Juniper JN0-364 Questions & Answers

The broadcast segment has the planned DR and BDR and expected adjacency states after a controlled election event. It would validate a separate OSPF designated router election operation, not the change needed here. Confirm instead that the best route's cumulative OSPF cost selects the approved path and changes predictably when the alternative fails.

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 the best route's cumulative OSPF cost selects the approved path and changes predictably when the alternative fails.

The approved external route is advertised with the intended type and metric while unapproved routes are not redistributed. That establishes OSPF external route export rather than a repaired OSPF interface metric selection path. The reported failure still requires this evidence: the best route's cumulative OSPF cost selects the approved path and changes predictably when the alternative fails.

OSPF point-to-point interfaces do not use a DR or BDR; this differs from a shared multiaccess Ethernet network. That describes OSPF point-to-point topology, whereas the observed symptoms are caused by stable OSPF router identifier; it does not predict the reported behavior.

Although OSPF external route export needs this consideration, the failure at issue has a different cause. OSPF uses the router ID to identify LSA originators; duplicate or unstable IDs undermine link-state identity.

This principle matters when troubleshooting equal-cost forwarding flow hashing, but using it here mistakes a different failure mode for stable OSPF router identifier. The relevant distinction is: OSPF uses the router ID to identify LSA originators; duplicate or unstable IDs undermine link-state identity.

A native VLAN determines how untagged frames are classified on a trunk; inconsistent native mappings can silently bridge the wrong domain. That describes native untagged VLAN drift, whereas the observed symptoms are caused by RSVP path bandwidth admission; it does not predict the reported behavior.

Although MPLS label forwarding table mismatch needs this consideration, the failure at issue has a different cause. RSVP traffic engineering applies resource reservation and constrained path selection, not merely IP shortest-path routing.

Although MPLS label stack bottom bit needs this consideration, the failure at issue has a different cause. RSVP traffic engineering applies resource reservation and constrained path selection, not merely IP shortest-path routing.

The control protects IS-IS route redistribution policy. It does not establish the ongoing IS-IS adjacency circuit level behavior required in this network. IS-IS peers must support a common adjacency level; active Ethernet transport does not compensate for a level mismatch.

This is a useful guard against OSPF external route export, but it is not scoped to the observed IS-IS adjacency circuit level failure. An appropriate test would show that the expected L1 or L2 IS-IS adjacency appears and routing information for the selected level is exchanged.

The control protects IS-IS wide metrics. It does not establish the ongoing IS-IS adjacency circuit level behavior required in this network. IS-IS peers must support a common adjacency level; active Ethernet transport does not compensate for a level mismatch.

This measurement tests stable OSPF router identifier; it cannot distinguish success from failure for the observed RSTP loop protection condition. Loop protection protects non-designated ports against false transition to forwarding when expected BPDUs disappear.

Each VLAN's spanning-tree state selects its planned root and forwarding ports without creating a cross-VLAN loop. It would validate a separate VSTP per-VLAN root choice operation, not the change needed here. Confirm instead that the impacted non-designated port stays protected while BPDUs are absent and returns only after control-plane health is restored.

The approved root remains root despite inferior-site superior-BPDU injection, and the boundary behaves as designed. It would validate a separate RSTP root protection operation, not the change needed here. Confirm instead that the impacted non-designated port stays protected while BPDUs are absent and returns only after control-plane health is restored.

Align MST region name, revision, and VLAN-to-instance mapping across all intended region members. That could help in a case involving MSTP region consistency. This failure instead depends on RSTP alternate port reconvergence; RSTP port roles and rapid state transitions support fast loop-free reconvergence, unlike simply forcing all redundant ports forwarding.

Enable the supported BPDU protection behavior on designated edge ports so unexpected BPDUs trigger a controlled protective response. Its normal acceptance signal would be an unexpected BPDU causes the intended protective state and operations receive a traceable port event. Here the deciding check is different: the alternate port assumes an appropriate forwarding role on failure without allowing simultaneous Layer 2 loops.

Restore IP reachability to the negotiated LDP transport addresses and verify the TCP session and label exchange. This addresses LDP transport address reachability, but the reported symptoms arise from RSTP alternate port reconvergence. For this case, verify instead that the alternate port assumes an appropriate forwarding role on failure without allowing simultaneous Layer 2 loops.

Continuously diff effective import/export policies against approved prefix filters and peer relationships. The monitored boundary differs from IBGP route reflection, so the original weakness might reappear unnoticed. Ordinary iBGP does not readvertise iBGP-learned routes to another iBGP peer; route reflectors provide a controlled exception.

The control protects BGP next-hop reachability. It does not establish the ongoing IBGP route reflection behavior required in this network. Ordinary iBGP does not readvertise iBGP-learned routes to another iBGP peer; route reflectors provide a controlled exception.

Audit MPLS forwarding tables and labeled traffic counters after routing or hardware transitions. That ongoing check is for MPLS label forwarding table mismatch; it would not reliably detect recurrence of IBGP route reflection. Ordinary iBGP does not readvertise iBGP-learned routes to another iBGP peer; route reflectors provide a controlled exception.

MP-BGP requires the appropriate address-family capability and route processing; an Established IPv4 BGP session alone does not carry IPv6 NLRI. That describes multiprotocol BGP IPv6 AFI, whereas the observed symptoms are caused by RSTP root protection; it does not predict the reported behavior.

This principle matters when troubleshooting RSTP alternate port reconvergence, but using it here mistakes a different failure mode for RSTP root protection. The relevant distinction is: root protection blocks acceptance of an unexpected superior root across designated boundary ports; it is not the same as BPDU edge protection.

This principle matters when troubleshooting RSTP loop protection, but using it here mistakes a different failure mode for RSTP root protection. The relevant distinction is: root protection blocks acceptance of an unexpected superior root across designated boundary ports; it is not the same as BPDU edge protection.

Configure and verify compatible protocol graceful-restart capability and planned helper behavior between neighbors. That could help in a case involving graceful restart peer assistance. This failure instead depends on NSR protocol state replication; NSR uses GRES infrastructure while preserving routing protocol state on the backup Routing Engine, avoiding reliance on neighbor restart helpers.

Configure the appropriate EBGP multihop reachability and neighbor addressing, then verify session setup on the intended loopback endpoints. That could help in a case involving EBGP multihop reachability. This failure instead depends on NSR protocol state replication; NSR uses GRES infrastructure while preserving routing protocol state on the backup Routing Engine, avoiding reliance on neighbor restart helpers.

The proposal changes GRES preserves forwarding not protocols; that is not the failure isolated by the facts. It could leave NSR protocol state replication unresolved even if its own test passed. NSR uses GRES infrastructure while preserving routing protocol state on the backup Routing Engine, avoiding reliance on neighbor restart helpers.

Test forwarding, bridge MAC state, and protocol-neighbor continuity separately during redundant Routing Engine failover drills. That ongoing check is for GRES preserves forwarding not protocols; it would not reliably detect recurrence of BFD fast failure detection. BFD provides rapid bidirectional path liveness detection; it triggers routing response but is not by itself a replacement route.

Monitor LACP partner IDs, actor keys, member state, and bundle bandwidth after changes. The monitored boundary differs from BFD fast failure detection, so the original weakness might reappear unnoticed. BFD provides rapid bidirectional path liveness detection; it triggers routing response but is not by itself a replacement route.

Compare OSPF area IDs at both ends of every new inter-router link before production cutover. The monitored boundary differs from BFD fast failure detection, so the original weakness might reappear unnoticed. BFD provides rapid bidirectional path liveness detection; it triggers routing response but is not by itself a replacement route.

This is a useful guard against OSPF designated router election, but it is not scoped to the observed IS-IS LSP database synchronization failure. An appropriate test would show that the two peers converge to consistent current LSP sequence information and compute the same intended topology reachability.

Check interface level settings on both ends during migration and alert on missing expected adjacency levels. That ongoing check is for IS-IS adjacency circuit level; it would not reliably detect recurrence of IS-IS LSP database synchronization. IS-IS LSP sequencing and sequence-number PDUs keep link-state databases synchronized; adjacency status alone does not ensure database parity. Applied here, the relevant facts are: After a transient LAN outage, peers disagree on LSP sequence numbers and one router temporarily lacks the new topology. The question asks which ongoing control would most directly detect or prevent the same failure from recurring.

Capture DIS election and pseudonode observations during shared LAN commissioning and role changes. That ongoing check is for IS-IS LAN designated intermediate system; it would not reliably detect recurrence of IS-IS LSP database synchronization. IS-IS LSP sequencing and sequence-number PDUs keep link-state databases synchronized; adjacency status alone does not ensure database parity.