CCNA IP Routing Questions

Option B is incorrect because the OSPF route to 10.1.1.0/24 is less specific than the /26 static route. Even though OSPF is a dynamic protocol, the router prefers the more specific static route.

Option C is incorrect since the OSPF route to 10.1.0.0/16 covers a much larger network and is less specific than both the /24 and /26 routes, so it is not chosen for 10.1.1.70.

Option D is incorrect because the default route is only used when no other more specific route matches the destination. Here, the /26 static route is more specific, so the default route is ignored.

OSPFv2 supports only IPv4; OSPFv3 is required for IPv6 routing.

OSPFv3 uses a 32-bit router-id, which must be manually configured or derived from an IPv4 address; without it, the process cannot operate.

Verification commands like 'show ospfv3 neighbor' and 'show ipv6 route ospf' are necessary to ensure OSPFv3 is functioning correctly.

This statement is false because passive-interface does not prevent the network from being advertised; the prefix is still injected into the OSPF LSAs.

Passive-interface only stops OSPF control packets; data traffic forwarding continues normally on the interface.

The passive-interface command does not remove the network from the OSPF routing table; the network is still reachable via other interfaces.

Incorrect. Default routes are less preferred than connected or static routes because routers always choose the most specific route first based on longest prefix match.

Incorrect. Default routes can exist alongside dynamic routing protocols and do not require dynamic routing to be disabled; they complement dynamic routes as a last resort.

Incorrect. A default route does not remove the need for route selection logic; routers still evaluate all routes and prefer more specific matches before using the default.

Option B is incorrect because metrics like OSPF cost are only compared among routes from the same protocol; the router does not compare OSPF cost against static route administrative distance.

Option D is incorrect because routes from different sources with different administrative distances do not qualify for equal-cost multipath (ECMP), so both routes are not installed simultaneously.

Skips the more likely and fundamental subnet mask check, which would render timer issues irrelevant until resolved.

Ignores the more foundational IP addressing check that could also cause the issue, and area troubleshooting would be misleading if the subnet mask is incorrect.

Jumps to an OSPF-specific command without first verifying the fundamental IP subnet configuration, which is a more direct cause of failed adjacencies on broadcast links.

The OSPF /24 route is less specific than the static /25 route. Since longest-prefix match prefers the more specific route, the OSPF route is not used for 192.168.1.200.

Both routes do not automatically load-balance because they have different prefix lengths. Load balancing requires equal prefix length and equal cost routes, which is not the case here.

Neither route is incorrect because overlapping routes are common and resolved by longest-prefix match. The router uses the more specific static /25 route, so traffic is forwarded correctly.

The passive-interface default command would block Hellos, preventing the adjacency from ever reaching the EXSTART/EXCHANGE state.

An OSPF area mismatch would cause Hellos to be ignored, so the adjacency would not progress past the Down or Init state.

Conflicting router IDs would prevent the routers from becoming neighbors at all, as OSPF requires unique router IDs within an area.

Static routes do not always win; they have a default administrative distance of 1, but in this scenario the static route was configured with AD 150, which is higher than OSPF's AD 110. Therefore, the OSPF route is preferred.

A router installs only the best route (lowest AD) for a given prefix into the routing table. Different AD values do not cause both routes to be installed; the route with the lower AD is chosen.

A floating static route is a static route with a higher AD than the dynamic route, so it remains inactive as a backup. In this case, the static route is floating, but it is still valid and will be used if the OSPF route is lost. The question asks which route is installed, and the OSPF route is installed, not neither.

Router ID duplication does not explain a completely empty neighbor table; neighbors would still be detected via hellos.

Network type mismatch would likely still result in hellos being received and a neighbor entry appearing, just not advancing to full adjacency. The complete absence of neighbors points to a transport issue.

Candidates often remember MTU mismatch as a frequent OSPF problem, but it manifests after neighbor discovery, not as a complete lack of neighbors.

This option is incorrect because the OSPF route to 192.168.10.0/24 has a shorter prefix length (/24) than the static /25 route, so it is less specific and will not be chosen for the destination IP.

This option is incorrect because the default route is only used when no other specific routes match the destination. Since both the /24 and /25 routes match, the default route is ignored.

This option is incorrect because the destination IP clearly matches multiple routes in the routing table, so the router will select the best match rather than having no route at all.

Incorrect because OSPF fully supports GigabitEthernet interfaces. There is no restriction on running OSPF on these interfaces in Cisco IOS.

Incorrect because both routers being in area 0 is necessary for adjacency on that segment. Matching area IDs help form adjacency rather than prevent it.

Incorrect because router IDs must be unique, not identical. Matching router IDs do not cause adjacency to form; in fact, duplicate router IDs cause routing problems but not adjacency failure due to subnet mismatch.

Option B is incorrect because static routes do not always override OSPF routes regardless of specificity. Prefix length is evaluated before administrative distance, so a less specific static route would not override a more specific OSPF route.

Option C is incorrect because OSPF can route any IP address range, including Class B networks like 172.16.0.0/16. There is no limitation on OSPF routing based on IP class.

Option D is incorrect because the routing decision here is based on prefix length, not on comparing OSPF metric and static route administrative distance. The static route’s longer prefix length takes precedence.

This option is incorrect because OSPF’s administrative distance of 110 is higher than EIGRP’s 90, so OSPF routes are less preferred when both advertise the same prefix length.

This option is incorrect because routers do not treat routes from different protocols with equal administrative distance; they prefer the route with the lower administrative distance, so both routes are not equally preferred.

This option is incorrect because routers can and often do receive overlapping routes from multiple routing protocols and must compare administrative distance to choose the best route.

This option is incorrect because route preference is determined by administrative distance, not by a blanket rule that dynamic routes always beat static routes.

This option is incorrect because identical prefix length alone does not guarantee equal route preference; administrative distance is the deciding factor.

This option is incorrect because routers do not drop duplicate routing information; instead, they choose the best route based on administrative distance.

The specific factual error is that an AD of 1 does not create a floating static route; it matches the primary route's AD, so both routes are used.

The specific factual error is that AD 0 is used for directly connected routes; using it for a static route would override the primary route.

The specific factual error is that AD 255 means the route is not trusted and will not be installed; it cannot serve as a backup.

The question states the serial link is up/up on both sides, meaning the interface is not administratively down. An administratively down interface would show as 'administratively down' in the interface status, not 'up/up'.

Both interfaces have IPv6 addresses in the 2001:DB8:1:1::/64 subnet, so the subnet matches. OSPFv3 does not require interfaces to be in the same subnet for adjacency, but it does require link-local addresses to be reachable. However, the given addresses are global unicast, and the subnet match is not the issue here.

The router-id is configured on R2 as 2.2.2.2, as stated in the existing explanation. OSPFv3 requires a router-id, and it is present, so this is not the cause.

EIGRP, a distance vector protocol listed as an example, uses DUAL, not Bellman-Ford, making the statement inaccurate.

Requiring a full topological map is characteristic of link-state protocols, not distance vector protocols.

EIGRP does not support unequal-cost load balancing by default; it must be explicitly enabled with the 'variance' command.

Using a static route with administrative distance 1 makes it the most preferred route immediately, overriding the OSPF-learned route. This does not meet the requirement of using the static route only when the OSPF route disappears.

Setting a static route with metric 0 does not influence route preference between static and OSPF routes because metrics affect path selection within routing protocols, not across different route sources.

Redistributing the static route into OSPF advertises it dynamically but does not create a backup route that activates only when the OSPF route disappears. Redistribution is unnecessary for this backup behavior.

This option is incorrect because the command shown is a static route configuration, not a command to enable OSPFv3 on an interface. OSPFv3 requires separate routing protocol configuration commands.

This option is incorrect because the prefix specified is a specific network (2001:db8:100::/64), not the default IPv6 route (::/0). Therefore, it does not create a default route.

This option is incorrect because static route commands do not convert interfaces into tunnels. Tunnel interfaces require explicit tunnel configuration commands, which are not present here.

A missing virtual IP on one router does not cause both to be Active; the router without the virtual IP cannot claim the Active role for that address.

A group number mismatch does not cause both routers to appear as Active for the same virtual IP; they would be in separate groups.

Equal priority does not lead to multiple Active routers; HSRP uses the interface IP address as a tiebreaker to elect a single Active router.

Incorrect. While using a loopback interface as the router ID is recommended for stability, it is not required for OSPF neighbor adjacency to form.

Incorrect. A /30 subnet mask is valid for point-to-point OSPF links and does not prevent neighbor relationships from forming.

Incorrect. The Designated Router (DR) election occurs after adjacency formation and does not prevent neighbors from forming if area IDs mismatch.

HSRP tie-breaking uses the highest IP address on the HSRP interface, not the MAC address. The MAC address is used for virtual MAC assignment but does not influence election.

Preemption is disabled by default in HSRP; it must be explicitly configured with the 'standby preempt' command. Without preemption, a higher priority router will not take over active role from a lower priority router that is already active.

The standby router is the router with the second-highest priority, not the lowest. The lowest priority router would only become standby if all other routers fail, as it is the least preferred.

This option is incorrect because it uses the IPv4 static route syntax (ip route) with an IPv6 next-hop address, which is invalid and will not configure a proper IPv6 route.

This command creates a specific static route to the 2001:db8:ff::/64 prefix with a next hop of ::1, which is not a default route and does not forward all unknown IPv6 traffic.

The ipv6 default-gateway command is not used for static routing configuration and does not install a default route in the routing table, making it ineffective for forwarding unknown IPv6 destinations.

The floating route must have a higher AD than the primary route to act as a backup; setting it to 1 would make it preferred over the primary default route, violating the requirement.

AD 255 is reserved for routes that are not to be installed; a floating route needs an AD higher than the primary but less than 255 to be usable as backup.

The floating route is required by the scenario; removing it would eliminate the backup path, which is not the intended fix.

Removing the track command would prevent R1 from decrementing priority when G0/1 fails, violating the requirement to track the interface.

Configuring preempt on R2 might allow it to take over, but the task only asks to fix R1; the primary issue is the virtual IP mismatch on R1.

Setting priority to 100 (the default) without preempt? Actually, R1 already has preempt, but with equal priority, the highest IP wins, which might be R2, so R1 might not become active. Increasing priority to 110 is required.

Incorrect because RIP does not always override static routes. Static routes have a lower administrative distance and are preferred when prefix lengths are equal, so this statement is false.

Incorrect because static routes can be used with private IPv4 address space without issue. There is no restriction preventing static routing of private addresses.

Incorrect because enabling RIP does not automatically remove static routes. Static routes remain active unless manually removed or overridden by a more specific route.

Option B is incorrect because a default route is less specific than a /24 route and is only used if no more specific route exists, not because it is simpler.

Option D is incorrect because routers do not ignore subnet masks; prefix length is fundamental to longest-prefix match and route selection.

Option E is incorrect since a /24 prefix is more specific than a /16 prefix, contradicting the statement that a /16 is always more specific.

The AD must be greater than 90 to ensure the static route is only used when EIGRP fails. An AD of 90 does not create a floating static route.

A floating static route must have a higher AD than the primary route. An AD of 85 is lower than 90, so it would be preferred over EIGRP.

The default AD for static routes is 1, which is lower than EIGRP's 90. Without specifying a higher AD, the static route will be preferred and not act as a floating static route.

Static routes are not permanent; they are removed from the routing table if the next-hop interface goes down or the next-hop IP becomes unreachable, because the route is no longer valid.

A static route does not automatically change into a default route; default routes are explicitly configured (e.g., ip route 0.0.0.0 0.0.0.0 next-hop) and are not derived from other static routes.

A static route does not become an OSPF external route automatically; OSPF routes are learned through the OSPF protocol, and a static route remains static unless redistributed into OSPF via configuration.

Lowest administrative distance is incorrect because administrative distance is used to compare routes from different routing protocols, not to select between multiple OSPF-learned routes. Within OSPF, all routes have the same administrative distance, so this criterion does not apply.

Highest bandwidth of the first hop only is incorrect because OSPF considers the cumulative cost of the entire path, not just the bandwidth of the first hop. Focusing only on the first hop bandwidth ignores the cost of subsequent links.

Lowest next-hop IP address is incorrect because OSPF does not use the next-hop IP address as a criterion for route selection. The protocol relies exclusively on the cost metric to determine the best path.

Loopback0 is not enabled for OSPF, so its prefix is not advertised into OSPF.

The 'network' command is invalid in OSPFv3 for IPv6; only interface-level 'ipv6 ospf ... area' commands are used.

Applying 'passive-interface GigabitEthernet0/0' prevents OSPF from forming a neighbor adjacency on the link, breaking the verification of neighbor state.

The route being in R1's topology does not guarantee it is advertised to R2; the problem is more likely with the neighbor adjacency or outbound filters.

The loopback is a directly connected interface, so it will not appear in the EIGRP routing table; it is injected into EIGRP via the network statement. This command is irrelevant for checking the advertisement.

The problem is likely on R1, not R2. R2's configuration may be fine, but if R1 is not sending the route, R2 will never learn it. This command focuses on R2, which is not the source of the issue.

Option A incorrectly states that adjacency formation has failed. FULL state actually indicates a successful adjacency, and the /DR suffix refers to the neighbor’s role, not failure.

Option C is incorrect because exchanging only link-state requests happens in earlier OSPF states, not in FULL adjacency, which means all exchanges are complete.

Option D is invalid because the output shows native OSPF neighbor information, not BGP redistribution, so the neighbor is not learned through BGP.

The IPv6 static route should use a fully specified next-hop (IPv6 address) rather than just an exit interface to avoid recursive routing failures.

Floating static routes require a higher administrative distance (e.g., 200) so they are only used when the primary route is unavailable.

A fully specified IPv6 static route includes both the exit interface and the next-hop IPv6 address to ensure proper routing.

Candidates assume that OSPF adjacency failures on Ethernet links are often due to network type mismatches, without considering that the default settings match.

Candidates may remember that duplicate router‑IDs break OSPF and jump to this conclusion without first analyzing the simpler configuration issue.

Many students learn that timer mismatches are a common OSPF problem and may incorrectly assume they are the cause when the real issue is a basic configuration oversight.

Both routers are explicitly in OSPF area 0, so they are not in different areas.

OSPF neighbor formation does not depend on matching hostnames; router IDs and interface parameters are what matter.

Since the routers can ping each other, IP reachability exists, indicating the subnet mask is not preventing OSPF multicast packets from being delivered.

Static routes do not always override dynamic routes; route selection is based on administrative distance. OSPF has a default AD of 110, which is lower than 200, so the OSPF route is preferred. The statement that static routes always win is incorrect because AD values determine preference.

Routers install only the best route (lowest AD) for a given destination in the routing table, unless equal-cost multipath (ECMP) is configured with identical metrics. Since OSPF and static routes have different ADs, they are not installed simultaneously; only the OSPF route is used.

The router does not remove the OSPF route because the static route has a manually configured distance. The OSPF route has a lower AD (110) than the static route's AD (200), so OSPF remains the preferred route and stays in the routing table.

This misinterprets AD: after the primary route is gone, any route with a higher AD (i.e., lower numeric value) is no longer present, so the floating static route should be installed if reachable.

Permanent is rarely needed and does not make a route usable when the interface is down; it only keeps the routing table entry present, but traffic cannot be forwarded.

Changing a static route metric is not possible, and even if it were, it would not change the fact that the specified interface is down.

An OSPF area mismatch prevents routers from forming a full adjacency; they typically remain in the INIT or 2-WAY state, not EXSTART. The EXSTART state indicates that the routers have already exchanged Hello packets and are attempting to negotiate the master/slave relationship, which requires matching area IDs.

Duplicate router IDs cause OSPF to behave unpredictably, often resulting in flapping adjacencies or multiple neighbors with the same ID, but they do not typically cause a stuck EXSTART state on a single link. The routers would still progress through the states, but the adjacency may be unstable.

A missing default route on R2 does not affect OSPF adjacency formation. OSPF neighbors exchange routing information using multicast Hello and DD packets, which do not require a default route. The adjacency process is independent of the routing table content.

The priority value is higher than the default, which would make R1 active instead of standby.

The decrement value does not match the required 20; it is 30.

The tracked interface is wrong; it should be GigabitEthernet0/1, not GigabitEthernet0/0.

CAPWAP is a control and provisioning protocol for wireless access points and controllers, not a WAN encapsulation for serial links. It operates at the application layer and is used in wireless LAN architectures, not for point-to-point data-link connections.

SNMP is an application-layer protocol for network management and monitoring, used to collect statistics and configure devices. It does not provide data-link layer encapsulation or establish point-to-point connections over serial links.

STP is a Layer 2 protocol that prevents loops in Ethernet switched networks by blocking redundant paths. It has no role in WAN serial links, which are point-to-point and inherently loop-free.

The default route is incorrect because it is the least specific route and only used when no other matching routes exist; here, more specific routes are available.

The OSPF route to 10.1.1.0/24 is less specific than the /25 static route, so it is not selected despite matching the destination IP address.

The OSPF route to 10.1.0.0/16 is the least specific among the options and will not be chosen when more specific routes like /24 or /25 exist.

The specific factual error is that the default route configuration is correct as given; there is no need to modify it. Changing the AD of the default route could cause routing issues.

The specific factual error is swapping the administrative distances: the primary route should have a lower AD than the floating route. Here, the primary route has AD 150 and the floating route has AD 1, causing the backup to be preferred.

The specific factual error is that static routes without an AD default to 1, so both routes would have equal AD. The floating route must have a higher AD (e.g., 150) to act as a backup.

This places the adjacency in area 1, not area 0 as required, and does not fix the timer mismatch on R2.

This does not fix the hello/dead timer mismatch; MTU is already matching at 1500.

This leaves the hello interval mismatched (10 vs 5) and alters the dead interval unnecessarily; R2 needs hello interval set to 5, not dead interval.

The specific factual error: An administrative distance of 255 is reserved for routes that are not considered valid; they are not installed in the routing table.

The specific factual error: The permanent keyword forces the route to stay in the routing table regardless of reachability, which is the opposite of what is needed.

The specific factual error: The AD values determine route preference; swapping them changes which route is preferred but does not address the removal of the route when the next-hop is unreachable.

Metrics from different routing protocols are not comparable because each protocol uses its own metric calculation (e.g., OSPF uses cost based on bandwidth, EIGRP uses composite metric based on bandwidth and delay). The router uses administrative distance to choose between routes from different protocols, not metric values.

A router installs only the best route to a destination in the routing table, unless equal-cost load balancing is configured. Since OSPF and EIGRP have different administrative distances, only the route with the lower AD is installed. Both routes cannot be installed simultaneously for the same prefix.

The router does compare routes from different protocols using administrative distance, not metrics. Since the metrics are from different protocols, they are not directly comparable, but the router still selects one route based on AD. Therefore, one route will be installed.

This option is incorrect because a static route with an administrative distance of 250 does not override the OSPF default route, which has a lower AD of 110. The high AD prevents immediate override.

This option is incorrect because the static default route does not cause the router to ignore all default routes. Instead, it remains as a backup and only becomes active if the OSPF route disappears.

This option is incorrect because administrative distance does not change the route prefix or convert a default route into a host route. It only influences route preference and selection.

The OSPF 10.0.0.0/8 route is less specific than the static 10.10.0.0/16 route. Since the router uses longest-prefix match, the broader /8 route is not selected for traffic destined to 10.10.20.1.

The default route would only be used if no more specific matching routes exist. Since both OSPF and static routes match, and the static route is more specific, the default route is not used here.

Overlapping networks are common in routing tables and do not prevent route selection. The router resolves overlapping prefixes by choosing the longest-prefix match, so this option is incorrect.

Option B is incorrect because the static route command does not enable OSPFv3. OSPFv3 requires separate configuration commands and is a dynamic routing protocol, unlike static routes.

Option C is incorrect because routing does not convert link-local addresses into global unicast addresses. Address types remain consistent, and routing forwards packets based on existing address formats.

Option D is incorrect because ::/0 is a default route covering all IPv6 addresses, not a summary route with a /64 prefix. Summarization involves aggregating multiple routes into a larger prefix, which is not the case here.

The route 10.50.0.0/16 is the least specific among the options because it covers a large range of IP addresses. Although it matches the destination IP 10.50.10.140, it is overridden by more specific routes with longer subnet masks, so it is not chosen.

The route 10.50.10.0/24 is more specific than the /16 but less specific than the /25. Since 10.50.10.140 falls within the /25 subnet, the router prefers the /25 route over this /24 route, making this option incorrect.

The default route is only used when no other matching routes exist. Since multiple specific routes match 10.50.10.140, the router will not use the default route, so this option is incorrect.

The routing table shows a static route to 10.10.20.0/24 via 10.10.10.2, so the route is present. The issue is not a missing route.

The interface is shown as directly connected with a local address, indicating it is up and operational. An administratively down interface would show 'administratively down' in the status.

The output shows 'Gateway of last resort is 10.10.10.2 to network 0.0.0.0', confirming the default route is configured.

The administrative distance should be higher than the primary route's AD (1) to make it less preferred. Setting it to 1 makes it equal, not a backup.

The question explicitly states 'with an administrative distance of 150'. Using 250 is not what was asked, though it would be technically valid.

The default AD is 1, which equals the primary route's AD. This does not create a floating route; both routes are equally preferred.

The specific factual error is that the adjacency is stuck due to timer mismatch, not network type mismatch.

The specific factual error is that the configuration should be applied to R1, not R2, as per the question context.

The specific factual error is that both hello and dead intervals must match; changing only one leaves a mismatch.

The specific factual error: Changing hello intervals is not the standard fix for a point-to-point link not forming adjacency; the network type is the primary issue.

The specific factual error: Setting priority to 0 does not eliminate the DR/BDR election process; it only ensures the router does not participate as DR/BDR.

The specific factual error: The broadcast network type is already the default on Ethernet; the command is redundant and does not address the need for a point-to-point network type.

Preemption is not needed because the current Active router already has the higher priority (110 vs 100). Preemption only becomes relevant when a higher-priority router recovers after a failure and needs to reclaim the Active role. The issue here is routing, not HSRP state stability.

The virtual MAC address is automatically derived from the HSRP group number and is the same for both routers when they are in the same group. R2's local virtual MAC is different because it is used only when R2 becomes Active. The mismatch in the output is normal and does not affect connectivity.

The hello and hold timers are consistent (3 sec hello, 10 sec hold) and are not causing any issues. Adjusting timers would not fix the routing problem. The root cause is the lack of a default route on the Active router.

Configuring different priorities (150 and 50) would force the router with priority 150 to become active regardless of IP address, contradicting the requirement to use the highest IPv4 address for election. HSRP uses priority as the primary criterion; only when priorities are equal does the highest IP address break the tie.

The command 'standby 1 priority 100' is already implied by setting priority 100; it does not enable preemption. With equal priority and no preempt, both routers will remain in standby state indefinitely because HSRP cannot determine an active router without a tiebreaker or preemption. The active router election requires either a priority difference or preempt to resolve the tie.

Configuring different priorities (100 and 50) would make the router with priority 100 active regardless of IP address, which violates the requirement to use the highest IPv4 address for election. The requirement explicitly states that priorities must remain equal so that the highest IP address determines the active router.

This option is incorrect because metrics such as OSPF cost and RIP hop count are not compared across different routing protocols. Administrative distance is the primary factor in route selection between protocols.

This option is incorrect because the dynamic nature of BGP does not override the administrative distance rule. Static routes with AD 1 are always preferred over eBGP routes with AD 20.

This option is incorrect because simplicity of metric calculation (hop count) does not influence route preference. Administrative distance is the deciding factor, and RIP’s higher AD (120) makes it less preferred than OSPF (110).

OSPFv2 does not natively support IPv6; OSPFv3 is required for IPv6 routing.

Link-state advertisements (LSAs) are refreshed every 30 minutes by default, not every 30 seconds.

OSPF router IDs must be unique throughout the OSPF domain; routers in the same area can have different router IDs.

This option incorrectly states that static routes always override dynamic routes. In Cisco routing, static routes only override dynamic routes if their administrative distance is lower. Since the floating static route has a higher AD (150) than OSPF (110), it is not preferred here.

This option is incorrect because load balancing only occurs between routes with equal administrative distances and metrics. Here, the OSPF and floating static routes have different ADs, so only the route with the lower AD is active.

This option is false because OSPF can advertise and learn default routes using the 'default-information originate' command. Therefore, OSPF can carry a default route, making this statement incorrect.

The exhibit shows the static route is configured, so the issue is not that it is missing.

An administrative distance of 200 is appropriate for a floating static route to be less preferred than OSPF (AD 110) but still usable as a backup.

A default route (0.0.0.0/0) does not override a more specific route like 10.10.10.0/24; the longest prefix match rule ensures the specific route is preferred.

The specific factual error is that OSPFv3 uses interface-level configuration, not network statements like OSPFv2 for IPv4.

The specific factual error is that OSPFv3 must be enabled on all interfaces that should participate in the routing process, including loopback interfaces.

The specific factual error is that OSPF router-ids must be unique. Using the same router-id on both routers prevents proper neighbor formation.

This option is incorrect because router hostnames do not affect OSPF neighbor relationships. OSPF adjacency depends on interface-level parameters, not device names, so identical hostnames are not required.

This option is incorrect because converting the link to a trunk is irrelevant for OSPF adjacency on routed interfaces. OSPF operates on Layer 3 interfaces, and trunking is a Layer 2 concept used for VLAN tagging, not required for OSPF neighbor formation.

This option is incorrect because static routes are not necessary for OSPF adjacency. OSPF dynamically discovers neighbors and exchanges routing information without requiring preconfigured static routes.