Juniper JN0-364 Questions & Answers

This principle matters when troubleshooting multiprotocol BGP IPv6 AFI, but using it here mistakes a different failure mode for IS-IS IPv6 topology TLVs. The relevant distinction is: IS-IS can carry IPv6 topology and prefix information using appropriate TLVs; an IPv4 route table is not a substitute.

This principle matters when troubleshooting MPLS label push swap pop, but using it here mistakes a different failure mode for IS-IS IPv6 topology TLVs. The relevant distinction is: IS-IS can carry IPv6 topology and prefix information using appropriate TLVs; an IPv4 route table is not a substitute.

Although IPv6 neighbor discovery filtering needs this consideration, the failure at issue has a different cause. IS-IS can carry IPv6 topology and prefix information using appropriate TLVs; an IPv4 route table is not a substitute.

Apply a scoped OSPF export policy to originate only the approved active source prefix and confirm the receiving routers learn it. That could help in a case involving OSPF external route export. This failure instead depends on stable OSPF router identifier; OSPF uses the router ID to identify LSA originators; duplicate or unstable IDs undermine link-state identity.

The proposal changes OSPF interface metric selection; that is not the failure isolated by the facts. It could leave stable OSPF router identifier unresolved even if its own test passed. OSPF uses the router ID to identify LSA originators; duplicate or unstable IDs undermine link-state identity.

Keep GRES for forwarding continuity and enable the appropriate supported NSB for bridging or NSR or graceful restart for routing sessions as required. Its normal acceptance signal would be A controlled Routing Engine switchover retains forwarding and the planned bridge or routing state without unexpected protocol resets. Here the deciding check is different: every router has a distinct planned router ID and the LSDB tracks the appropriate originating router consistently.

Test tunnel path MTU and fragmentation behavior with realistic payload sizes after transport changes. That ongoing check is for GRE tunnel path MTU; it would not reliably detect recurrence of GRE confidentiality limitation. GRE provides encapsulation and protocol carriage but does not inherently supply confidentiality or cryptographic integrity. Applied here, the relevant facts are: Security auditors observe readable payloads captured on a GRE underlay because no separate encryption protects the packets. The question asks which ongoing control would most directly detect or prevent the same failure from recurring.

The control protects GRE recursive route avoidance. It does not establish the ongoing GRE confidentiality limitation behavior required in this network. GRE provides encapsulation and protocol carriage but does not inherently supply confidentiality or cryptographic integrity. Applied here, the relevant facts are: Security auditors observe readable payloads captured on a GRE underlay because no separate encryption protects the packets. The question asks which ongoing control would most directly detect or prevent the same failure from recurring.

Compare intended LDP interface coverage against active discovery neighbors after link additions. The monitored boundary differs from GRE confidentiality limitation, so the original weakness might reappear unnoticed. GRE provides encapsulation and protocol carriage but does not inherently supply confidentiality or cryptographic integrity.

The control protects IBGP route reflection. It does not establish the ongoing RSVP PATH and RESV signaling behavior required in this network. RSVP-TE establishes LSP state through forward PATH and reverse RESV processing; one-way PATH reception is insufficient.

This is a useful guard against LDP label binding completeness, but it is not scoped to the observed RSVP PATH and RESV signaling failure. An appropriate test would show that the LSP shows a completed RSVP reservation and an operational signaled path through intended hops.

Audit explicit segment lists against intended physical-hop constraints before deployment. The monitored boundary differs from RSVP PATH and RESV signaling, so the original weakness might reappear unnoticed. RSVP-TE establishes LSP state through forward PATH and reverse RESV processing; one-way PATH reception is insufficient.

Account for GRE/IP header overhead in tunnel MTU and path-MTU handling, then test large representative packets. Its normal acceptance signal would be maximum expected encapsulated packets cross the tunnel without fragmentation blackholes or oversized drop counters. Here the deciding check is different: the adjacency remains Full over successive dead intervals without periodic neighbor expiration.

Resolve the underlying link MTU mismatch and validate successful database description exchange rather than masking the check. This addresses OSPF MTU negotiation, but the reported symptoms arise from OSPF hello and dead timers. For this case, verify instead that the adjacency remains Full over successive dead intervals without periodic neighbor expiration.

Apply a scoped OSPF export policy to originate only the approved active source prefix and confirm the receiving routers learn it. That could help in a case involving OSPF external route export. This failure instead depends on OSPF hello and dead timers; OSPF neighbor formation requires compatible hello and dead timers; link-layer carrier does not override timer mismatch.

The check is meaningful for RIB group route sharing, but it does not prove that static route next-hop resolution was repaired. Junos installs a usable route only after next-hop resolution and route selection; a configured static statement alone does not guarantee active forwarding.

Maximum expected encapsulated packets cross the tunnel without fragmentation blackholes or oversized drop counters. That establishes GRE tunnel path MTU rather than a repaired static route next-hop resolution path. The reported failure still requires this evidence: the intended destination appears as an active route with a resolvable next hop in the routing table and forwarding table.

The affected customer's lookup uses the intended instance RIB and reaches only the destinations deliberately made available to that instance. It would validate a separate routing instance separation operation, not the change needed here. Confirm instead that the intended destination appears as an active route with a resolvable next hop in the routing table and forwarding table.

Packets to the remote outer endpoint resolve through an ordinary underlay route and GRE probes reach the peer. It would validate a separate GRE endpoint underlay routing operation, not the change needed here. Confirm instead that packet traces follow the specified adjacency rather than merely the IGP shortest path to a node SID.

This measurement tests LDP label binding completeness; it cannot distinguish success from failure for the observed segment routing adjacency SID condition. An adjacency SID steers traffic across a specific link, whereas a prefix SID steers toward a node or prefix along shortest paths.

Incoming labels resolve to valid outgoing label operations and interfaces, and data-plane counters show successful forwarding. That establishes MPLS label forwarding table mismatch rather than a repaired segment routing adjacency SID path. The reported failure still requires this evidence: packet traces follow the specified adjacency rather than merely the IGP shortest path to a node SID.

Although virtual-switch instance isolation needs this consideration, the failure at issue has a different cause. Access ports and trunk ports have different VLAN tagging and membership behaviors; link-up state does not make the modes equivalent.

Provider tag stacking adds frame overhead; an unchanged link MTU may reject frames that previously fitted untagged. Those conditions do not account for the specific VLAN access trunk distinction problem reported by Oakline Utilities.

This principle matters when troubleshooting IS-IS LAN designated intermediate system, but using it here mistakes a different failure mode for VLAN access trunk distinction. The relevant distinction is: access ports and trunk ports have different VLAN tagging and membership behaviors; link-up state does not make the modes equivalent.

Loop protection protects non-designated ports against false transition to forwarding when expected BPDUs disappear. That describes RSTP loop protection, whereas the observed symptoms are caused by GRES preserves forwarding not protocols; it does not predict the reported behavior.

This principle matters when troubleshooting graceful restart peer assistance, but using it here mistakes a different failure mode for GRES preserves forwarding not protocols. The relevant distinction is: GRES preserves forwarding and kernel state but does not by itself preserve all routing or bridging state; NSB targets bridge continuity and NSR or graceful restart addresses routing continuity.

NSR uses GRES infrastructure while preserving routing protocol state on the backup Routing Engine, avoiding reliance on neighbor restart helpers. That describes NSR protocol state replication, whereas the observed symptoms are caused by GRES preserves forwarding not protocols; it does not predict the reported behavior. Applied here, the relevant facts are: A dual-RE router keeps forwarding through a GRES switchover but loses routing neighbors because protocol state was not preserved. The question asks which networking principle most accurately explains the observed failure.

The best route's cumulative OSPF cost selects the approved path and changes predictably when the alternative fails. That establishes OSPF interface metric selection rather than a repaired OSPF designated router election path. The reported failure still requires this evidence: the broadcast segment has the planned DR and BDR and expected adjacency states after a controlled election event.

This measurement tests IS-IS NET and system ID; it cannot distinguish success from failure for the observed OSPF designated router election condition. OSPF broadcast networks elect a DR and BDR; raising priority does not automatically preempt an already elected DR.

The check is meaningful for OSPF MTU negotiation, but it does not prove that OSPF designated router election was repaired. OSPF broadcast networks elect a DR and BDR; raising priority does not automatically preempt an already elected DR.

This principle matters when troubleshooting GRE tunnel path MTU, but using it here mistakes a different failure mode for RSTP alternate port reconvergence. The relevant distinction is: RSTP port roles and rapid state transitions support fast loop-free reconvergence, unlike simply forcing all redundant ports forwarding.

VSTP maintains spanning-tree behavior per VLAN; one VLAN's root decision does not automatically govern every VLAN. That describes VSTP per-VLAN root choice, whereas the observed symptoms are caused by RSTP alternate port reconvergence; it does not predict the reported behavior.

Although MSTP region consistency needs this consideration, the failure at issue has a different cause. RSTP port roles and rapid state transitions support fast loop-free reconvergence, unlike simply forcing all redundant ports forwarding.