Juniper JN0-364 Questions & Answers

The check is meaningful for GRE tunnel path MTU, but it does not prove that NSR protocol state replication was repaired. NSR uses GRES infrastructure while preserving routing protocol state on the backup Routing Engine, avoiding reliance on neighbor restart helpers.

A controlled Routing Engine switchover retains forwarding and the planned bridge or routing state without unexpected protocol resets. That establishes GRES preserves forwarding not protocols rather than a repaired NSR protocol state replication path. The reported failure still requires this evidence: during a controlled primary RE loss, eligible routing adjacencies continue using state maintained by the backup RE.

During a controlled routing restart, participating neighbors retain forwarding state only for the permitted grace interval and then converge correctly. It would validate a separate graceful restart peer assistance operation, not the change needed here. Confirm instead that during a controlled primary RE loss, eligible routing adjacencies continue using state maintained by the backup RE.

This is a useful guard against IBGP route reflection, but it is not scoped to the observed BGP next-hop reachability failure. An appropriate test would show that the received BGP route has a resolvable next hop, becomes eligible, and installs usable forwarding state.

The control protects BGP import export control. It does not establish the ongoing BGP next-hop reachability behavior required in this network. A BGP path is not usable merely because UPDATE is received; next-hop resolution is required for route selection and installation.

This is a useful guard against native untagged VLAN drift, but it is not scoped to the observed BGP next-hop reachability failure. An appropriate test would show that the received BGP route has a resolvable next hop, becomes eligible, and installs usable forwarding state.

The check is meaningful for stable OSPF router identifier, but it does not prove that OSPF external route export was repaired. OSPF external redistribution is controlled by export policy; stable IGP neighbor state does not imply arbitrary static or direct routes are advertised.

This measurement tests provider bridging MTU overhead; it cannot distinguish success from failure for the observed OSPF external route export condition. OSPF external redistribution is controlled by export policy; stable IGP neighbor state does not imply arbitrary static or direct routes are advertised.

The two peers form a Full point-to-point adjacency without a broadcast-segment DR election. That establishes OSPF point-to-point topology rather than a repaired OSPF external route export path. The reported failure still requires this evidence: the approved external route is advertised with the intended type and metric while unapproved routes are not redistributed.

Enable and verify negotiated IPv6-unicast capability and matching route-policy handling on the BGP peers. This addresses multiprotocol BGP IPv6 AFI, but the reported symptoms arise from OSPFv3 IPv6 neighbor reachability. For this case, verify instead that the expected OSPFv3 neighbor reaches Full and IPv6 routes appear with intended next hops.

Verify full label stack ordering and bottom-of-stack indication on the encapsulated service path. Its normal acceptance signal would be traces show the transport label above the service label with bottom-of-stack marked only on the last label. Here the deciding check is different: the expected OSPFv3 neighbor reaches Full and IPv6 routes appear with intended next hops.

The proposal changes IPv6 neighbor discovery filtering; that is not the failure isolated by the facts. It could leave OSPFv3 IPv6 neighbor reachability unresolved even if its own test passed. OSPFv3 provides OSPF routing for IPv6; successful IPv4 OSPFv2 peering does not establish an IPv6 adjacency.

Although OSPF point-to-point topology needs this consideration, the failure at issue has a different cause. Control-plane LSP state and data-plane label forwarding entries are separate checks; an Up session does not prove the FIB is correct.

Although LDP label binding completeness needs this consideration, the failure at issue has a different cause. Control-plane LSP state and data-plane label forwarding entries are separate checks; an Up session does not prove the FIB is correct.

This principle matters when troubleshooting penultimate hop popping, but using it here mistakes a different failure mode for MPLS label forwarding table mismatch. The relevant distinction is: control-plane LSP state and data-plane label forwarding entries are separate checks; an Up session does not prove the FIB is correct.

BGP peers validate AS identity during OPEN negotiation; transport reachability by itself does not establish a valid BGP session. That describes BGP ASN and OPEN negotiation, whereas the observed symptoms are caused by BGP communities and routing policy; it does not predict the reported behavior.

Although LDP label binding completeness needs this consideration, the failure at issue has a different cause. BGP communities provide policy metadata for grouping routes; they have no forwarding effect unless a matching policy interprets them.

This principle matters when troubleshooting EBGP multihop reachability, but using it here mistakes a different failure mode for BGP communities and routing policy. The relevant distinction is: BGP communities provide policy metadata for grouping routes; they have no forwarding effect unless a matching policy interprets them.

Give each router a unique system ID and a NET whose area portion matches intended Level 1 membership. This addresses IS-IS NET and system ID, but the reported symptoms arise from LDP label binding completeness. For this case, verify instead that the forwarding table has a valid outgoing label for the selected next hop and labeled traffic reaches the intended prefix.

Enable appropriate LDP interface discovery and verify discovery hellos and eventual neighbor session state. This addresses LDP neighbor discovery, but the reported symptoms arise from LDP label binding completeness. For this case, verify instead that the forwarding table has a valid outgoing label for the selected next hop and labeled traffic reaches the intended prefix.

Verify full label stack ordering and bottom-of-stack indication on the encapsulated service path. That could help in a case involving MPLS label stack bottom bit. This failure instead depends on LDP label binding completeness; LDP supplies label bindings for eligible FECs; IP reachability without a usable label binding does not prove labeled forwarding.

LDP uses discovery messages on enabled interfaces before exchanging label mappings; IGP reachability alone does not start LDP. That describes LDP neighbor discovery, whereas the observed symptoms are caused by segment routing adjacency SID; it does not predict the reported behavior.

Penultimate-hop popping can remove an outer transport label before the egress, reducing egress label processing. Those conditions do not account for the specific segment routing adjacency SID problem reported by Elmbridge Networks.

Graceful restart depends on protocol restart and helper behavior; it is not identical to copying live routing protocol state to a backup Routing Engine. That describes graceful restart peer assistance, whereas the observed symptoms are caused by segment routing adjacency SID; it does not predict the reported behavior.

The control protects MPLS label push swap pop. It does not establish the ongoing LDP transport address reachability behavior required in this network. LDP discovery and session setup are distinct; a transport TCP connection must be reachable after hello discovery.

Test double-tag preservation and S-tag membership on both ends of each provider handoff. That ongoing check is for provider Q-in-Q tagging; it would not reliably detect recurrence of LDP transport address reachability. LDP discovery and session setup are distinct; a transport TCP connection must be reachable after hello discovery.

Alert on missing LDP label mappings for required FECs after peer resets and topology changes. That ongoing check is for LDP label binding completeness; it would not reliably detect recurrence of LDP transport address reachability. LDP discovery and session setup are distinct; a transport TCP connection must be reachable after hello discovery.

The prefix SID is advertised and all ingress routers compute consistent transport label behavior for the node destination. It would validate a separate segment routing prefix SID operation, not the change needed here. Confirm instead that the forwarding table has a valid outgoing label for the selected next hop and labeled traffic reaches the intended prefix.

The check is meaningful for GRE endpoint underlay routing, but it does not prove that LDP label binding completeness was repaired. LDP supplies label bindings for eligible FECs; IP reachability without a usable label binding does not prove labeled forwarding.

The check is meaningful for MPLS label forwarding table mismatch, but it does not prove that LDP label binding completeness was repaired. LDP supplies label bindings for eligible FECs; IP reachability without a usable label binding does not prove labeled forwarding.

This principle matters when troubleshooting filter-based forwarding table selection, but using it here mistakes a different failure mode for aggregate route contributor. The relevant distinction is: an aggregate route is conditional on active contributing routes and normally uses a discard or reject next hop to avoid creating a forwarding loop.

VRRP coordinates an active virtual default gateway among participating routers, unlike independent physical interface addresses. That describes VRRP virtual gateway failover, whereas the observed symptoms are caused by aggregate route contributor; it does not predict the reported behavior.

Equal routing candidates do not prove the forwarding engine is using ECMP; Junos load-balancing policy and flow hashing determine installed next hops. Those conditions do not account for the specific aggregate route contributor problem reported by Northshore Digital.