CCNA IP Routing Practice Test 11 — 15 Questions

Question 1

Based on the exhibit, what is the most likely reason the PPP link is failing to authenticate?

Accepted Answer

The PPP authentication credentials do not match between the two sides.. The most likely reason is a credentials mismatch between the two sides of the PPP authentication setup. In practical terms, PPP authentication requires the peers to agree on the relevant identity and secret information. If those values do not align, the link may come up physically but authentication fails and the logical connection does not establish properly.

This is a very exam-relevant WAN troubleshooting scenario because it focuses on a realistic failure after the transport is already present.

Answer

The interfaces must use HDLC instead of PPP before authentication can work.

Answer

CHAP requires the routers to be in different IPv4 subnets.

Answer

PPP authentication works only over GRE tunnels.

Question 2

Based on the exhibit, which command is the best next step to verify whether the floating static route becomes active after the primary route is lost?

Accepted Answer

show ip route. The best next step is to examine the routing table directly after removing or losing the primary route. In practical terms, the purpose of a floating static route is to appear when the better route disappears. The clearest way to verify that behavior is to inspect the route table for the default route after the failure condition.

This is a simulation-style verification question. It is not asking how to configure the route, but how to confirm failover actually happened.

Answer

show vlan brief

Answer

show spanning-tree

Answer

show power inline

Question 3

Why is R1 not installing the floating static default route into the routing table?

Accepted Answer

Because the OSPF default route has a lower administrative distance than the floating static route.. The floating static default route is not installed because the primary default route is already present and has a lower administrative distance. In practical terms, a floating static route is meant to sit in reserve and appear only when the preferred route is unavailable. Since the OSPF default route is active and has a better administrative distance, the backup route is not used yet.

This is a classic route-preference question. The key idea is not just that a static route exists, but that a higher-distance static route is intentionally designed to lose until the primary path disappears.

Answer

Because static default routes can never be used when OSPF is enabled.

Answer

Because the static default route must use a /24 mask instead of 0.0.0.0.

Answer

Because the next hop of a floating route must be a loopback address.

Question 4

Match each route-selection concept to the description that best fits it.

Accepted Answer

Longest prefix match: Router selects route with the most specific subnet mask. Longest-prefix match selects the most specific matching route. Administrative distance compares trust between route sources. Metric compares candidate paths within a protocol or route source. Default route serves as a fallback when no more specific route exists.

Question 5

Why is traffic to 10.10.10.200 using the EIGRP route instead of the OSPF route, given that both routes have the same prefix length?

Accepted Answer

Because EIGRP has a lower administrative distance than OSPF for the same prefix length.. When two routes have the same prefix length, the router uses administrative distance to choose the route with the lowest value. EIGRP has a default administrative distance of 90, while OSPF uses 110. Therefore, the EIGRP route is preferred.

Answer

Because OSPF routes are never installed when EIGRP is present.

Answer

Because OSPF can be used only for IPv6 routes.

Answer

Because EIGRP routes always have a smaller subnet mask than OSPF routes.

Question 6

A router has a static route configured: ip route 10.200.0.0 255.255.0.0 GigabitEthernet0/1. The output of show ip interface brief shows that interface GigabitEthernet0/1 is administratively down. Why is the route to 10.200.0.0/16 present in the running configuration but absent from the routing table?

Accepted Answer

Because the route points to an interface that is administratively down.. The static route is absent because the outgoing interface is down. In practical terms, when a static route depends on an interface that is not operational, the router cannot use that path, so the route is not installed as usable forwarding state. The configuration line alone is not enough; the forwarding path also has to be viable.

This is a realistic static-route troubleshooting pattern because it distinguishes between configured intent and operational state.

Answer

Because static routes cannot reference exit interfaces.

Answer

Because the destination must be a /24, not a /16.

Answer

Because static routes require NTP before installation.

Question 7

R1 and R2 are connected via a GigabitEthernet link in the same IPv4 subnet, and both routers have OSPF configured in the same area. However, R1 is not learning any OSPF routes from R2. What is the most likely cause?

Accepted Answer

GigabitEthernet0/0 is configured as a passive OSPF interface on R1.. The most likely reason is that one side has the interface configured as passive, which prevents OSPF hello packets from being sent on that interface. In practical terms, the network statement alone does not guarantee neighbor formation. OSPF still needs active neighbor discovery on the link. If the interface is passive, the router advertises the connected network into OSPF but does not attempt to form an adjacency there.

This is a realistic routing troubleshooting pattern because the configuration can look mostly correct until you inspect the passive-interface setting.

Answer

The routers must use different OSPF process IDs to exchange routes.

Answer

The routers are in different IPv4 subnets.

Answer

OSPF can advertise routes only across serial links.

Question 8

Based on the exhibit, why is the static route not being used for 172.18.9.10?

Accepted Answer

Because the connected /24 route is more specific than the static /16 route.. The static route is not being used because the connected route is the more specific match. In practical terms, route selection starts with prefix specificity. The static route covers a broad /16, but the destination 172.18.9.10 also falls inside a connected /24. The /24 wins because it is more specific.

This is a classic routing interpretation question because it tests whether you apply longest-prefix logic before thinking about route source preference.

Answer

Because static routes are never used when a connected network exists anywhere in the table.

Answer

Because connected routes always have administrative distance 255.

Answer

Because static routes work only for default routing.

Question 9

A router has the following routes in its routing table: a static route to 10.60.4.16/28, an OSPF route to 10.60.4.0/24, and an EIGRP route to 10.60.0.0/16. Which route will be used for a packet destined to 10.60.4.17?

Accepted Answer

The static route to 10.60.4.16/28. The route used will be the route with the longest matching prefix. In practical terms, 10.60.4.17 falls inside the /28 route shown, and that is more specific than the broader /24 and /16 alternatives. Because specificity comes first, the /28 route wins.

This is a clean route-table interpretation problem that mirrors actual exam-style thinking very closely.

Answer

The OSPF route to 10.60.4.0/24

Answer

The EIGRP route to 10.60.0.0/16

Answer

No route at all

Question 10

A router has a static route to 10.30.5.128/25, an OSPF route to 10.30.5.0/24, and a default route 0.0.0.0/0 in its routing table. Which route will the router use for destination 10.30.5.130?

Accepted Answer

The static route to 10.30.5.128/25. The router selects the route with the longest prefix match between the destination IP and the prefixes in the routing table. 10.30.5.130 matches both 10.30.5.0/24 (prefix length 24) and 10.30.5.128/25 (prefix length 25); the /25 is more specific and wins. Option D is wrong because 10.30.5.130 falls within the subnet range of 10.30.5.128/25 (hosts .129–.254), so a valid route does exist.

Answer

The OSPF route to 10.30.5.0/24

Answer

The default route

Answer

No route, because the destination is outside all prefixes shown.

Question 11

Based on the exhibit, which route will be used for destination 192.168.10.130?

Accepted Answer

The static route to 192.168.10.128/25. The route used will be the one with the longest matching prefix. In practical terms, 192.168.10.130 matches both the /24 and the /25 prefixes shown, but the /25 is more specific. Because longest-prefix match comes first, the router uses the /25 route even though other matching routes are present.

This is a clean route-table interpretation question that is very close to real exam reasoning.

Answer

The OSPF route to 192.168.10.0/24

Answer

The default route

Answer

No route at all

Question 12

Why does traffic to 172.31.80.10 use the RIP route (172.31.80.0/24) instead of the static route (172.31.0.0/16)?

Accepted Answer

Because the RIP /24 route is more specific than the static /16 route.. Traffic uses the RIP route because the static route is less specific than the RIP route. In practical terms, longest-prefix match is always evaluated first. Even though the static route is manually configured, the more specific RIP prefix wins because it describes the destination more precisely.

This is a strong route-selection item because it tests whether you can prioritize specificity ahead of route source preference.

Answer

Because RIP always overrides static routing.

Answer

Because static routes cannot be used for private IPv4 space.

Answer

Because the static route is automatically removed whenever RIP is enabled.

Question 13

A router has a static route and a RIP route for the same destination prefix. What is the primary reason the static route is preferred over the RIP route?

Accepted Answer

Because the static route has a lower administrative distance for the same prefix.. The static route is preferred because both routes describe the same destination prefix and the static route has the lower administrative distance. In practical terms, longest-prefix match does not break the tie because the prefixes are equal. The router then compares source trust, and static routing wins over RIP by default.

This is a core route-selection concept and a very exam-relevant comparison.

Answer

Because RIP can never be installed when static routing is configured anywhere.

Answer

Because RIP is valid only for host routes.

Answer

Because static routes are always more specific than RIP routes.

Question 14

R1 and R2 are connected via a shared Ethernet segment. Both routers are configured in OSPF area 0 and are on the same IP subnet. OSPF authentication is enabled on both interfaces, but the adjacency is not forming. What is the most likely reason?

Accepted Answer

The OSPF authentication key does not match on the two routers.. The most likely reason is an OSPF authentication mismatch. In practical terms, both routers are on the same IP subnet and in the same area, but they are not using the same authentication key on the shared link. OSPF neighbors must agree on key authentication parameters before they will trust each other enough to form an adjacency.

This is a classic CCNA troubleshooting pattern because the configuration looks almost correct until you compare the security settings carefully.

Answer

The routers must use different OSPF areas to become neighbors.

Answer

OSPF message-digest authentication can be used only on serial links.

Answer

The routers must remove IP addressing before OSPF can form.

Question 15

When two routes to the same destination are learned by OSPF from different paths, what criterion does OSPF use to select the best path?

Accepted Answer

Lowest OSPF cost. Within OSPF, the router compares the total path cost to the destination. Lower cost is preferred. Administrative distance is used when comparing routes from different routing sources, not between two OSPF paths.

Answer

Lowest administrative distance

Answer

Highest bandwidth of the first hop only

Answer

Lowest next-hop IP address

CCNA IP Routing Practice Test 11 — 15 Questions

Exhibit

CCNA IP Routing Practice Test 11 — 15 Questions

Exhibit