Free JN0-664 Exam Dumps Preview

The MAC mobility sequence distinguishes competing advertisements for the same MAC address, so the higher sequence resolves conflicting ownership claims after a move. This mobility information is carried with the EVPN MAC/IP Advertisement, which is a Type 2 route. It identifies the newer ownership claim rather than marking a MAC address for unconditional discard.

PIM-SM builds multicast forwarding state only where receivers express interest. A router attached to receivers sends join messages toward its upstream neighbor, extending the distribution tree toward the source or RP. Consequently, multicast traffic is forwarded only along branches requested by downstream routers rather than initially being flooded throughout the network.

To advertise a summarized prefix, the aggregate route must first exist in the routing table. Creating a discard static route for 203.0.113.128/25 installs that summary prefix while preventing traffic loops for destinations without a more-specific route. Because this new summary is a static route rather than a BGP-learned route, the export policy must not restrict matching to protocol bgp; otherwise, the summary route will not be exported to the BGP peer.

OSPF DR and BDR elections are nonpreemptive while the elected routers remain valid. R3's higher priority therefore does not displace either designated router when it joins. It remains a DROther and, on a broadcast network, forms full adjacencies with both the current DR and BDR; adjacencies with other DROther routers remain at the two-way state.

MED is normally compared between routes received from the same neighboring AS. These otherwise equal advertisements come from different ASes, so MED does not provide the next comparison under normal selection. The path-selection process therefore considers the IGP metric to each BGP next hop, preferring the route whose next hop has the lower internal cost. Router ID and peer IP address are later tie-breakers.

R3 advertises the affected prefixes using both legacy IP prefix TLVs with the default metric 63 and extended prefix TLVs, while the established wide-metric environment relies on extended metrics such as 10 and 1000. This mixed behavior indicates that R3 does not have wide metrics enabled consistently. Its metric advertisements therefore do not align with the other routers for equal-cost load balancing.

Rewrite rules operate during egress processing and change the packet's class-of-service marking, such as the DSCP, IP precedence, or MPLS traffic-class value, according to its forwarding class and loss priority. A scheduler controls transmission service, while a policer limits traffic and a forwarding class categorizes it; those components do not perform the required outbound field rewrite.

Return traffic from the Internet is addressed to CE-1's translated public IP, 203.0.113.1, so inet.0 needs a /32 static route whose next-table lookup enters VPN-A.inet.0. In the opposite direction, VPN hosts need Internet reachability; leaking the default route from inet.0 into VPN-A.inet.0 supplies that path without importing all Internet routes.

An NSSA permits its internal ASBR to originate external reachability as an NSSA external advertisement. At the boundary, an ABR translates that information into the normal external form that can be flooded into eligible non-NSSA areas. This mechanism lets locally originated external information leave the NSSA without flooding the original NSSA-specific advertisement unchanged everywhere.

A Partial Sequence Number PDU, or PSNP, lists selected LSP entries rather than the complete link-state database. On a point-to-point exchange it can acknowledge a received LSP, confirming successful delivery. A router can also include an absent or outdated LSP entry in a PSNP to request the missing LSP from its neighbor. CSNPs instead provide broader database summaries for comparison.

The requirement concerns policy applied to VPN routes as they leave the routing instance for remote PE routers. The vrf-export parameter references an export policy, and that policy can attach more than one BGP community or apply other advanced route transformations. A vrf-import policy governs received VPN routes, while a simple vrf-target export value does not provide the same policy flexibility.

A drop profile defines how packet-drop probability changes as a queue fills, providing congestion avoidance before the queue is exhausted. A scheduler references the profile to control drops for its forwarding class. Buffer size changes available storage, priority affects service order, and shaping rate limits transmission, but none of those parameters directly defines the queue-fill-to-drop-probability relationship.

A labeled-unicast route can remain hidden when its next hop must be resolved through VPN routing information. The resolve-vpn parameter permits that resolution under family inet labeled-unicast, allowing the labeled route to become usable. MPLS or OSPF traffic-engineering settings do not address this next-hop resolution condition.

R2 has two otherwise usable paths, but they were learned from different neighboring AS numbers, 65001 and 65003. Ordinary multipath does not make unlike AS paths eligible in this case. Enabling the global BGP multipath multiple-as parameter permits equal paths from different AS peers to participate, after which the existing forwarding-table load-balancing policy can install both next hops.

The vrf-target value provides the target community used in both directions by the routing instance. On import, it identifies BGP VPN routes learned from a remote PE whose target community matches 65100:100. On export, it adds that target community to BGP routes advertised toward remote PE devices, allowing their matching VPN instances to select and import those routes.

Installing both next hops establishes that the BGP control-plane multipath checks succeeded. Forwarding then assigns flows to those next hops using a hash over packet fields; it does not continually equalize byte or packet counters. Different flow sizes, rates, and hash outcomes can therefore produce unequal traffic distribution without invalidating multipath eligibility.