Route Redistribution practice questions

A network engineer is troubleshooting a route redistribution issue between OSPF and EIGRP. Routers R1 (OSPF) and R2 (EIGRP) are redistributing routes into each other. The engineer notices that some OSPF external routes are not appearing in the EIGRP topology table on R2, although the redistribution is configured. The show ip eigrp topology command on R2 does not list the missing prefixes. What is the most likely cause?

Trap 1: The redistribute ospf command under EIGRP is missing the match…

The match internal keyword is the default and includes OSPF internal routes, but external routes require match external.

Trap 2: The OSPF process on R1 has a route filter blocking external routes.

The issue is on the redistributing router (R2), not on R1.

Trap 3: EIGRP has a lower administrative distance than OSPF, causing route…

Administrative distance affects route selection, not redistribution of specific route types.

A
The redistribute ospf command under EIGRP is missing the match internal keyword.
Why wrong: The match internal keyword is the default and includes OSPF internal routes, but external routes require match external.
B
The redistribute ospf command under EIGRP is missing the match external keyword.
Correct: Without match external, OSPF external routes are not redistributed into EIGRP.
C
The OSPF process on R1 has a route filter blocking external routes.
Why wrong: The issue is on the redistributing router (R2), not on R1.
D
EIGRP has a lower administrative distance than OSPF, causing route suppression.
Why wrong: Administrative distance affects route selection, not redistribution of specific route types.

Question 2mediummultiple choice

A network engineer is troubleshooting a route redistribution issue between EIGRP and OSPF. Routers R1 (EIGRP) and R2 (OSPF) are redistributing routes. The engineer notices that some EIGRP external routes (redistributed into EIGRP from another protocol) are not appearing in the OSPF database on R2. The show ip ospf database external command on R2 does not list these prefixes. What is the most likely cause?

Trap 1: The redistribute eigrp command under OSPF is missing the subnets…

The subnets keyword is needed for classless routes, but the issue here is about external routes, not subnetting.

Trap 2: EIGRP has a higher administrative distance than OSPF, causing route…

Administrative distance affects route selection, not redistribution of specific route types.

Trap 3: The OSPF process on R2 has a distribute-list blocking these routes.

While possible, the default behavior of not redistributing external routes is a more common and likely cause.

A
The redistribute eigrp command under OSPF is missing the subnets keyword.
Why wrong: The subnets keyword is needed for classless routes, but the issue here is about external routes, not subnetting.
B
The redistribute eigrp command under OSPF is missing the match external keyword.
Correct: Without match external, EIGRP external routes are not redistributed into OSPF.
C
EIGRP has a higher administrative distance than OSPF, causing route suppression.
Why wrong: Administrative distance affects route selection, not redistribution of specific route types.
D
The OSPF process on R2 has a distribute-list blocking these routes.
Why wrong: While possible, the default behavior of not redistributing external routes is a more common and likely cause.

Question 3hardmultiple choice

A network engineer is troubleshooting a route redistribution issue between two OSPF processes. Router R1 runs OSPF process 1 and OSPF process 2, and redistributes routes between them. The engineer notices that routes from OSPF process 1 are not appearing in the OSPF database of process 2, even though the redistribute command is configured. The show ip ospf database command on R1 for process 2 shows no external routes. What is the most likely cause?

Trap 1: OSPF process 1 has a higher administrative distance than OSPF…

Administrative distance is not relevant when redistributing between processes on the same router.

Trap 2: The redistribute ospf 1 command under OSPF process 2 is missing the…

Redistribution between OSPF processes includes all routes by default; match internal is not applicable here.

Trap 3: OSPF process 2 has a route map applied that is filtering all routes.

While possible, the missing subnets keyword is a more common and likely cause.

A
The redistribute ospf 1 command under OSPF process 2 is missing the subnets keyword.
Correct: Without subnets, only classful networks are redistributed, causing many missing routes.
B
OSPF process 1 has a higher administrative distance than OSPF process 2.
Why wrong: Administrative distance is not relevant when redistributing between processes on the same router.
C
The redistribute ospf 1 command under OSPF process 2 is missing the match internal keyword.
Why wrong: Redistribution between OSPF processes includes all routes by default; match internal is not applicable here.
D
OSPF process 2 has a route map applied that is filtering all routes.
Why wrong: While possible, the missing subnets keyword is a more common and likely cause.

Question 4mediummultiple choice

A network engineer is troubleshooting a route redistribution issue between RIP and OSPF. Router R1 runs both RIP and OSPF, and redistributes RIP routes into OSPF. The engineer notices that RIP routes are not appearing in the OSPF database on neighboring routers. The show ip ospf database external command on a neighbor shows no external routes from R1. The redistribute rip command is configured under OSPF on R1. What is the most likely cause?

Trap 1: RIP has a higher administrative distance than OSPF.

Administrative distance affects route selection, not redistribution.

Trap 2: The OSPF process on R1 has a distribute-list blocking these routes.

While possible, the missing subnets keyword is a more common and likely cause.

Trap 3: The RIP process on R1 is not running.

If RIP were not running, no routes would be redistributed, but the engineer would likely see other symptoms.

A
The redistribute rip command under OSPF is missing the subnets keyword.
Correct: Without subnets, only classful networks are redistributed, causing missing routes.
B
RIP has a higher administrative distance than OSPF.
Why wrong: Administrative distance affects route selection, not redistribution.
C
The OSPF process on R1 has a distribute-list blocking these routes.
Why wrong: While possible, the missing subnets keyword is a more common and likely cause.
D
The RIP process on R1 is not running.
Why wrong: If RIP were not running, no routes would be redistributed, but the engineer would likely see other symptoms.

Open the full BGP breakdown →

Question 5hardmultiple choice

A network engineer is troubleshooting a route redistribution issue between EIGRP and BGP. Router R1 runs both EIGRP and BGP, and redistributes EIGRP routes into BGP. The engineer notices that some EIGRP routes are not appearing in the BGP table on R1. The show ip bgp command does not list these prefixes. The redistribute eigrp command is configured under BGP. What is the most likely cause?

Trap 1: The redistribute eigrp command under BGP is missing the subnets…

While subnets is important, the more likely cause is that the routes are not in the routing table.

Trap 2: BGP has a higher administrative distance than EIGRP.

Administrative distance affects route selection, not redistribution.

Trap 3: The EIGRP process on R1 has a route filter blocking these routes.

If routes are filtered in EIGRP, they would not be in the routing table, but the question asks for the most likely cause.

A
The redistribute eigrp command under BGP is missing the subnets keyword.
Why wrong: While subnets is important, the more likely cause is that the routes are not in the routing table.
B
The EIGRP routes are not present in the IP routing table on R1.
Correct: BGP only redistributes routes that are in the routing table; if they are missing, redistribution fails.
C
BGP has a higher administrative distance than EIGRP.
Why wrong: Administrative distance affects route selection, not redistribution.
D
The EIGRP process on R1 has a route filter blocking these routes.
Why wrong: If routes are filtered in EIGRP, they would not be in the routing table, but the question asks for the most likely cause.

Question 6hardmultiple choice

A network engineer is troubleshooting a route redistribution issue between OSPF and BGP. Router R1 runs both OSPF and BGP, and redistributes OSPF routes into BGP. The engineer notices that OSPF external routes are not appearing in the BGP table on R1. The show ip bgp command does not list these prefixes. The redistribute ospf 1 match external command is configured under BGP. What is the most likely cause?

Trap 1: OSPF has a higher administrative distance than BGP.

Administrative distance affects route selection, not redistribution.

Trap 2: The OSPF process on R1 has a distribute-list blocking these routes.

While possible, the missing subnets keyword is a more common and likely cause.

Trap 3: BGP requires the network command to advertise routes, not…

Redistribution is a valid method to inject routes into BGP.

A
The redistribute ospf 1 match external command under BGP is missing the subnets keyword.
Correct: Without subnets, only classful networks are redistributed, causing missing routes.
B
OSPF has a higher administrative distance than BGP.
Why wrong: Administrative distance affects route selection, not redistribution.
C
The OSPF process on R1 has a distribute-list blocking these routes.
Why wrong: While possible, the missing subnets keyword is a more common and likely cause.
D
BGP requires the network command to advertise routes, not redistribution.
Why wrong: Redistribution is a valid method to inject routes into BGP.

Question 7mediummultiple choice

A network engineer is troubleshooting a route redistribution issue between EIGRP and OSPF. Routers R1 (EIGRP) and R2 (OSPF) are redistributing routes. The engineer notices that some EIGRP routes are appearing in the OSPF database on R2, but traffic to those destinations is not being forwarded correctly. The show ip route command on R2 shows the redistributed routes with a next-hop of 0.0.0.0. What is the most likely cause?

Trap 1: The OSPF process on R2 has a route map that is changing the…

While possible, the missing subnets keyword is a more common and likely cause.

Trap 2: EIGRP has a lower administrative distance than OSPF.

Administrative distance affects route selection, not next-hop behavior.

Trap 3: The EIGRP routes are not in the routing table on R2.

If they were not in the routing table, they would not be redistributed.

A
The redistribute eigrp command under OSPF is missing the subnets keyword.
Correct: Without subnets, the next-hop may be set to 0.0.0.0 for classless routes.
B
The OSPF process on R2 has a route map that is changing the next-hop.
Why wrong: While possible, the missing subnets keyword is a more common and likely cause.
C
EIGRP has a lower administrative distance than OSPF.
Why wrong: Administrative distance affects route selection, not next-hop behavior.
D
The EIGRP routes are not in the routing table on R2.
Why wrong: If they were not in the routing table, they would not be redistributed.

Question 8hardmultiple choice

A network engineer is troubleshooting a route redistribution issue between OSPF and EIGRP. Routers R1 (OSPF) and R2 (EIGRP) are redistributing routes. The engineer notices that some OSPF routes are appearing in the EIGRP topology table on R2, but traffic to those destinations is being dropped. The show ip route command on R2 shows the redistributed routes with a next-hop of the R1 interface, but the route is not installed in the routing table. What is the most likely cause?

Trap 1: OSPF has a higher administrative distance than EIGRP.

Administrative distance affects route selection, but the route is not installed at all.

Trap 2: The EIGRP process on R2 has a distribute-list blocking these routes.

If a distribute-list were blocking, the routes would not appear in the topology table.

Trap 3: The OSPF process on R1 has a route filter blocking these routes.

The issue is on R2, not R1.

A
The redistribute ospf command under EIGRP is missing the default-metric configuration.
Correct: Without a default-metric, EIGRP may not install redistributed routes if the metric is not set properly.
B
OSPF has a higher administrative distance than EIGRP.
Why wrong: Administrative distance affects route selection, but the route is not installed at all.
C
The EIGRP process on R2 has a distribute-list blocking these routes.
Why wrong: If a distribute-list were blocking, the routes would not appear in the topology table.
D
The OSPF process on R1 has a route filter blocking these routes.
Why wrong: The issue is on R2, not R1.

Question 9mediummultiple choice

A network engineer is troubleshooting a route redistribution issue between two EIGRP processes. Router R1 runs EIGRP AS 100 and EIGRP AS 200, and redistributes routes between them. The engineer notices that routes from EIGRP AS 100 are not appearing in the EIGRP topology table of AS 200 on R1. The redistribute eigrp 100 command is configured under EIGRP AS 200. What is the most likely cause?

Trap 1: EIGRP AS 100 has a higher administrative distance than EIGRP AS 200.

Administrative distance is not relevant when redistributing between processes on the same router.

Trap 2: The redistribute eigrp 100 command under EIGRP AS 200 is missing…

The subnets keyword is not used in EIGRP redistribution.

Trap 3: EIGRP AS 200 has a route map that is filtering all routes.

While possible, the missing metric is a more common and likely cause.

A
The redistribute eigrp 100 command under EIGRP AS 200 is missing the metric specification.
Correct: Without a metric, EIGRP does not accept redistributed routes.
B
EIGRP AS 100 has a higher administrative distance than EIGRP AS 200.
Why wrong: Administrative distance is not relevant when redistributing between processes on the same router.
C
The redistribute eigrp 100 command under EIGRP AS 200 is missing the subnets keyword.
Why wrong: The subnets keyword is not used in EIGRP redistribution.
D
EIGRP AS 200 has a route map that is filtering all routes.
Why wrong: While possible, the missing metric is a more common and likely cause.

Question 10mediummultiple choice

A network engineer runs the following command on Router R1:

R1# show ip eigrp topology 10.1.1.0/24

IP-EIGRP (AS 100): Topology entry for 10.1.1.0/24 State: Passive, Originating reply status: 0 Routing Descriptor Blocks:

0.0.0.0 (Null0), from 0.0.0.0, Send flag: 0x0

Composite metric is (2560000000/0), Route is Internal Vector metric: Minimum bandwidth is 100000 Kbit Total delay is 100 microseconds Reliability is 255/255 Load is 1/255 Minimum MTU is 1500 Hop count is 0

10.2.2.2 (GigabitEthernet0/1), from 10.2.2.2, Send flag: 0x0

Composite metric is (2688000000/2560000000), Route is Internal Vector metric: Minimum bandwidth is 100000 Kbit Total delay is 200 microseconds Reliability is 255/255 Load is 1/255 Minimum MTU is 1500 Hop count is 1

Based on this output, what is the problem?

Trap 1: The route 10.1.1.0/24 is redistributed from another protocol into…

The route is marked as Internal, not External, so it is not redistributed.

Trap 2: The route 10.1.1.0/24 is flapping between Passive and Active states.

The state is Passive, indicating stability, not flapping.

Trap 3: The neighbor 10.2.2.2 is not reachable, so the route is installed…

The neighbor is reachable as shown by the Routing Descriptor Block, and the Null0 entry is for the summary, not due to unreachability.

A
The route 10.1.1.0/24 is redistributed from another protocol into EIGRP.
Why wrong: The route is marked as Internal, not External, so it is not redistributed.
B
A manual summary route is configured on R1 for 10.1.1.0/24, causing a local Null0 entry.
The Null0 entry with metric 2560000000/0 indicates a summary route; the 'ip summary-address eigrp' command creates this entry to prevent loops.
C
The route 10.1.1.0/24 is flapping between Passive and Active states.
Why wrong: The state is Passive, indicating stability, not flapping.
D
The neighbor 10.2.2.2 is not reachable, so the route is installed via Null0.
Why wrong: The neighbor is reachable as shown by the Routing Descriptor Block, and the Null0 entry is for the summary, not due to unreachability.

Question 11mediummultiple choice

A network engineer runs the following command on Router R1:

R1# show ip ospf database external 10.1.1.0

OSPF Router with ID (1.1.1.1) (Process ID 1)

Type-5 AS External Link States (Area 0)

LS age: 120 Options: (No TOS-capability, DC) LS Type: AS External Link Link State ID: 10.1.1.0 (External Network Number) Advertising Router: 2.2.2.2 LS Seq Number: 80000001 Checksum: 0x1234 Length: 36 Network Mask: /24 Metric Type: 2 (Larger than any link state path) TOS: 0 Metric: 20 Forward Address: 0.0.0.0 External Route Tag: 100

Based on this output, which statement is correct?

Trap 1: The route 10.1.1.0/24 is an OSPF inter-area route from area 0.

This is a Type-5 LSA, which is external, not inter-area (Type-3).

Trap 2: The metric of 20 indicates the route is redistributed with a…

Metric Type 2 is default; Type 1 would have metric-type 1. The metric 20 is default for Type 2.

Trap 3: The forward address of 0.0.0.0 indicates that the next hop is the…

Forward address 0.0.0.0 means the next hop is the advertising router itself, but this is a standard behavior, not a problem.

A
The route 10.1.1.0/24 is redistributed into OSPF from another protocol with a route-map setting the tag to 100.
The External Route Tag of 100 is a common indicator that a route-map was used during redistribution to set the tag.
B
The route 10.1.1.0/24 is an OSPF inter-area route from area 0.
Why wrong: This is a Type-5 LSA, which is external, not inter-area (Type-3).
C
The metric of 20 indicates the route is redistributed with a default metric of 20, which is correct for Type 1 external routes.
Why wrong: Metric Type 2 is default; Type 1 would have metric-type 1. The metric 20 is default for Type 2.
D
The forward address of 0.0.0.0 indicates that the next hop is the advertising router 2.2.2.2.
Why wrong: Forward address 0.0.0.0 means the next hop is the advertising router itself, but this is a standard behavior, not a problem.

Open the full BGP breakdown →

Question 12mediummultiple choice

A network engineer runs the following command on Router R1:

R1# show ip bgp 10.1.1.0/24

BGP routing table entry for 10.1.1.0/24, version 10 Paths: (1 available, best #1, table default) Advertised to update-groups: 1 Refresh Epoch 1 Local

10.2.2.2 from 10.2.2.2 (2.2.2.2)

Origin IGP, metric 0, localpref 100, valid, external, best rx pathid: 0, tx pathid: 0x0 Community: 100:200

Based on this output, what is the problem?

Trap 1: The route 10.1.1.0/24 is learned via an eBGP session and has a…

The route is marked as 'Local', meaning it was redistributed from an IGP, not learned via eBGP.

Trap 2: The community 100:200 is automatically assigned by BGP for all…

Communities are not automatically assigned; they must be configured via route-maps.

Trap 3: The route is not being advertised to any peers because it is not…

The route is marked as best, so it is advertised.

A
The route 10.1.1.0/24 is learned via an eBGP session and has a local preference of 100.
Why wrong: The route is marked as 'Local', meaning it was redistributed from an IGP, not learned via eBGP.
B
The route 10.1.1.0/24 is redistributed from an IGP into BGP, as indicated by the 'Local' path.
The 'Local' path attribute in BGP indicates the route was originated locally via network statement or redistribution from an IGP.
C
The community 100:200 is automatically assigned by BGP for all redistributed routes.
Why wrong: Communities are not automatically assigned; they must be configured via route-maps.
D
The route is not being advertised to any peers because it is not marked as best.
Why wrong: The route is marked as best, so it is advertised.

Question 13hardmultiple choice

A network engineer runs the following command on Router R1:

R1# show route-map REDISTRIBUTE

route-map REDISTRIBUTE, permit, sequence 10 Match clauses:

ip address prefix-list EIGRP_ROUTES

Set clauses: metric 100 metric-type type-1 tag 200 Policy routing matches: 0 packets, 0 bytes

route-map REDISTRIBUTE, deny, sequence 20 Match clauses:

ip address prefix-list DENY_ALL

Set clauses: Policy routing matches: 0 packets, 0 bytes

Based on this output, what is the problem?

Trap 1: The route-map will redistribute all routes that match prefix-list…

While sequence 10 permits matching routes, sequence 20 denies all routes if DENY_ALL matches everything, so redistribution may fail.

Trap 2: The route-map will only redistribute routes with tag 200.

The tag is set, not matched; redistribution is based on match clauses, not set clauses.

Trap 3: The route-map is not applied to any redistribution command, so it…

The output shows the route-map is defined, but we don't know if it is applied; however, the question is about the route-map itself.

A
The route-map will redistribute all routes that match prefix-list EIGRP_ROUTES with metric 100 and type-1.
Why wrong: While sequence 10 permits matching routes, sequence 20 denies all routes if DENY_ALL matches everything, so redistribution may fail.
B
The route-map has a deny sequence that may block all routes if prefix-list DENY_ALL is configured to permit all.
If DENY_ALL is a catch-all prefix-list (e.g., permit 0.0.0.0/0 le 32), then sequence 20 will deny all routes, overriding sequence 10.
C
The route-map will only redistribute routes with tag 200.
Why wrong: The tag is set, not matched; redistribution is based on match clauses, not set clauses.
D
The route-map is not applied to any redistribution command, so it has no effect.
Why wrong: The output shows the route-map is defined, but we don't know if it is applied; however, the question is about the route-map itself.

Question 14mediummultiple choice

A network engineer runs the following command on Router R1:

R1# show ip route 10.1.1.0

Routing entry for 10.1.1.0/24 Known via "eigrp 100", distance 170, metric 2560000 Redistributing via eigrp 100 Advertised by eigrp 100 (self originated) Last update from 10.2.2.2 on GigabitEthernet0/1, 00:00:10 ago Routing Descriptor Blocks:

* 10.2.2.2, from 10.2.2.2, 00:00:10 ago, via GigabitEthernet0/1

Route metric is 2560000, traffic share count is 1 Total delay is 100 microseconds, minimum bandwidth is 100000 Kbit Reliability 255/255, minimum MTU 1500 Loading 1/255, Hops 1

Based on this output, what is the problem?

Trap 1: The route 10.1.1.0/24 is an internal EIGRP route because the…

The distance is 170, which is for external EIGRP routes.

Trap 2: The route is learned from a neighbor with a metric of 2560000,…

The metric is 2560000, but it is not necessarily the default; it is the metric set during redistribution.

Trap 3: The route is not being advertised to any EIGRP neighbors because it…

The 'self originated' flag means the router originated the route, but it can still be advertised to neighbors.

A
The route 10.1.1.0/24 is an internal EIGRP route because the administrative distance is 90.
Why wrong: The distance is 170, which is for external EIGRP routes.
B
The route is redistributed into EIGRP from another protocol, as indicated by the distance of 170 and the 'self originated' message.
The distance of 170 and the 'self originated' flag indicate redistribution into EIGRP.
C
The route is learned from a neighbor with a metric of 2560000, which is the default for redistributed routes.
Why wrong: The metric is 2560000, but it is not necessarily the default; it is the metric set during redistribution.
D
The route is not being advertised to any EIGRP neighbors because it is marked as 'self originated'.
Why wrong: The 'self originated' flag means the router originated the route, but it can still be advertised to neighbors.

Question 15mediummultiple choice

A network engineer runs the following command on Router R1:

R1# show ip ospf interface GigabitEthernet0/1

GigabitEthernet0/1 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: 1 Transmit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) 1.1.1.1, Interface address 10.1.1.1 Backup Designated router (ID) 2.2.2.2, Interface address 10.1.1.2 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 Index 1/1, flood queue length 0 Next 0x0(0)/0x0(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 (Backup Designated Router) Suppress hello for 0 neighbor(s)

Based on this output, what is the problem?

Trap 1: The router is the DR, which is normal, but the neighbor count of 1…

This is a normal state; no problem is indicated.

Trap 2: The interface is in area 0, but redistribution of external routes…

Redistribution does not require a route-map; it can be done with default metrics.

Trap 3: The router ID is 1.1.1.1, which is not reachable from other routers.

The router ID is an IP address used for OSPF, but reachability is not an issue here.

A
The router is the DR, which is normal, but the neighbor count of 1 indicates only one OSPF neighbor is present.
Why wrong: This is a normal state; no problem is indicated.
B
The interface is in area 0, but redistribution of external routes requires a route-map to set the metric.
Why wrong: Redistribution does not require a route-map; it can be done with default metrics.
C
The output shows no external routes are being redistributed, but this is a normal interface status.
The interface output is normal; redistribution status is not shown here. The candidate must understand that this command does not show redistribution information.
D
The router ID is 1.1.1.1, which is not reachable from other routers.
Why wrong: The router ID is an IP address used for OSPF, but reachability is not an issue here.

Open the full BGP breakdown →

Question 16hardmultiple choice

A network engineer runs the following command on Router R1:

R1# show ip bgp neighbors 10.2.2.2 advertised-routes

BGP table version is 10, local router ID is 1.1.1.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path *> 10.1.1.0/24 0.0.0.0 0 32768 i *> 10.2.2.0/24 0.0.0.0 0 32768 i

Total number of prefixes 2

Based on this output, what is the problem?

Trap 1: The routes are correctly advertised with next hop 0.0.0.0, which is…

Next hop 0.0.0.0 is used in the BGP table for locally originated routes, but when advertised to eBGP peers, the next hop should be changed to the router's interface IP.

Trap 2: The routes are being advertised to iBGP peers only, as indicated by…

The next hop 0.0.0.0 is used in the local BGP table, not specifically for iBGP.

Trap 3: The routes are redistributed from an IGP into BGP, and the next hop…

Redistributed routes also have next hop 0.0.0.0 locally, but this is not correct for eBGP advertisements.

A
The routes are correctly advertised with next hop 0.0.0.0, which is normal for locally originated routes.
Why wrong: Next hop 0.0.0.0 is used in the BGP table for locally originated routes, but when advertised to eBGP peers, the next hop should be changed to the router's interface IP.
B
The routes are not being advertised to eBGP peers because the next hop is 0.0.0.0, which is invalid for eBGP.
For eBGP, the next hop must be reachable; 0.0.0.0 is not a valid next hop for eBGP advertisements, so the routes may not be installed by the peer.
C
The routes are being advertised to iBGP peers only, as indicated by the next hop 0.0.0.0.
Why wrong: The next hop 0.0.0.0 is used in the local BGP table, not specifically for iBGP.
D
The routes are redistributed from an IGP into BGP, and the next hop is correctly set to 0.0.0.0.
Why wrong: Redistributed routes also have next hop 0.0.0.0 locally, but this is not correct for eBGP advertisements.

Question 17mediummultiple choice

A network engineer runs the following command on Router R1:

R1# show ip eigrp interfaces detail GigabitEthernet0/1

IP-EIGRP interfaces for process 100

Xmit Queue Mean Pacing Time Multicast Pending

Interface        Peers  Un/Reliable  SRTT   Un/Reliable   Flow Timer   Routes

Gi0/1 1 0/0 10 0/10 50 0 Hello interval is 5 sec Next xmit serial <none> Un/reliable mcasts: 0/0 Un/reliable ucasts: 0/0 Mcast exceptions: 0 CR packets: 0 ACKs suppressed: 0 Retransmissions: 0 Out of sequence: 0 Authentication mode: none Redistribution: redistributed

Based on this output, what is the problem?

Trap 1: The interface is configured for redistribution, which is correct…

EIGRP redistribution is configured globally under the EIGRP process, not per interface.

Trap 2: The interface has one EIGRP neighbor, and redistribution is working…

The neighbor count is normal, but redistribution is not an interface-level feature.

Trap 3: The output shows that redistribution is enabled, but the interface…

The hello interval is shown, so hellos are being sent.

A
The interface is configured for redistribution, which is correct for EIGRP.
Why wrong: EIGRP redistribution is configured globally under the EIGRP process, not per interface.
B
The 'redistributed' flag indicates that routes are being redistributed into EIGRP on this interface, which is not a standard EIGRP feature.
EIGRP does not have per-interface redistribution; this output is likely from a different context or a misinterpretation.
C
The interface has one EIGRP neighbor, and redistribution is working correctly.
Why wrong: The neighbor count is normal, but redistribution is not an interface-level feature.
D
The output shows that redistribution is enabled, but the interface is not sending hellos.
Why wrong: The hello interval is shown, so hellos are being sent.

Question 18mediummultiple choice

A network engineer runs the following command on Router R1:

R1# show ip route 192.168.1.0

Routing entry for 192.168.1.0/24 Known via "ospf 1", distance 110, metric 20, type extern 2, forward metric 100 Redistributing via ospf 1 Last update from 10.1.1.2 on GigabitEthernet0/1, 00:00:05 ago Routing Descriptor Blocks:

* 10.1.1.2, from 10.1.1.2, 00:00:05 ago, via GigabitEthernet0/1

Route metric is 20, traffic share count is 1

Based on this output, what is the problem?

Trap 1: The route is an external OSPF route with metric 20, which is the…

This is correct, but not a problem.

Trap 2: The forward metric is 100, which is the metric to the ASBR.

The forward metric is normal for external routes.

Trap 3: The route is learned from neighbor 10.1.1.2, which is the next hop.

This is normal.

A
The route is an external OSPF route with metric 20, which is the default for Type 2 external routes.
Why wrong: This is correct, but not a problem.
B
The route is being redistributed back into OSPF, which could cause a routing loop if not filtered.
Redistributing a route learned from OSPF back into OSPF without filtering can cause loops.
C
The forward metric is 100, which is the metric to the ASBR.
Why wrong: The forward metric is normal for external routes.
D
The route is learned from neighbor 10.1.1.2, which is the next hop.
Why wrong: This is normal.

Question 19mediummultiple choice

Consider the following partial configuration on Router R1:

router eigrp 100

redistribute ospf 1 metric 10000 100 255 1 1500

router ospf 1

redistribute eigrp 100 subnets

Which statement about this configuration is true?

Trap 1: OSPF routes redistributed into EIGRP will have a metric of 20 by…

The default metric for OSPF redistribution into EIGRP is not defined; the 'metric' keyword is required or a default-metric command must be used.

Trap 2: EIGRP routes redistributed into OSPF will be Type 1 external LSAs.

By default, redistributed routes into OSPF are Type 2 external LSAs unless the 'metric-type' keyword is used.

Trap 3: The 'subnets' keyword in OSPF redistribution is optional but…

Without 'subnets', only classful networks are redistributed, which is often not desired. The 'subnets' keyword is not optional if you want all prefixes.

A
Redistributed OSPF routes into EIGRP will have a default metric of 10000 100 255 1 1500.
The 'metric' keyword in the redistribute command sets the EIGRP metric for all redistributed routes.
B
OSPF routes redistributed into EIGRP will have a metric of 20 by default.
Why wrong: The default metric for OSPF redistribution into EIGRP is not defined; the 'metric' keyword is required or a default-metric command must be used.
C
EIGRP routes redistributed into OSPF will be Type 1 external LSAs.
Why wrong: By default, redistributed routes into OSPF are Type 2 external LSAs unless the 'metric-type' keyword is used.
D
The 'subnets' keyword in OSPF redistribution is optional but recommended.
Why wrong: Without 'subnets', only classful networks are redistributed, which is often not desired. The 'subnets' keyword is not optional if you want all prefixes.

Question 20mediummultiple choice

Given the following configuration on Router R2:

router eigrp 200

redistribute ospf 1 metric 10000 100 255 1 1500 default-metric 10000 100 255 1 1500

What is the effect of having both the 'metric' keyword in the redistribute command and the 'default-metric' command?

Trap 1: The 'metric' keyword is ignored; the default-metric is used for all…

The explicit metric in the redistribute command takes precedence over the default-metric.

Trap 2: Both metrics are applied, causing a conflict and potential routing…

There is no conflict; the redistribute command metric overrides the default-metric for that specific redistribution.

Trap 3: The default-metric command is not needed and can be removed without…

The default-metric is still useful for other redistribution sources that do not have an explicit metric.

A
The 'metric' keyword is ignored; the default-metric is used for all redistributed routes.
Why wrong: The explicit metric in the redistribute command takes precedence over the default-metric.
B
Both metrics are applied, causing a conflict and potential routing issues.
Why wrong: There is no conflict; the redistribute command metric overrides the default-metric for that specific redistribution.
C
The 'metric' keyword overrides the default-metric for routes redistributed from OSPF into EIGRP.
The explicit metric in the redistribute command takes precedence over the default-metric.
D
The default-metric command is not needed and can be removed without any effect.
Why wrong: The default-metric is still useful for other redistribution sources that do not have an explicit metric.