CCNA IP Routing Practice Test 7 — 15 Questions

Question 1

You are connected to R1 via console. R1 and R2 are configured with EIGRP AS 100. R1's loopback0 (1.1.1.1/32) should be advertised into EIGRP. However, after configuration, R2 does not have a route to 1.1.1.1/32. You need to verify the EIGRP configuration on R1 and R2 to determine why the route is missing. Use show commands to identify the issue.

Accepted Answer

Use 'show ip eigrp interfaces' on R1 to verify that EIGRP is enabled on the interface facing R2 and that it is not passive.. The most likely reason R2 lacks the 1.1.1.1/32 route is that R1 is not forming an EIGRP adjacency on the interface facing R2 — either EIGRP is not enabled on that interface or the interface is configured as passive. 'show ip eigrp interfaces' on R1 directly reveals which interfaces are participating in EIGRP and whether they are passive, making it the correct first diagnostic step.

Answer

Use 'show ip eigrp topology' on R1 to confirm that the 1.1.1.1/32 route is in the EIGRP topology table.

Answer

Use 'show ip route eigrp' on R1 to verify that the 1.1.1.1/32 route is in the routing table.

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Use 'show ip protocols' on R2 to verify that EIGRP AS 100 is configured and that the network statement includes the subnet of the interface facing R1.

Question 2

You are connected to R1 via console. R1 is a new router connecting two subnets: 192.168.1.0/24 on G0/0 and 192.168.2.0/24 on G0/1. You need to configure IPv6 static routes so that hosts on these subnets can reach the IPv6 Internet via R2 (2001:db8:1::2). R1's G0/0 has IPv6 address 2001:db8:1::1/64, and R2 is the next-hop. Also configure a default IPv6 route toward R2.

Accepted Answer

ipv6 route ::/0 2001:db8:1::2. The default IPv6 route is configured with the all-zeros prefix ::/0, which matches any IPv6 destination not covered by a more specific route. The next-hop address 2001:db8:1::2 is R2's link-local or global address on the directly connected segment, so the router can resolve it via G0/0. This single command satisfies the requirement to send all unknown IPv6 traffic toward R2, enabling hosts on both subnets to reach the IPv6 Internet.

Answer

ipv6 route 2001:db8:1::/64 2001:db8:1::2

Answer

ipv6 route ::/0 g0/0

Answer

ipv6 route 2001:db8:1::2/128 g0/0

Question 3

You are connected to R1 via console. R1 is connected to R2 via GigabitEthernet0/0 (10.0.0.1/30) and to R3 via GigabitEthernet0/1 (10.0.0.5/30). R1 has a management subnet 192.168.1.0/24 connected to GigabitEthernet0/2. The network administrator wants to ensure that traffic from the management subnet to the Internet (203.0.113.0/24) uses R2 as the primary path and R3 as a backup. Currently, OSPF is running with default metrics. You must configure a floating static route that will be used only if the OSPF route fails.

Accepted Answer

ip route 203.0.113.0 255.255.255.0 10.0.0.6 150. The floating static route is configured with an administrative distance of 150, which is higher than OSPF's default AD of 110. This ensures that the static route is only installed in the routing table when the OSPF route is not present (e.g., due to a failure). The next-hop is R3's IP on the directly connected link.

Answer

ip route 203.0.113.0 255.255.255.0 10.0.0.2 150

Answer

ip route 203.0.113.0 255.255.255.0 10.0.0.6 110

Answer

ip route 0.0.0.0 0.0.0.0 10.0.0.6 150

Question 4

You are connected to R1 via console. R1 and R2 are connected via two serial links: Serial0/0/0 (10.0.0.1/30) and Serial0/0/1 (10.0.0.5/30). OSPF is configured on both links. However, the OSPF neighbor adjacency is stuck in EXSTART/EXCHANGE state. You suspect a mismatch in OSPF parameters. You need to identify and fix the issue.

Accepted Answer

Check and adjust the MTU on the serial interfaces to match.. OSPF neighbors stuck in EXSTART/EXCHANGE almost always indicate an MTU mismatch on the link. During the Database Description (DBD) exchange, routers negotiate the master/slave relationship and exchange DBD packets; if the MTU values differ, the DBD packets are dropped and the adjacency never progresses past EXCHANGE. Checking and matching the MTU on both serial interfaces resolves the issue.

Answer

Check and adjust the OSPF hello and dead timers to match.

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Check and adjust the OSPF network type on the interfaces to match.

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Check and adjust the OSPF area ID on the interfaces to match.

Question 5

You are connected to R1 via console. R1 is connected to R2 via GigabitEthernet0/0 and to R3 via GigabitEthernet0/1. OSPF has been configured, but R1 is not forming a full adjacency with R2. You run `show ip ospf neighbor` on R1 and see R2 stuck in EXSTART state. You also run `show ip ospf interface GigabitEthernet0/0` and see the network type is broadcast. You need to identify and resolve the issue.

Accepted Answer

Change the OSPF network type on R1's GigabitEthernet0/0 interface to point-to-point.. R1's Gi0/0 defaults to OSPF broadcast network type, while R2 is likely configured as point-to-point. This mismatch prevents the routers from forming a full adjacency, often leaving them stuck in EXSTART or 2-WAY state. Changing R1's interface to point-to-point aligns the network types, allowing adjacency to form. The other options are incorrect because hello interval mismatches (B) or DR priority (C) are not the root cause, and adding the broadcast command (D) would not fix a point-to-point mismatch.

Answer

Increase the OSPF hello interval on R1's GigabitEthernet0/0 interface to match R2's hello interval.

Answer

Configure the OSPF priority on R1's GigabitEthernet0/0 interface to 0 to prevent it from becoming the DR.

Answer

Add the 'ip ospf network broadcast' command on R1's GigabitEthernet0/0 interface.

Question 6

You are connected to R1 via console. R1 has two paths to the Internet: primary via ISP1 (G0/0) and backup via ISP2 (G0/1). The primary route has an administrative distance of 1, and the backup should only be used if the primary fails. Currently, both routes are active. You need to configure a floating static route for the backup.

Accepted Answer

ip route 0.0.0.0 0.0.0.0 G0/1 200. A floating static route is configured with an administrative distance higher than the primary route so it only enters the routing table when the primary fails. Since the primary route has an AD of 1, the backup must use a higher AD — 200 is a valid choice that exceeds 1 and ensures the backup is inactive while the primary is up. The command 'ip route 0.0.0.0 0.0.0.0 G0/1 200' correctly sets the next-hop interface and the floating AD.

Answer

ip route 0.0.0.0 0.0.0.0 G0/1 1

Answer

ip route 0.0.0.0 0.0.0.0 G0/1 0

Answer

ip route 0.0.0.0 0.0.0.0 G0/1 255

Question 7

You are connected to R1 via the console. R1 and R2 are configured with EIGRP AS 100. R1 has two paths to the 172.16.1.0/24 network: one via a FastEthernet link to R2 (bandwidth 100 Mbps, delay 100 microseconds) and another via a serial link to R2 (bandwidth 1.544 Mbps, delay 20000 microseconds). The EIGRP metric is calculated using the default K-values. The FastEthernet link is preferred, but you need to make the serial link the backup by adjusting the administrative distance.

Accepted Answer

Configure a static route to 172.16.1.0/24 with next-hop 10.0.0.6 and administrative distance 170.. A floating static route is configured with an administrative distance of 170, which is higher than EIGRP's default distance of 90. This ensures that the static route is only used when the EIGRP route is not available. The static route points to the next-hop IP address of R2's serial interface.

Answer

Configure a static route to 172.16.1.0/24 with next-hop 10.0.0.6 and administrative distance 90.

Answer

Configure a static route to 172.16.1.0/24 with next-hop 10.0.0.6 and administrative distance 1.

Answer

Configure a static route to 172.16.1.0/24 with next-hop 10.0.0.6 and administrative distance 255.

Question 8

Which three statements about the routing table and route selection are correct? (Choose three.)

Accepted Answer

If two routes have the same prefix length and metric, load balancing can occur across both.. The route with the longest prefix match is always preferred because it is the most specific. A directly connected route has an administrative distance (AD) of 0 by default. A static route has a default AD of 1. The load-balancing statement is false because it omits the requirement that the routes must also have the same AD; if AD differs, load balancing does not occur.

Answer

A default route (0.0.0.0/0) is always preferred over any more specific route.

Answer

An OSPF inter-area route has a lower administrative distance than an OSPF intra-area route.

Answer

The administrative distance of a static route is always 1.

Question 9

Which three of the following are true regarding the forwarding decision process in a router? (Choose three.)

Accepted Answer

The router performs a recursive route lookup if the next-hop address in a static route is not directly connected.. The three true statements are: (A) The router performs a recursive route lookup when the next-hop address in a static route is not directly connected, meaning the router must find a route to that next-hop address before forwarding. (B) The Forwarding Information Base (FIB) is used in Cisco Express Forwarding (CEF) mode to provide fast, hardware-based packet switching by pre-populating the forwarding table from the routing table. (C) When a packet arrives, the router first checks the routing table (RIB) for the best matching route, which is the longest prefix match, to determine the next-hop and outgoing interface. The other statements are false: The router does not always perform an ARP request for every destination IP; ARP is only for next-hop addresses on the same subnet. The router does not skip the routing table for directly connected subnets; it still checks the routing table. The router rewrites the source MAC address to the MAC address of the outgoing interface, not necessarily the next-hop router's MAC, and this occurs per-hop.

Answer

The router always performs an ARP request for every destination IP address in a packet.

Answer

If the destination IP is on the same subnet as an interface, the router forwards the packet directly without checking the routing table.

Answer

The router rewrites the source MAC address to the MAC address of the next-hop router for every forwarded packet.

Question 10

Which four of the following statements about IPv4 static routing are true? (Choose all that apply. There are four correct answers.)

Accepted Answer

A default static route uses 0.0.0.0/0 as the destination network.. A default static route with destination 0.0.0.0/0 matches all packets when no more specific route exists, acting as a gateway of last resort. A floating static route uses a higher administrative distance (e.g., 150) than the dynamic protocol's default (e.g., 110 for OSPF), so it only appears in the routing table if the dynamic route fails. A fully specified static route includes both the exit interface and next-hop IP, eliminating recursive lookups. A recursive static route specifies only the next-hop IP, forcing the router to perform multiple routing table lookups to find the exit interface. Option D is incorrect because a static route specifying only the next-hop IP requires a recursive lookup to find the exit interface, not ARP directly. Option E is incorrect because an IPv4 static route cannot use an IPv6 address as next hop; the next-hop address must be in the same address family.

Answer

A static route pointing to a next-hop IP address only is resolved through ARP on the router.

Answer

An IPv4 static route can use an IPv6 address as the next hop.

Question 11

Which four of the following statements about distance vector routing protocols (e.g., RIP, EIGRP) are correct? (Choose all that apply. There are three correct answers.)

Accepted Answer

EIGRP maintains separate feasible distance and advertised distance values for each route.. RIPv2 sends updates to multicast address 224.0.0.9, ensuring only RIPv2 routers process them. EIGRP maintains both feasible distance (best metric to a destination) and advertised distance (metric reported by the next-hop router) to support its loop-free DUAL algorithm. Split horizon prevents routing loops by not advertising a route back out the interface from which it was learned. The statement about reliance on Bellman-Ford is false because EIGRP uses DUAL, not Bellman-Ford; the statement that distance vector protocols require a full topological map is false (that describes link-state protocols); and EIGRP does not support unequal-cost load balancing by default—it requires the 'variance' command.

Answer

EIGRP supports both equal-cost and unequal-cost load balancing by default.

Answer

They require a full topological map of the network to calculate the best path.

Question 12

Which three of the following are characteristics of a distance-vector routing protocol? (Choose three.)

Accepted Answer

Routers send their entire routing table to directly connected neighbors at regular intervals.. Distance-vector routing protocols are characterized by periodic full routing table updates to directly connected neighbors, as seen in classic protocols like RIP. However, advanced distance-vector protocols such as EIGRP do not send their full routing table at regular intervals; they perform a one-time full exchange during neighbor formation and then send only partial, triggered updates. Regardless of this distinction, all distance-vector protocols have a limited view of the network topology (often called 'routing by rumor'), rely on hop count or composite metrics, and converge more slowly than link-state protocols in large networks. The correct options highlight these general characteristics of distance-vector protocols.

Answer

Routers flood link-state advertisements (LSAs) to all routers in the area.

Answer

Routers maintain a complete map of the entire network topology.

Answer

Routers use the Shortest Path First (SPF) algorithm to calculate routes.

Question 13

Drag and drop the following steps into the correct order to configure and verify a floating IPv4 static route as a backup path.

Accepted Answer

Configure the primary static route to the destination network using the primary next-hop address, leaving the administrative distance at its default value (1).. The correct order begins with configuring the primary static route (A) because it defines the main path. Checking its administrative distance (B) (default 1) is essential to then set a higher AD for the floating route (C), ensuring it acts only as a backup. Next, verify the routing table to see only the primary route installed (D). Simulate a failure by shutting down the primary interface (E) to trigger failover. Finally, recheck the routing table to confirm the floating route is now active (F).

Question 14

Drag and drop the following steps into the correct order to configure a primary default static route and a floating default static route on a Cisco router.

Accepted Answer

Enter global configuration mode using the configure terminal command.. The correct order is A, B, C, D, E. First, enter global configuration mode using 'configure terminal' (A). Then configure the primary default static route with next-hop 203.0.113.1 (B). Next, configure the floating default static route with a higher administrative distance of 5 (C). After that, exit configuration mode with the 'end' command (D). Finally, verify the static routes using 'show ip route static' (E).

Question 15

A network engineer notices that an OSPF adjacency between R1 and R2 is flapping between FULL and DOWN state every 40 seconds. The dead interval on both routers is configured as 40 seconds. The hello interval on R1 is 10 seconds, and on R2 it is 30 seconds. What is the most likely cause?

Accepted Answer

Mismatched hello intervals cause the dead timer on R1 to expire before receiving a hello from R2, tearing down the adjacency.. In OSPF, hello and dead intervals must match exactly between neighbors. A mismatch causes hello packets to be rejected, so the adjacency stays DOWN rather than flapping FULL/DOWN. Furthermore, the timers given would not cause R1 to expire: R2 sends hellos every 30s, which is less than R1's 40s dead interval. Therefore none of the options correctly explains the flapping; the question scenario is invalid.

Answer

Duplicate OSPF router IDs are causing the adjacency to reset each time the mismatched routers see each other's LSAs.

Answer

A network type mismatch between broadcast and point-to-point is causing periodic DR/BDR elections that reset the adjacency.

Answer

An OSPF authentication mismatch is causing periodic rejection of hello packets on one router.