CCNA IP Routing Practice Test 14 — 15 Questions

Question 1

A router receives a destination prefix from EIGRP with administrative distance 90 and also from OSPF with administrative distance 110. The prefix length is identical. Which route source is preferred?

Accepted Answer

EIGRP. The EIGRP route is preferred because its administrative distance is lower. In practical terms, once the prefix length is the same, the router compares the trustworthiness of the route source. Lower administrative distance wins. Since 90 is lower than 110, EIGRP is preferred over OSPF for that destination.

This is an administrative-distance comparison question, not a longest-prefix question. The key is that the prefix length is equal, so source preference becomes the deciding factor.

Answer

OSPF

Answer

Both equally

Answer

Neither, because route sources cannot overlap

Question 2

An OSPF router learns a route with metric 20 and another OSPF route to the same destination with metric 30. The prefix length is the same. Which path is preferred?

Accepted Answer

The route with metric 20. The OSPF path with metric 20 is preferred because, within the same routing protocol and for the same prefix length, the metric is used to compare candidate paths. In practical terms, the router is not comparing source trust here because both routes come from OSPF. It is comparing OSPF’s own internal path-cost values, and the lower metric wins.

This question is about separating administrative distance from metric. Since both routes come from the same protocol, metric is the deciding factor.

Answer

The route with metric 30

Answer

Both routes are rejected because the metrics differ

Answer

The default route is preferred

Question 3

Why is route summarization useful at a distribution layer or area boundary?

Accepted Answer

It reduces the number of specific prefixes that must be carried or advertised.. Route summarization is useful because it reduces the number of individual routes that have to be advertised and stored. In practical terms, one summary can represent many more specific internal prefixes, which helps keep routing tables smaller and updates simpler. That improves scalability and reduces control-plane clutter.

Summarization does not eliminate the need for detail everywhere, but it helps present the network more efficiently at aggregation points.

Answer

It forces all traffic to use a default route only.

Answer

It automatically encrypts routing updates.

Answer

It removes the need for subnetting.

Question 4

Match each routing concept to its most accurate meaning.

Accepted Answer

Administrative Distance is a measure of the trustworthiness of a routing information source, such as a routing protocol or a static route.. Administrative Distance measures route source trustworthiness; Metric determines best path within a protocol; Convergence is the time to reach consistent routing; Route Summarization reduces routing table size; Floating Static Route acts as a backup; ECMP enables load balancing.

Answer

Administrative Distance is the metric used by a routing protocol to determine the best path within that protocol.

Answer

Administrative Distance is the time it takes for a routing protocol to converge after a network change.

Answer

Administrative Distance is the number of hops a packet takes to reach its destination.

Question 5

A route to 10.10.10.0/24 is learned through two OSPF paths. Both have the same prefix length and the same administrative distance, but one path has a lower OSPF metric. Which path is preferred?

Accepted Answer

The path with the lower OSPF metric. The path with the lower OSPF metric is preferred. In practical terms, when the prefix and route source are the same, the router uses the routing protocol’s internal path-selection logic. For OSPF, the lower metric is the more attractive path.

This is a clean example of metric-based selection within one routing protocol. Administrative distance is not the deciding factor here because the source protocol is the same on both paths.

Answer

The path with the higher OSPF metric

Answer

Both paths equally, because the administrative distance is the same

Answer

Neither path, because two OSPF routes to the same prefix are invalid

Question 6

A router learns the same destination prefix from OSPF and EIGRP. The prefix length is identical, and both routes are valid. Which route is preferred by default?

Accepted Answer

The EIGRP route. The EIGRP route is preferred by default because EIGRP has a lower default administrative distance than OSPF. In practical terms, once the prefix length is the same, the router compares source trust. Lower administrative distance wins. EIGRP’s default of 90 beats OSPF’s default of 110.

This is not a longest-prefix question. The prefix is identical, so the decision is about source preference rather than specificity.

Answer

The OSPF route

Answer

Both routes are installed equally because the prefix length matches

Answer

Neither route is used because protocols cannot advertise the same prefix

Question 7

A router has an OSPF-learned route to a destination prefix and also a directly connected route to a broader supernet that includes that destination. The OSPF route is more specific. Which route is used for the destination?

Accepted Answer

The more specific OSPF route. The more specific OSPF route is used. In practical terms, route specificity is checked before broader route-source considerations when the prefixes are different. Even though the connected route is a directly attached source and often strongly trusted, it still loses if it is less specific than another matching route.

This is a subtle route-selection question because it combines source type and specificity. The key is that longest-prefix match comes first.

Answer

The directly connected broader route

Answer

Both routes equally

Answer

Neither route can be used because the sources differ

Question 8

What is the main purpose of this configuration?

ipv6 route 2001:db8:100::/64 GigabitEthernet0/0

Accepted Answer

It creates a specific IPv6 static route to 2001:db8:100::/64 out GigabitEthernet0/0.. This configuration creates an IPv6 static route to a specific destination prefix through the named outgoing interface. In practical terms, the router is being told exactly how to reach that remote IPv6 network. This is not a default route and not a dynamic-routing statement. It is a manually defined path to one destination prefix.

The key concept is recognizing the difference between a specific static route and a default route.

Answer

It enables OSPFv3 on GigabitEthernet0/0.

Answer

It creates an IPv6 default route.

Answer

It converts the interface into a tunnel.

Question 9

R1 is an IPv6-only branch router. The administrator wants all unknown IPv6 destinations to be sent to the upstream router at 2001:db8:ff::1. Which command best achieves that goal?

Accepted Answer

ipv6 route ::/0 2001:db8:ff::1. The correct configuration is an IPv6 default static route pointing to the upstream next hop. In practical terms, this is the IPv6 version of a route of last resort. The router does not need specific entries for every remote IPv6 network if all unknown traffic should go to the upstream device.

The key distinction is that IPv6 static routing uses IPv6 syntax and the double-colon default prefix representation. This is a foundational branch-routing concept for IPv6 deployments.

Answer

ip route 0.0.0.0 0.0.0.0 2001:db8:ff::1

Answer

ipv6 route 2001:db8:ff::/64 ::1

Answer

ipv6 default-gateway 2001:db8:ff::1

Question 10

Which WAN technology is most closely associated with establishing a direct point-to-point data-link connection between two routers over a serial link?

Accepted Answer

PPP. PPP is the WAN technology most closely associated with point-to-point serial connections between routers. In practical terms, it is a Layer 2 WAN encapsulation method commonly discussed in traditional serial WAN contexts. It supports features such as authentication and link negotiation that make it more flexible than older basic encapsulations.

This is one of the classic CCNA WAN topics.

Answer

CAPWAP

Answer

SNMP

Answer

STP

Question 11

What is the operational purpose of configuring the IPv6 route ::/0?

Accepted Answer

It provides a fallback path for unknown remote IPv6 destinations.. The configured route is a default route. In practical terms, it gives the router one simple next hop for any remote IPv6 destination that is not matched by a more specific entry. That is exactly what a small branch router often needs when it has a single upstream path.

This is the same design logic as an IPv4 default route, but with IPv6 syntax and addressing.

Answer

It enables OSPFv3 on the upstream interface.

Answer

It converts link-local addresses into global unicast addresses.

Answer

It summarizes all IPv6 routes into one /64 route.

Question 12

A company wants to connect two sites across an IP network by creating a logical tunnel between the edge routers. Which technology is most directly associated with that requirement?

Accepted Answer

GRE. GRE is the most directly associated technology because it creates a logical tunnel between routers across an existing IP network. In practical terms, it allows the routers to treat the path as a virtual point-to-point connection for encapsulated traffic.

The question is specifically about tunneling between sites, not about plain routing, management, or switching behavior.

Answer

PortFast

Answer

DHCP relay

Answer

Root guard

Question 13

An administrator configures a GRE tunnel interface on a router with the following: interface Tunnel0, tunnel source GigabitEthernet0/0, tunnel destination 192.168.2.2. What is the main purpose of this configured tunnel?

Accepted Answer

It creates a logical tunnel across another network.. GRE is a tunneling mechanism used to carry one type of traffic over another network path by encapsulating packets. In practical terms, the configuration creates a logical tunnel between endpoints so traffic can cross an underlying IP network as if a virtual path existed between them. The key point is that GRE is about tunneling, not encryption by itself.

This distinction matters because people often assume tunnels automatically imply encryption. GRE by itself does not provide that.

Answer

It enables PPP authentication on a serial interface.

Answer

It configures WPA3 security for a wireless bridge.

Answer

It enables BGP between autonomous systems automatically.

Question 14

What is an autonomous system in basic BGP terminology?

Accepted Answer

A collection of networks and routers under common administrative routing control. An autonomous system is a collection of IP networks and routers under a common routing policy or administrative control. In practical terms, it is the domain boundary concept used in BGP discussions. BGP uses AS concepts to reason about routing between separate administrative networks.

This is one of the first BGP ideas learners need to understand.

Answer

A single switch VLAN

Answer

A specific OSPF area inside one router

Answer

A type of wireless access point

Question 15

Why is a default route useful on a small branch router connected to a single upstream provider?

Accepted Answer

It provides a simple next hop for unknown destinations toward the upstream connection.. A default route is useful because it gives the branch a simple fallback next hop for destinations the router does not know specifically. In practical terms, the branch router does not need a full table of every external destination if all unknown traffic should go upstream. That keeps the design simple and efficient.

This is one of the most practical default-route use cases in small or edge networks.

Answer

It makes every route more specific.

Answer

It replaces the need for any interface addressing.

Answer

It forces all users into one VLAN.