)/0(0) Last flood scan length is 1, maximum is 25 Last flood scan time is 0 msec, maximum is 4 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 2.2.2.2 (Designated Router) Suppress hello for 0 neighbor(s)
What does this output indicate?
A network engineer runs the following command to troubleshoot OSPF route redistribution:
R1# show ip ospf database external 5.5.5.5
OSPF Router with ID (1.1.1.1) (Process ID 1)
Type-5 AS External Link States
LS age: 120 Options: (No TOS-capability, DC, Upward) LS Type: AS External Link Link State ID: 5.5.5.5 (External Network Number) Advertising Router: 3.3.3.3 LS Seq Number: 80000001 Checksum: 0xABCD Length: 36 Network Mask: /32 Metric Type: 2 (Larger than any link state path) TOS: 0 Metric: 20 Forward Address: 0.0.0.0 External Route Tag: 0
What does this output indicate?
A network engineer runs the following command to troubleshoot OSPFv3 adjacency:
R1# debug ipv6 ospf adj *Mar 1 00:15:23.456: OSPFv3-1-IPv6 ADJ Gi0/0: Rcv pkt from 2001:DB8:1::2, src 2001:DB8:1::2, area 0 *Mar 1 00:15:23.457: OSPFv3-1-IPv6 ADJ Gi0/0: Nbr 2.2.2.2: Our address 2001:DB8:1::1, his address 2001:DB8:1::2 *Mar 1 00:15:23.458: OSPFv3-1-IPv6 ADJ Gi0/0: Nbr 2.2.2.2: Neighbor is not DR, state 2WAY *Mar 1 00:15:23.459: OSPFv3-1-IPv6 ADJ Gi0/0: Nbr 2.2.2.2: DR is 2001:DB8:1::2, BDR is 2001:DB8:1::1 *Mar 1 00:15:23.460: OSPFv3-1-IPv6 ADJ Gi0/0: Nbr 2.2.2.2: Build the Start DBD *Mar 1 00:15:23.462: OSPFv3-1-IPv6 ADJ Gi0/0: Nbr 2.2.2.2: Master/Slave negotiation done *Mar 1 00:15:23.464: OSPFv3-1-IPv6 ADJ Gi0/0: Nbr 2.2.2.2: Exchange done, loading started *Mar 1 00:15:23.466: OSPFv3-1-IPv6 ADJ Gi0/0: Nbr 2.2.2.2: Loading done *Mar 1 00:15:23.468: OSPFv3-1-IPv6 ADJ Gi0/0: Nbr 2.2.2.2: Full
What does this output indicate?
A network engineer runs the following command to verify OSPFv3 database:
R1# show ipv6 ospf database router 2.2.2.2
OSPFv3 Router with ID (1.1.1.1) (Process ID 1)
Router Link States (Area 0)
LS age: 60 LS Type: Router Links Link State ID: 0.0.0.0 Advertising Router: 2.2.2.2 LS Seq Number: 80000003 Checksum: 0x5678 Length: 40 Number of Links: 1
Link connected to: a Transit Network (Link ID) Interface ID: 2 (Link Data) Neighbor Interface ID: 1 Number of TOS metrics: 0 TOS 0 Metrics: 10
What does this output indicate?
A network engineer runs the following command to troubleshoot OSPF neighbor states:
R1# show ip ospf neighbor detail Neighbor 2.2.2.2, interface address 10.1.1.2
In the area 0 via interface GigabitEthernet0/0
Neighbor priority is 1, State is FULL, 6 state changes
DR is 10.1.1.2, BDR is 10.1.1.1 Options is 0x42 (LLS, DC) LLS Options is 0x1 (LR) Dead timer due in 00:00:36
Neighbor is up for 00:12:34
Index 1/1/1 Retransmission queue length 0, number of retransmission 1 First 0x0(0)/0x0(0)/0x0(0) Next 0x0(0)/0x0(0)/0x0(0) Last retransmission scan length is 1, maximum is 1 Last retransmission scan time is 0 msec, maximum is 0 msec
What does this output indicate?
A network engineer runs the following command to verify OSPF SPF calculations:
R1# show ip ospf statistics
OSPF Router with ID (1.1.1.1) (Process ID 1)
Area 0: SPF algorithm executed 12 times
SPF calculation time (in msec): Total: 12, Average: 1.0 Minimum: 0, Maximum: 2 Last SPF due to: LSA change Number of LSA changes: 5 Number of LSA deletions: 2 Number of LSA additions: 3 Number of LSA updates: 0
Area 1: SPF algorithm executed 3 times
SPF calculation time (in msec): Total: 3, Average: 1.0 Minimum: 0, Maximum: 1 Last SPF due to: LSA change Number of LSA changes: 2 Number of LSA deletions: 0 Number of LSA additions: 2 Number of LSA updates: 0
What does this output indicate?
A network engineer runs the following command to troubleshoot OSPF route installation:
R1# show ip route ospf
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, H - NHRP, l - LISP a - application route + - replicated route, % - next hop override
Gateway of last resort is not set
O 10.1.1.0/24 [110/10] via 10.1.1.2, 00:12:34, GigabitEthernet0/0
O IA 192.168.1.0/24 [110/20] via 10.1.1.2, 00:10:00, GigabitEthernet0/0 O E2 5.5.5.5/32 [110/20] via 10.1.1.2, 00:05:00, GigabitEthernet0/0
What does this output indicate?