Juniper JN0-650 Practice Test 19
Question 180
An import policy unexpectedly accepts a long private prefix because an early term matches broadly. Select TWO statements that correctly combine the Junos BGP policy term matching implementation, its evidence, or its governing principle.
- Only sanctioned routes pass the policy and term counters identify the decision.
- Put a filter name in the peer description and assume it becomes an active policy.
- Implement ordered Junos policy terms with prefix match and explicit accept or reject decisions.
- Restore valid next-hop reachability without indiscriminately accepting broken routes.
- Examine and apply origin attribute handling only within an intentional routing-policy decision.
Explanation
Correct Answers
A:Only sanctioned routes pass the policy and term counters identify the decision. This is direct observable evidence for Junos BGP policy term matching.
C:Implement ordered Junos policy terms with prefix match and explicit accept or reject decisions. This is the intended implementation action for Junos BGP policy term matching.
Incorrect Answers
B:Put a filter name in the peer description and assume it becomes an active policy. This would not be an appropriate Junos BGP policy term matching decision. An overly general term can prevent subsequent protective terms from being reached.
D:Restore valid next-hop reachability without indiscriminately accepting broken routes. This belongs to BGP next-hop reachability hidden route, not the specified Junos BGP policy term matching operation. Junos routing policy evaluates ordered terms and control-flow actions.
E:Examine and apply origin attribute handling only within an intentional routing-policy decision. This belongs to BGP origin attribute influence, not the specified Junos BGP policy term matching operation. Junos routing policy evaluates ordered terms and control-flow actions.
Question 181
During an operational risk review, this situation is reported: A third-party phone accepts network policy VLAN ID but ignores the advertised priority. If the underlying control is neglected, which failure would MOST directly follow?
- Assuming any PoE-capable port supplies every device's requested wattage is unsafe.
- An incorrect priority policy can deprioritize voice even on the right VLAN.
- Failure to reauthorize after recovery can leave endpoints overprivileged or stuck in fallback.
- A physical pair or overload fault can stop power before any voice VLAN setup matters.
Explanation
Correct Answer
B:An incorrect priority policy can deprioritize voice even on the right VLAN. LLDP-MED can convey voice network policy including VLAN and priority information. A useful corrective investigation is to inspect LLDP-MED network policy fields and captured 802.1Q priority bits.
Incorrect Answers
A:Assuming any PoE-capable port supplies every device's requested wattage is unsafe. This is a PoE class discovery and allocation failure pattern, not the primary LLDP-MED voice priority signaling failure in this case. LLDP-MED can convey voice network policy including VLAN and priority information.
C:Failure to reauthorize after recovery can leave endpoints overprivileged or stuck in fallback. This is a RADIUS server-fail remediation and reauthentication failure pattern, not the primary LLDP-MED voice priority signaling failure in this case. LLDP-MED can convey voice network policy including VLAN and priority information.
D:A physical pair or overload fault can stop power before any voice VLAN setup matters. This is a PoE fault isolation and cable pair failure pattern, not the primary LLDP-MED voice priority signaling failure in this case. LLDP-MED can convey voice network policy including VLAN and priority information.
Question 182
A dual-stack branch forms IPv4 OSPF neighbors but IPv6 route propagation remains broken. Which next investigation or correction is MOST appropriate?
- Verify per-interface network type and Hello processing at both endpoints.
- Compare show ospf neighbor with show ospf3 neighbor and inet versus inet6 routes.
- Inspect detailed neighbor state and interface MTU on both systems.
- Disable OSPFv3 because OSPFv2 already carries every IPv6 prefix by default.
Explanation
Correct Answer
B:Compare show ospf neighbor with show ospf3 neighbor and inet versus inet6 routes. This checks whether both IPv4 and IPv6 routes appear via their configured protocols independently.
Incorrect Answers
A:Verify per-interface network type and Hello processing at both endpoints. That check applies chiefly to OSPF point-to-point network type, not the current OSPFv2 versus OSPFv3 operations issue. OSPFv2 and OSPFv3 have related SPF logic but separate protocol and address-family configuration.
C:Inspect detailed neighbor state and interface MTU on both systems. That check applies chiefly to OSPF interface MTU mismatch, not the current OSPFv2 versus OSPFv3 operations issue. OSPFv2 and OSPFv3 have related SPF logic but separate protocol and address-family configuration.
D:Disable OSPFv3 because OSPFv2 already carries every IPv6 prefix by default. That bypass leaves the OSPFv2 versus OSPFv3 operations issue unresolved. A healthy IPv4 neighbor is not proof of IPv6 adjacency or prefix reachability.
Question 183
A PIM neighbor receives group joins from an unapproved network segment. Which next investigation or correction is MOST appropriate?
- Rename the multicast group InternalOnly and assume routers automatically enforce a security boundary.
- Review RP election discovery information and group-range reachability.
- Verify denied-group counters and successful forwarding for approved test groups.
- Trace multicast forwarding entries hop by hop toward source or RP.
Explanation
Correct Answer
C:Verify denied-group counters and successful forwarding for approved test groups. This checks whether authorized groups forward while disallowed group joins or advertisements are rejected.
Incorrect Answers
A:Rename the multicast group InternalOnly and assume routers automatically enforce a security boundary. That bypass leaves the Multicast policy group scoping issue unresolved. An unrestricted policy can carry sensitive multicast into unintended domains.
B:Review RP election discovery information and group-range reachability. That check applies chiefly to PIM RP discovery and bootstrap mapping, not the current Multicast policy group scoping issue. Multicast routing policy or scoping constrains distribution without changing sender addresses.
D:Trace multicast forwarding entries hop by hop toward source or RP. That check applies chiefly to PIM join prune forwarding path, not the current Multicast policy group scoping issue. Multicast routing policy or scoping constrains distribution without changing sender addresses.
Question 184
An access-to-distribution link passes management traffic but drops a tagged production VLAN. Which next investigation or correction is MOST appropriate?
- Inspect interface ethernet-switching configuration and VLAN counters on both ends.
- Assign an IPv4 default route and assume the missing VLAN is automatically allowed on the trunk.
- Capture target control frames and verify each allowed protocol end to end.
- Inspect ingress and egress double-tag format and switch VLAN translation state.
Explanation
Correct Answer
A:Inspect interface ethernet-switching configuration and VLAN counters on both ends. This checks whether expected tagged VLAN traffic traverses the trunk while unapproved VLANs remain blocked.
Incorrect Answers
B:Assign an IPv4 default route and assume the missing VLAN is automatically allowed on the trunk. That bypass leaves the 802.1Q trunk allowed VLANs issue unresolved. Missing tagged membership creates silent Layer 2 reachability gaps.
C:Capture target control frames and verify each allowed protocol end to end. That check applies chiefly to L2PT protocol selection and isolation, not the current 802.1Q trunk allowed VLANs issue. IEEE 802.1Q tags distinguish VLAN traffic across a common trunk.
D:Inspect ingress and egress double-tag format and switch VLAN translation state. That check applies chiefly to QinQ service VLAN outer tag, not the current 802.1Q trunk allowed VLANs issue. IEEE 802.1Q tags distinguish VLAN traffic across a common trunk.
Question 185
A route reflector fails to propagate one client route because client and nonclient roles are wrong. Which next investigation or correction is MOST appropriate?
- Configure the route reflector as an OSPF DR and assume BGP reflection is enabled.
- Inspect reflected path originator ID cluster list and neighbor client roles.
- Inspect negotiated families and show route table inet.0 protocol bgp.
- Examine suppression status penalty decay and recovery timing.
Explanation
Correct Answer
B:Inspect reflected path originator ID cluster list and neighbor client roles. This checks whether client routes are reflected as intended without iBGP full mesh or reflection loops.
Incorrect Answers
A:Configure the route reflector as an OSPF DR and assume BGP reflection is enabled. That bypass leaves the BGP route reflection cluster issue unresolved. Incorrect reflection topology can hide otherwise valid internal paths.
C:Inspect negotiated families and show route table inet.0 protocol bgp. That check applies chiefly to BGP NLRI IPv4 unicast inet family, not the current BGP route reflection cluster issue. BGP route reflection reduces iBGP full-mesh needs using originator and cluster loop controls.
D:Examine suppression status penalty decay and recovery timing. That check applies chiefly to BGP route damping flap penalty, not the current BGP route reflection cluster issue. BGP route reflection reduces iBGP full-mesh needs using originator and cluster loop controls.
Question 186
An NSSA ABR fails to propagate an intended locally originated external destination into the backbone. Select TWO statements that correctly combine the OSPF NSSA type-seven translation implementation, its evidence, or its governing principle.
- Use a consistent OSPF reference-bandwidth policy across the intended routing domain.
- Configure an appropriate NSSA design and verify type-7 external translation where applicable.
- Assume a type-7 LSA is a BGP VPN label advertisement.
- Tune eligible OSPF interface priority and plan an explicit election event where required.
- NSSA-local external reachability is advertised as expected into other areas.
Explanation
Correct Answers
B:Configure an appropriate NSSA design and verify type-7 external translation where applicable. This is the intended implementation action for OSPF NSSA type-seven translation.
E:NSSA-local external reachability is advertised as expected into other areas. This is direct observable evidence for OSPF NSSA type-seven translation.
Incorrect Answers
A:Use a consistent OSPF reference-bandwidth policy across the intended routing domain. This belongs to OSPF reference bandwidth and high-speed links, not the specified OSPF NSSA type-seven translation operation. NSSA can carry type-7 external LSAs and ABRs may translate them to type-5.
C:Assume a type-7 LSA is a BGP VPN label advertisement. This would not be an appropriate OSPF NSSA type-seven translation decision. Treating NSSA redistribution as a normal stub area can suppress required external routes.
D:Tune eligible OSPF interface priority and plan an explicit election event where required. This belongs to OSPF designated router election broadcast LAN, not the specified OSPF NSSA type-seven translation operation. NSSA can carry type-7 external LSAs and ABRs may translate them to type-5.
Question 187
A dual-stack interface has an IPv4 DSCP classifier but no equivalent IPv6 treatment. Which technical principle BEST explains the Junos IPv6 DSCP classifier family decision?
- 802.1p PCP bits are distinct from IP DSCP and may require explicit mapping.
- A policer meters traffic and may drop or remark traffic exceeding its limits.
- MVRP learned registrations have different lifecycle from explicitly configured static VLAN memberships.
- Packet classification must account for the correct protocol header family.
Explanation
Correct Answer
D:Packet classification must account for the correct protocol header family. In this situation, the relevant action is to apply appropriate supported IPv6 DSCP classification on the relevant ingress family.
Incorrect Answers
A:802.1p PCP bits are distinct from IP DSCP and may require explicit mapping. That principle is related to IEEE 802.1p CoS rewrite on Ethernet, not the main Junos IPv6 DSCP classifier family choice. Assuming an IPv4-only classifier handles all IPv6 traffic may cause inconsistent QoS.
B:A policer meters traffic and may drop or remark traffic exceeding its limits. That principle is related to Junos ingress policer rate limit, not the main Junos IPv6 DSCP classifier family choice. Assuming an IPv4-only classifier handles all IPv6 traffic may cause inconsistent QoS.
C:MVRP learned registrations have different lifecycle from explicitly configured static VLAN memberships. That principle is related to MVRP static versus dynamic registration, not the main Junos IPv6 DSCP classifier family choice. Assuming an IPv4-only classifier handles all IPv6 traffic may cause inconsistent QoS.
Question 188
A new ABR introduces external advertisements into an area intended to be stub. Which next investigation or correction is MOST appropriate?
- Check area capabilities and LSDB LSA types at the ABR and branch.
- Inspect NSSA LSAs and translated external entries at the ABR.
- Configure only a BGP export policy and claim the OSPF area became stub.
- Inspect route hidden reason protocol database and configured policy chains.
Explanation
Correct Answer
A:Check area capabilities and LSDB LSA types at the ABR and branch. This checks whether the stub receives an appropriate default or interarea reachability without external type-5 flooding.
Incorrect Answers
B:Inspect NSSA LSAs and translated external entries at the ABR. That check applies chiefly to OSPF NSSA type-seven translation, not the current OSPF stub area external LSA suppression issue. OSPF stub areas restrict external AS-external advertisements and require compatible area flags.
C:Configure only a BGP export policy and claim the OSPF area became stub. That bypass leaves the OSPF stub area external LSA suppression issue unresolved. Mixing stub and normal-area settings prevents correct neighbor establishment.
D:Inspect route hidden reason protocol database and configured policy chains. That check applies chiefly to OSPF routing policy import filtering, not the current OSPF stub area external LSA suppression issue. OSPF stub areas restrict external AS-external advertisements and require compatible area flags.
Question 189
Guest rooms share one IP subnet but endpoints must not talk directly to each other. Which configuration or operational step BEST meets the stated requirement?
- Set a VLAN name Private and assume all member ports become isolated automatically.
- Reorder policy terms so specific supported VLAN matches precede broad fallback actions.
- Assign supported isolated secondary VLAN roles and permitted promiscuous uplink mapping.
- Combine required static VLAN membership with deliberate dynamic registration policy.
Explanation
Correct Answer
C:Assign supported isolated secondary VLAN roles and permitted promiscuous uplink mapping. Private VLAN isolation provides Layer 2 separation within a shared primary VLAN. The expected validation is that isolated endpoints reach the intended shared gateway but not peer isolated ports.
Incorrect Answers
A:Set a VLAN name Private and assume all member ports become isolated automatically. This is a risky or ineffective shortcut for Private VLAN isolated port separation. Treating primary VLAN membership alone as isolation allows undesired peer traffic.
B:Reorder policy terms so specific supported VLAN matches precede broad fallback actions. This addresses Filter-based VLAN rule precedence rather than the required Private VLAN isolated port separation decision. Private VLAN isolation provides Layer 2 separation within a shared primary VLAN.
D:Combine required static VLAN membership with deliberate dynamic registration policy. This addresses MVRP static versus dynamic registration rather than the required Private VLAN isolated port separation decision. Private VLAN isolation provides Layer 2 separation within a shared primary VLAN.
Question 190
A dual-stack branch forms IPv4 OSPF neighbors but IPv6 route propagation remains broken. Which technical principle BEST explains the OSPFv2 versus OSPFv3 operations decision?
- OSPFv2 and OSPFv3 have related SPF logic but separate protocol and address-family configuration.
- OSPF DR election on broadcast networks is priority based and nonpreemptive under normal conditions.
- OSPF stub areas restrict external AS-external advertisements and require compatible area flags.
- Guest VLAN authorizes limited access for eligible unauthenticated clients.
Explanation
Correct Answer
A:OSPFv2 and OSPFv3 have related SPF logic but separate protocol and address-family configuration. In this situation, the relevant action is to troubleshoot OSPF and OSPFv3 sessions and tables as distinct address-family contexts.
Incorrect Answers
B:OSPF DR election on broadcast networks is priority based and nonpreemptive under normal conditions. That principle is related to OSPF designated router election broadcast LAN, not the main OSPFv2 versus OSPFv3 operations choice. A healthy IPv4 neighbor is not proof of IPv6 adjacency or prefix reachability.
C:OSPF stub areas restrict external AS-external advertisements and require compatible area flags. That principle is related to OSPF stub area external LSA suppression, not the main OSPFv2 versus OSPFv3 operations choice. A healthy IPv4 neighbor is not proof of IPv6 adjacency or prefix reachability.
D:Guest VLAN authorizes limited access for eligible unauthenticated clients. That principle is related to Guest VLAN for unauthenticated clients, not the main OSPFv2 versus OSPFv3 operations choice. A healthy IPv4 neighbor is not proof of IPv6 adjacency or prefix reachability.
