Eigrp practice questions

A network engineer is configuring EIGRP on a router that connects to a service provider network. The engineer wants to advertise a default route to internal routers. The engineer configures 'ip default-network 0.0.0.0' and redistributes a static default route into EIGRP. However, internal routers are not receiving the default route. The engineer checks the EIGRP topology table and sees the default route with a metric of 1. What is the most likely reason?

Trap 1: The engineer used 'ip default-network' which is not supported in…

Ly states that 'default-information originate' should be used for EIGRP. That command is for OSPF, not EIGRP. While 'ip default-network' is indeed not supported in EIGRP, the correct method is to redistribute a properly configured static default route, not to use 'default-information originate'. Therefore, this is not the most likely reason.

Trap 2: The internal routers have a route to the default network with a…

Internal routers are not receiving the default route at all, so they cannot have a route with a better metric from another source. This option describes a scenario where the route is received but not preferred, which does not match the problem.

Trap 3: The engineer needs to configure 'eigrp stub' on the router to allow…

Configuring 'eigrp stub' on the router would restrict route advertisement, not allow it. To advertise a default route from a stub router, you would need the 'summary' keyword, but the router is not necessarily a stub. This would not be the most likely reason for the failure.

A
The engineer used 'ip default-network' which is not supported in EIGRP; instead, 'default-information originate' should be used.
Why wrong: Ly states that 'default-information originate' should be used for EIGRP. That command is for OSPF, not EIGRP. While 'ip default-network' is indeed not supported in EIGRP, the correct method is to redistribute a properly configured static default route, not to use 'default-information originate'. Therefore, this is not the most likely reason.
B
The static default route is not configured correctly; the engineer should use 'ip route 0.0.0.0 0.0.0.0 <next-hop>'.
Correct. The static default route must be correctly configured with a next-hop IP address. If the static route is missing or uses an interface instead of a next-hop, it may not be valid, and the redistribution will not propagate the route to internal routers, despite appearing in the topology table with a metric.
C
The internal routers have a route to the default network with a better metric from another source.
Why wrong: Internal routers are not receiving the default route at all, so they cannot have a route with a better metric from another source. This option describes a scenario where the route is received but not preferred, which does not match the problem.
D
The engineer needs to configure 'eigrp stub' on the router to allow default route advertisement.
Why wrong: Configuring 'eigrp stub' on the router would restrict route advertisement, not allow it. To advertise a default route from a stub router, you would need the 'summary' keyword, but the router is not necessarily a stub. This would not be the most likely reason for the failure.

Question 2mediummultiple choice

Examine the following EIGRP configuration on a Cisco IOS-XE device:

router eigrp 100
 network 10.0.0.0 0.255.255.255
 passive-interface default
 no passive-interface GigabitEthernet0/0

interface GigabitEthernet0/0
 ip address 10.1.1.1 255.255.255.0

interface GigabitEthernet0/1
 ip address 10.2.2.1 255.255.255.0

Which statement is true?

Trap 1: EIGRP will form adjacencies on both GigabitEthernet0/0 and…

Incorrect. Only GigabitEthernet0/0 is explicitly set to not be passive. GigabitEthernet0/1 remains passive and will not form adjacencies.

Trap 2: EIGRP will not form any adjacencies because the network command…

Incorrect. The network 10.0.0.0 0.255.255.255 matches both interfaces (10.1.1.1 and 10.2.2.1).

Trap 3: EIGRP will form adjacencies on all interfaces except those with…

Incorrect. The 'passive-interface default' makes all interfaces passive unless overridden with 'no passive-interface'.

A
EIGRP will form adjacencies on both GigabitEthernet0/0 and GigabitEthernet0/1.
Why wrong: Incorrect. Only GigabitEthernet0/0 is explicitly set to not be passive. GigabitEthernet0/1 remains passive and will not form adjacencies.
B
EIGRP will form an adjacency only on GigabitEthernet0/0.
Correct. GigabitEthernet0/0 is not passive, so it will send and receive hellos. GigabitEthernet0/1 is passive by default.
C
EIGRP will not form any adjacencies because the network command does not match the interface subnets.
Why wrong: Incorrect. The network 10.0.0.0 0.255.255.255 matches both interfaces (10.1.1.1 and 10.2.2.1).
D
EIGRP will form adjacencies on all interfaces except those with 'passive-interface' configured.
Why wrong: Incorrect. The 'passive-interface default' makes all interfaces passive unless overridden with 'no passive-interface'.

Question 3mediumdrag order

Drag and drop the steps of EIGRP stub configuration for hub-and-spoke into the correct order, from first to last.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 4mediumdrag order

Review the full OSPF breakdown →

Drag and drop the steps of EIGRP named mode configuration steps into the correct order, from first to last.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 5mediumdrag order

Drag and drop the steps of EIGRP redistribution from OSPF with metric seeding into the correct order, from first to last.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 6mediummatching

Drag and drop each EIGRP timer on the left to its matching default value on the right.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

5 seconds

15 seconds

3 minutes

0.5 seconds

Trap 1: Update Timer: 5 seconds

Incorrect: EIGRP does not have a standard 'Update Timer' with a default of 5 seconds. The 5-second default belongs to the Hello timer.

A
Hello Timer: 5 seconds
Correct: Hello timer default is 5 seconds on LAN.
B
Hold Timer: 15 seconds
Correct: Hold timer default is 15 seconds (3x Hello).
C
Active Timer: 3 minutes
Correct: Active timer default is 3 minutes.
D
Update Timer: 5 seconds
Why wrong: Incorrect: EIGRP does not have a standard 'Update Timer' with a default of 5 seconds. The 5-second default belongs to the Hello timer.
E
Retransmission Timer: 0.5 seconds
Correct: Retransmission timer default is 0.5 seconds.

Review the full OSPF breakdown →

Question 7mediumdrag order

Drag and drop the steps of OSPF redistribution from EIGRP with metric conversion into the correct order, from first to last.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 8easymatching

Drag and drop each protocol number on the left to its matching protocol on the right.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

Internet Control Message Protocol (ICMP)

Transmission Control Protocol (TCP)

User Datagram Protocol (UDP)

Open Shortest Path First (OSPF)

Enhanced Interior Gateway Routing Protocol (EIGRP)

Question 9mediumdrag order

Drag and drop the steps of EIGRP variance-based unequal-cost load balancing into the correct order, from first to last.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 10mediummultiple choice

Given the following configuration:

router eigrp TEST
 network 10.0.0.0 0.255.255.255
 network 192.168.1.0

interface GigabitEthernet0/0
 ip address 10.1.1.1 255.255.255.0
 ip summary-address eigrp TEST 10.0.0.0 255.0.0.0 5

What is the effect of the ip summary-address command?

Trap 1: It creates a summary route 10.0.0.0/8 with a metric of 5, but only…

The command is correct, but the metric value is actually the administrative distance, not the metric.

Trap 2: It creates a summary route 10.0.0.0/8 with a hop count of 5.

EIGRP does not use hop count; the value is the administrative distance.

Trap 3: The command is invalid because the summary address must match the…

The summary address can be a supernet of the network statement; this is valid.

A
It creates a summary route 10.0.0.0/8 with a metric of 5, advertised out GigabitEthernet0/0.
The summary address is 10.0.0.0/8, and the value 5 is the administrative distance for the summary route.
B
It creates a summary route 10.0.0.0/8 with a metric of 5, but only for the EIGRP process named TEST.
Why wrong: The command is correct, but the metric value is actually the administrative distance, not the metric.
C
It creates a summary route 10.0.0.0/8 with a hop count of 5.
Why wrong: EIGRP does not use hop count; the value is the administrative distance.
D
The command is invalid because the summary address must match the network statement exactly.
Why wrong: The summary address can be a supernet of the network statement; this is valid.

Question 11mediummatching

Drag and drop each EIGRP metric component on the left to its matching variable on the right.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

Bandwidth

Load

Delay

Reliability

Trap 1: K5: MTU

Incorrect: MTU is not a K variable in the EIGRP metric formula. It is only used in the feasibility condition.

A
K1: Bandwidth
Correct: K1 is bandwidth.
B
K2: Load
Correct: K2 is load.
C
K3: Delay
Correct: K3 is delay.
D
K4: Reliability
Correct: K4 is reliability.
E
K5: MTU
Why wrong: Incorrect: MTU is not a K variable in the EIGRP metric formula. It is only used in the feasibility condition.

Question 12hardmulti select

Which three statements about EIGRP stub routing are true? (Choose three.)

Trap 1: A hub router will send queries to a stub router when a route is…

Incorrect because the hub router does not send queries to a stub router, as the stub is not expected to have alternative paths.

Trap 2: Stub routing is used to reduce the size of the routing table on the…

Incorrect because stub routing primarily reduces query propagation and convergence time, not the routing table size on the hub.

A
A stub router does not send Query packets to its neighbors.
Correct because stub routers are not allowed to originate queries; they rely on the hub for routing information.
B
A hub router will send queries to a stub router when a route is lost.
Why wrong: Incorrect because the hub router does not send queries to a stub router, as the stub is not expected to have alternative paths.
C
The 'eigrp stub' command can be configured with the 'connected' keyword to advertise only connected routes.
Correct because the 'connected' keyword limits the stub to advertising only directly connected networks.
D
Stub routing is used to reduce the size of the routing table on the hub router.
Why wrong: Incorrect because stub routing primarily reduces query propagation and convergence time, not the routing table size on the hub.
E
A stub router can be configured as 'receive-only' to not advertise any routes.
Correct because the 'receive-only' keyword prevents the stub from advertising any routes; it only receives routes from the hub.

Question 13easymultiple choice

What is the maximum hop count for EIGRP?

Trap 1: 15

15 is the maximum hop count for RIP, not EIGRP.

Trap 2: 224

The value 224 is incorrect for EIGRP's maximum hop count, which is configurable up to 255, with a default of 100. This option is tempting because 224 relates to multicast IP addresses. EIGRP utilises the multicast address 224.0.0.10 to discover neighbours and exchange routing updates, a crucial operational aspect, but entirely separate from the metric used to determine path length.

Trap 3: Unlimited

EIGRP has a finite hop count limit of 255.

A
255
EIGRP's maximum hop count is 255, inherited from IGRP.
B
15
Why wrong: 15 is the maximum hop count for RIP, not EIGRP.
C
224
Why wrong: The value 224 is incorrect for EIGRP's maximum hop count, which is configurable up to 255, with a default of 100. This option is tempting because 224 relates to multicast IP addresses. EIGRP utilises the multicast address 224.0.0.10 to discover neighbours and exchange routing updates, a crucial operational aspect, but entirely separate from the metric used to determine path length.
D
Unlimited
Why wrong: EIGRP has a finite hop count limit of 255.

Question 14mediumdrag order

Drag and drop the steps of EIGRP route summarization configuration into the correct order, from first to last.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 15easymultiple choice

What is the maximum hop count for EIGRP?

Trap 1: 15

15 is the maximum hop count for RIP, not EIGRP.

Trap 2: 255

255 is the configurable maximum, but the default is 100.

Trap 3: Unlimited

EIGRP has a hop count limit, though it is high.

A
15
Why wrong: 15 is the maximum hop count for RIP, not EIGRP.
B
100
The default maximum hop count for EIGRP is 100.
C
255
Why wrong: 255 is the configurable maximum, but the default is 100.
D
Unlimited
Why wrong: EIGRP has a hop count limit, though it is high.

Question 16mediummultiple choice

A router has the following configuration snippet:

vrf definition RED rd 100:1 !

interface Loopback0
 ip vrf forwarding RED
 ip address 10.0.0.1 255.255.255.255

router eigrp 100

address-family ipv4 unicast vrf RED autonomous-system 100

network 10.0.0.1 0.0.0.0

What is the issue with this EIGRP configuration for VRF RED?

Trap 1: The 'network' command should use a wildcard mask of 0.0.0.255…

Incorrect. A host mask is valid for a loopback interface.

Trap 2: The VRF must be defined under 'router eigrp' globally before using…

Incorrect. The address-family vrf command is the correct method.

Trap 3: The loopback interface cannot be placed in a VRF because it is a…

Incorrect. Loopback interfaces can be placed in VRFs.

A
The EIGRP address-family is not activated because 'no shutdown' is missing under the address-family configuration.
Correct. EIGRP address-families require 'no shutdown' to start.
B
The 'network' command should use a wildcard mask of 0.0.0.255 instead of 0.0.0.0.
Why wrong: Incorrect. A host mask is valid for a loopback interface.
C
The VRF must be defined under 'router eigrp' globally before using address-family.
Why wrong: Incorrect. The address-family vrf command is the correct method.
D
The loopback interface cannot be placed in a VRF because it is a virtual interface.
Why wrong: Incorrect. Loopback interfaces can be placed in VRFs.

Review the full OSPF breakdown →

Question 17mediummultiple choice

An enterprise network uses OSPF as its IGP. The network engineer notices that a particular route learned via OSPF is not being installed in the routing table, even though the neighbor adjacency is up and the route appears in the OSPF database. The route is an external route redistributed from EIGRP. What is the most likely cause?

Trap 1: The OSPF process ID is different on the routers.

OSPF process IDs are locally significant and do not need to match between neighbours for adjacency formation or route exchange; the router ID, area configuration, and authentication parameters govern adjacency, not the process ID. This option is tempting because many routing protocols, such as EIGRP, require matching autonomous system numbers for neighbourship, so a candidate might incorrectly assume OSPF behaves identically.

Trap 2: The external route has a higher administrative distance than the…

Incorrect because administrative distance is used when comparing routes from different sources; the OSPF external route is not being installed at all, not being compared.

Trap 3: The OSPF metric for the external route is too high.

Incorrect because OSPF does not have a maximum metric that prevents route installation; even high metrics are installed.

A
The OSPF process ID is different on the routers.
Why wrong: OSPF process IDs are locally significant and do not need to match between neighbours for adjacency formation or route exchange; the router ID, area configuration, and authentication parameters govern adjacency, not the process ID. This option is tempting because many routing protocols, such as EIGRP, require matching autonomous system numbers for neighbourship, so a candidate might incorrectly assume OSPF behaves identically.
B
The external route has a higher administrative distance than the internal route.
Why wrong: Incorrect because administrative distance is used when comparing routes from different sources; the OSPF external route is not being installed at all, not being compared.
C
The forwarding address in the type 5 LSA is not reachable via an OSPF internal route.
Correct because OSPF requires the forwarding address to be reachable via an intra-area or inter-area route; otherwise, the external route is not installed.
D
The OSPF metric for the external route is too high.
Why wrong: Incorrect because OSPF does not have a maximum metric that prevents route installation; even high metrics are installed.

Question 18mediummatching

Drag and drop each EIGRP router role on the left to its matching definition on the right.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

Next-hop router with the lowest metric for a destination

Backup next-hop router meeting the feasibility condition

Directly connected EIGRP router exchanging Hello packets

Router is actively querying for a route

Router has a valid route and is not querying

Question 19mediumdrag order