Question 50 Two VRF-Lite customers use the same 10.10.0.0/16 block on one aggregation router; Customer B packets appear in the global routing table. Which technical mechanism best explains the behavior observed in this scenario? An up local interface does not establish end-to-end viability of the PBR-selected next hop. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. EIGRP interface summarization affects advertisements leaving the configured interface, not all neighbors globally. Route-maps apply sequence matching and implicitly deny entries that do not match a permitting clause. ExplanationCorrect Answer B:VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. This explains why the initial condition produces the observed failure. The direct repair is: Place the customer-facing interface in the correct VRF and verify its dedicated routing context and interfaces. Validate through: Query `show ip route vrf` for both tenants and prove that overlap remains isolated under forwarding tests. Other Answers A:An up local interface does not establish end-to-end viability of the PBR-selected next hop. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. C:EIGRP interface summarization affects advertisements leaving the configured interface, not all neighbors globally. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. D:Route-maps apply sequence matching and implicitly deny entries that do not match a permitting clause. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision.
Question 51 Two VRF-Lite customers use the same 10.10.0.0/16 block on one aggregation router; Customer B packets appear in the global routing table. After applying the correction, which verification evidence most directly demonstrates that this issue is resolved? Trace one prefix through both borders and confirm only the intended original source is exported. Inspect route tags in the routing table and prove that a returned tagged prefix is denied while legitimate new prefixes still propagate. Query `show ip route vrf` for both tenants and prove that overlap remains isolated under forwarding tests. Test representative /24 and /26 entries against the prefix list and verify the accepted routing advertisements. ExplanationCorrect Answer C:Query `show ip route vrf` for both tenants and prove that overlap remains isolated under forwarding tests. This checks the affected traffic or control-plane behavior, not merely a generic up/down indicator. The underlying mechanism is: VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. Other Answers A:Trace one prefix through both borders and confirm only the intended original source is exported. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. B:Inspect route tags in the routing table and prove that a returned tagged prefix is denied while legitimate new prefixes still propagate. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. D:Test representative /24 and /26 entries against the prefix list and verify the accepted routing advertisements. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision.
Question 52 Two VRF-Lite customers use the same 10.10.0.0/16 block on one aggregation router; Customer B packets appear in the global routing table. Which lasting design or operational safeguard best prevents this particular issue from recurring? Standardize explicit seed metrics and document route source assumptions for redistribution. Write prefix-policy test cases for exact and more-specific prefixes before deploying modifications. Regression-test the default route-map outcome whenever the match policy is edited. Validate interface-to-VRF bindings against the approved tenant inventory after every cutover. ExplanationCorrect Answer D:Validate interface-to-VRF bindings against the approved tenant inventory after every cutover. This addresses the recurring cause: VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. A targeted acceptance check is: Query `show ip route vrf` for both tenants and prove that overlap remains isolated under forwarding tests. Other Answers A:Standardize explicit seed metrics and document route source assumptions for redistribution. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. B:Write prefix-policy test cases for exact and more-specific prefixes before deploying modifications. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision. C:Regression-test the default route-map outcome whenever the match policy is edited. VRF-Lite maintains separate forwarding and routing tables, permitting overlapping customer prefixes without global collision.
Question 53 A server VLAN is moved into a VRF and its static default route no longer works because it was installed in the global table. Which corrective action most directly resolves the documented failure without suppressing unrelated safeguards? Configure the next-hop route in the tenant VRF with reachability resolved in that VRF. Add an appropriate `ge` and `le` length condition if these more-specific prefixes are truly authorized. Place the customer-facing interface in the correct VRF and verify its dedicated routing context and interfaces. Inspect OSPF path type and cost instead of changing interprotocol administrative distance. ExplanationCorrect Answer A:Configure the next-hop route in the tenant VRF with reachability resolved in that VRF. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. Show the default route and recursive next hop under the tenant VRF, then test client traffic. Other Answers B:Add an appropriate `ge` and `le` length condition if these more-specific prefixes are truly authorized. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. C:Place the customer-facing interface in the correct VRF and verify its dedicated routing context and interfaces. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. D:Inspect OSPF path type and cost instead of changing interprotocol administrative distance. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow.
Question 54 A server VLAN is moved into a VRF and its static default route no longer works because it was installed in the global table. Which technical mechanism best explains the behavior observed in this scenario? Once the route source is OSPF, OSPF's own path-selection rules determine its best candidate before RIB comparison. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. An up local interface does not establish end-to-end viability of the PBR-selected next hop. EIGRP interface summarization affects advertisements leaving the configured interface, not all neighbors globally. ExplanationCorrect Answer B:Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. This explains why the initial condition produces the observed failure. The direct repair is: Configure the next-hop route in the tenant VRF with reachability resolved in that VRF. Validate through: Show the default route and recursive next hop under the tenant VRF, then test client traffic. Other Answers A:Once the route source is OSPF, OSPF's own path-selection rules determine its best candidate before RIB comparison. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. C:An up local interface does not establish end-to-end viability of the PBR-selected next hop. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. D:EIGRP interface summarization affects advertisements leaving the configured interface, not all neighbors globally. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow.
Question 55 A server VLAN is moved into a VRF and its static default route no longer works because it was installed in the global table. After applying the correction, which verification evidence most directly demonstrates that this issue is resolved? Verify BFD session Up state, deliberate forwarding failure detection and corresponding routing reconvergence. Fail remote reachability and verify SLA state, track transitions and payment traffic shifting to the healthy next hop. Show the default route and recursive next hop under the tenant VRF, then test client traffic. Inspect advertisements at the receiving peer and its installed summary route after changing the interface attachment. ExplanationCorrect Answer C:Show the default route and recursive next hop under the tenant VRF, then test client traffic. This checks the affected traffic or control-plane behavior, not merely a generic up/down indicator. The underlying mechanism is: Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. Other Answers A:Verify BFD session Up state, deliberate forwarding failure detection and corresponding routing reconvergence. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. B:Fail remote reachability and verify SLA state, track transitions and payment traffic shifting to the healthy next hop. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. D:Inspect advertisements at the receiving peer and its installed summary route after changing the interface attachment. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow.
Question 56 A server VLAN is moved into a VRF and its static default route no longer works because it was installed in the global table. Which lasting design or operational safeguard best prevents this particular issue from recurring? Standardize explicit seed metrics and document route source assumptions for redistribution. Write prefix-policy test cases for exact and more-specific prefixes before deploying modifications. Require prefix-allocation approval and tests for holes before enabling a broad summary. Include per-VRF route and next-hop checks in every interface migration checklist. ExplanationCorrect Answer D:Include per-VRF route and next-hop checks in every interface migration checklist. This addresses the recurring cause: Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. A targeted acceptance check is: Show the default route and recursive next hop under the tenant VRF, then test client traffic. Other Answers A:Standardize explicit seed metrics and document route source assumptions for redistribution. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. B:Write prefix-policy test cases for exact and more-specific prefixes before deploying modifications. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow. C:Require prefix-allocation approval and tests for holes before enabling a broad summary. Moving an interface into a VRF separates its forwarding from global RIB entries; global static routes do not automatically follow.
Question 57 A dual-homed router forms ordinary routing neighbors but takes many seconds to withdraw an unreachable peer when physical interfaces stay up. Which corrective action most directly resolves the documented failure without suppressing unrelated safeguards? Enable BFD with compatible timers and bind routing sessions to it where both peers support that integration. Use PBR next-hop availability checking or reachability tracking supported by the platform instead of trusting link-up alone. Place the customer-facing interface in the correct VRF and verify its dedicated routing context and interfaces. Use one redistribution owner for the prefix and tag/filter competing external copies at other borders. ExplanationCorrect Answer A:Enable BFD with compatible timers and bind routing sessions to it where both peers support that integration. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. Verify BFD session Up state, deliberate forwarding failure detection and corresponding routing reconvergence. Other Answers B:Use PBR next-hop availability checking or reachability tracking supported by the platform instead of trusting link-up alone. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. C:Place the customer-facing interface in the correct VRF and verify its dedicated routing context and interfaces. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. D:Use one redistribution owner for the prefix and tag/filter competing external copies at other borders. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval.
Question 58 A dual-homed router forms ordinary routing neighbors but takes many seconds to withdraw an unreachable peer when physical interfaces stay up. Which technical mechanism best explains the behavior observed in this scenario? An up local interface does not establish end-to-end viability of the PBR-selected next hop. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. Redistributing the same origin from multiple protocols can cause multiple external candidates and route-feedback hazards. Uncontrolled bidirectional redistribution can reintroduce an already exported route, producing feedback and unstable route selection. ExplanationCorrect Answer B:Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. This explains why the initial condition produces the observed failure. The direct repair is: Enable BFD with compatible timers and bind routing sessions to it where both peers support that integration. Validate through: Verify BFD session Up state, deliberate forwarding failure detection and corresponding routing reconvergence. Other Answers A:An up local interface does not establish end-to-end viability of the PBR-selected next hop. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. C:Redistributing the same origin from multiple protocols can cause multiple external candidates and route-feedback hazards. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. D:Uncontrolled bidirectional redistribution can reintroduce an already exported route, producing feedback and unstable route selection. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval.
Question 59 A dual-homed router forms ordinary routing neighbors but takes many seconds to withdraw an unreachable peer when physical interfaces stay up. After applying the correction, which verification evidence most directly demonstrates that this issue is resolved? Inspect advertisements at the receiving peer and its installed summary route after changing the interface attachment. Compare OSPF route type, area and total cost before showing the selected next hop. Verify BFD session Up state, deliberate forwarding failure detection and corresponding routing reconvergence. Verify the route-map sequence counters and redistributed prefix set with one matched and one previously unmatched approved route. ExplanationCorrect Answer C:Verify BFD session Up state, deliberate forwarding failure detection and corresponding routing reconvergence. This checks the affected traffic or control-plane behavior, not merely a generic up/down indicator. The underlying mechanism is: Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. Other Answers A:Inspect advertisements at the receiving peer and its installed summary route after changing the interface attachment. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. B:Compare OSPF route type, area and total cost before showing the selected next hop. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. D:Verify the route-map sequence counters and redistributed prefix set with one matched and one previously unmatched approved route. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval.
Question 60 A dual-homed router forms ordinary routing neighbors but takes many seconds to withdraw an unreachable peer when physical interfaces stay up. Which lasting design or operational safeguard best prevents this particular issue from recurring? Use nonoverlapping match objects and negative test cases for every source-sensitive policy. Separate intraprotocol metric troubleshooting from interprotocol AD policy decisions. Regression-test the default route-map outcome whenever the match policy is edited. Use approved BFD profiles and avoid untested aggressive timers on constrained links. ExplanationCorrect Answer D:Use approved BFD profiles and avoid untested aggressive timers on constrained links. This addresses the recurring cause: Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. A targeted acceptance check is: Verify BFD session Up state, deliberate forwarding failure detection and corresponding routing reconvergence. Other Answers A:Use nonoverlapping match objects and negative test cases for every source-sensitive policy. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. B:Separate intraprotocol metric troubleshooting from interprotocol AD policy decisions. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval. C:Regression-test the default route-map outcome whenever the match policy is edited. Bidirectional Forwarding Detection detects forwarding-path failures independently of the protocol's ordinary control-plane hello interval.
