[Oct 16, 2023] JN0-664 Ultimate Study Guide - RealValidExam
Ultimate Guide to Prepare JN0-664 Certification Exam for JNCIP-SP in 2023
NEW QUESTION # 39
Exhibit
CE-1 and CE-2 are part of a VPLS called Customer1 No connectivity exists between CE-1 and CE-2. In the process of troubleshooting, you notice PE-1 is not learning any routes for this VPLS from PE-2, and PE-2 is not learning any routes for this VPLS from PE-1.
- A. The no-tunnel-services statement should be deleted on both PEs.
- B. The route target must match on PE-1 and PE-2.
- C. The instance type should be changed to I2vpn.
- D. The route distinguisher must match on PE-1 and PE-2.
Answer: B
Explanation:
Explanation
VPLS is a technology that provides Layer 2 VPN services over an MPLS network. VPLS uses BGP as its control protocol to exchange VPN membership information between PE routers. The route target is a BGP extended community attribute that identifies which VPN a route belongs to. The route target must match on PE routers that participate in the same VPLS instance, otherwise they will not accept or advertise routes for that VPLS.
NEW QUESTION # 40
Exhibit
You want to use both links between R1 and R2 Because of the bandwidth difference between the two links, you must ensure that the links are used as much as possible.
Which action will accomplish this goal?
- A. Ensure that the metric-out parameter on the Gigabit Ethernet interface is higher than the 10 Gigibit Ethernet interface.
- B. Disable multipath.
- C. Define a policy to tag routes with the appropriate bandwidth community.
- D. Enable per-prefix load balancing.
Answer: D
Explanation:
Explanation
VPLS is a Layer 2 VPN technology that allows multiple sites to connect over a shared IP/MPLS network as if they were on the same LAN. VPLS tunnels can be signaled using either Label Distribution Protocol (LDP) or Border Gateway Protocol (BGP). In this question, we have two links between R1 and R2 with different bandwidths (10 Gbps and 1 Gbps). We want to use both links as much as possible for VPLS traffic. To achieve this, we need to enable per-prefix load balancing on both routers. Per-prefix load balancing is a feature that allows a router to distribute traffic across multiple equal-cost or unequal-cost paths based on the destination prefix of each packet. This improves the utilization of multiple links and provides better load sharing than per-flow load balancing, which distributes traffic based on a hash of source and destination addresses4. Per-prefix load balancing can be enabled globally or per interface using the load-balance per-packet command.
NEW QUESTION # 41
Exhibit
Which two statements about the configuration shown in the exhibit are correct? (Choose two.)
- A. This VPN connects customer sites that use different AS numbers.
- B. A Layer 3 VPN is configured.
- C. This VPN connects customer sites that use the same AS number
- D. A Layer 2 VPN is configured.
Answer: A,B
Explanation:
Explanation
The configuration shown in the exhibit is for a Layer 3 VPN that connects customer sites that use different AS numbers. A Layer 3 VPN is a type of VPN that uses MPLS labels to forward packets across a provider network and BGP to exchange routing information between PE routers and CE routers. A Layer 3 VPN allows customers to use different routing protocols and AS numbers at their sites, as long as they can peer with BGP at the PE-CE interface. In this example, CE-1 is using AS 65530 and CE-2 is using AS 65531, but they can still communicate through the VPN because they have BGP sessions with PE-1 and PE-2, respectively.
NEW QUESTION # 42
When building an interprovider VPN, you notice on the PE router that you have hidden routes which are received from your BGP peer with family inet labeled-unica3t configured.
Which parameter must you configure to solve this problem?
- A. Under the family inet labeled-unicast hierarchy, add the resolve-vpn parameter.
- B. Under the protocols ospf hierarchy, add the traffic-engineering parameter.
- C. Under the protocols mpls hierarchy, add the traffic-engineering parameter
- D. Under the family inet labeled-unicast hierarchy, add the explicit null parameter.
Answer: A
Explanation:
Explanation
The resolve-vpn parameter is a BGP option that allows a router to resolve labeled VPN-IPv4 routes using unlabeled IPv4 routes received from another BGP peer with family inet labeled-unicast configured. This option enables interprovider VPNs without requiring MPLS labels between ASBRs or using VRF tables on ASBRs. In this scenario, you need to configure the resolve-vpn parameter under [edit protocols bgp group external family inet labeled-unicast] hierarchy level on both ASBRs.
NEW QUESTION # 43
Exhibit
Referring to the exhibit, what do the brackets [ ] in the AS path identify?
- A. They identify an AS set, which are groups of AS numbers in which the order does not matter
- B. They identify that a BGP confederation is being used to ensure that there are no routing loops.
- C. They identify that the autonomous system number is incomplete and awaiting more information from the BGP protocol.
- D. They identify the local AS number associated with the AS path if configured on the router, or if AS path prepending is configured
Answer: A
Explanation:
Explanation
The brackets [ ] in the AS path identify an AS set, which are groups of AS numbers in which the order does not matter. An AS set is used when BGP aggregates routes from different ASs into a single prefix. For example, if BGP aggregates routes 10.0.0.0/16 and 10.1.0.0/16 from AS 100 and AS 200, respectively, into a single prefix 10.0.0.0/15, then the AS path for this prefix will be [100 200]. An AS set reduces the length of the AS path and prevents routing loops.
NEW QUESTION # 44
A packet is received on an interface configured with transmission scheduling. One of the configured queues In this scenario, which two actions will be taken by default on a Junos device? (Choose two.)
- A. The excess traffic will use bandwidth available from other queueses
- B. The exceeding queue will be considered to have negative bandwidth credit.
- C. The exceeding queue will be considered to have positive bandwidth credit
- D. The excess traffic will be discarded
Answer: B,D
Explanation:
Explanation
Transmission scheduling is a CoS feature that allows you to allocate bandwidth among different queues on an interface. Each queue has a configured bandwidth percentage that determines how much of the available bandwidth it can use. If a queue exceeds its allocated bandwidth, it is considered to have negative bandwidth credit and its excess traffic will be discarded by default. If a queue does not use all of its allocated bandwidth, it is considered to have positive bandwidth credit and its unused bandwidth can be shared by other queues.
NEW QUESTION # 45
Exhibit
Referring to the exhibit, CE-1 is providing NAT services for the hosts at Site 1 and you must provide Internet access for those hosts Which two statements are correct in this scenario? (Choose two.)
- A. You must configure a RIB group on PE-1 to leak a default route from the inet.0 table to the VPN-A.inet.0 table.
- B. You must configure a static route in the main routing instance for the 203.0.113.1/32 prefix that uses the VPN-A.inet.0 table as the next hop.
- C. You must configure a RIB group on PE-1 to leak the 10 1 2.0/24 prefix from the VPN-A.inet.0 table to the inet.0 table.
- D. You must configure a static route in the main routing instance for the 10 1 2.0/24 prefix that uses the VPN-A.inet.0 table as the next hop
Answer: B,D
Explanation:
Explanation
To provide Internet access for the hosts at Site 1, you need to configure static routes in the main routing instance on PE-1 that point to the VPN-A.inet.0 table as the next hop. This allows PE-1 to forward traffic from the Internet to CE-1 using MPLS labels and vice versa. You need to configure two static routes: one for the
10.1.2.0/24 prefix that represents the private network of Site 1, and one for the 203.0.113.1/32 prefix that represents the public IP address of CE-1.
NEW QUESTION # 46
Which origin code is preferred by BGP?
- A. Internal
- B. External
- C. Null
- D. Incomplete
Answer: D
Explanation:
Explanation
BGP uses several attributes to select the best path for a destination prefix. One of these attributes is origin, which indicates how BGP learned about a route. The origin attribute can have one of three values: IGP, EGP, or Incomplete. IGP means that the route was originated by a network or aggregate statement within BGP or by redistribution from an IGP into BGP. EGP means that the route was learned from an external BGP peer (this value is obsolete since BGP version 4). Incomplete means that the route was learned by some other means, such as redistribution from a static route into BGP. BGP prefers routes with lower origin values, so Incomplete is preferred over EGP, which is preferred over IGP.
NEW QUESTION # 47
Exhibit
user@Rl show configuration interpolated-profile { interpolate {
fill-level [ 50 75 drop-probability [ > }
class-of-service drop-profiles
];
20 60 ];
Which two statements are correct about the class-of-service configuration shown in the exhibit? (Choose two.)
- A. The drop probability gradually increases from 20% to 60% as the queue level increases from 50% full to
75% full - B. To use this drop profile, you apply it directly to an interface.
- C. To use this drop profile, you reference it in a scheduler.
- D. The drop probability jumps immediately from 20% to 60% when the queue level reaches 75% full.
Answer: A,C
Explanation:
Explanation
class-of-service (CoS) is a feature that allows you to prioritize and manage network traffic based on various criteria, such as application type, user group, or packet loss priority. CoS uses different components to classify, mark, queue, schedule, shape, and drop traffic according to the configured policies.
One of the components of CoS is drop profiles, which define how packets are dropped when a queue is congested. Drop profiles use random early detection (RED) algorithm to drop packets randomly before the queue is full, which helps to avoid global synchronization and improve network performance. Drop profiles can be discrete or interpolated. A discrete drop profile maps a specific fill level of a queue to a specific drop probability. An interpolated drop profile maps a range of fill levels of a queue to a range of drop probabilities and interpolates the values in between.
In the exhibit, we can see that the class-of-service configuration shows an interpolated drop profile with two fill levels (50 and 75) and two drop probabilities (20 and 60). Based on this configuration, we can infer the following statements:
* The drop probability jumps immediately from 20% to 60% when the queue level reaches 75% full. This is not correct because the drop profile is interpolated, not discrete. This means that the drop probability gradually increases from 20% to 60% as the queue level increases from 50% full to 75% full. The drop probability for any fill level between 50% and 75% can be calculated by using linear interpolation formula.
* The drop probability gradually increases from 20% to 60% as the queue level increases from 50% full to
75% full. This is correct because the drop profile is interpolated and uses linear interpolation formula to calculate the drop probability for any fill level between 50% and 75%. For example, if the fill level is
60%, the drop probability is 28%, which is calculated by using the formula: (60 - 50) / (75 - 50) * (60 -
20) + 20 = 28.
* To use this drop profile, you reference it in a scheduler. This is correct because a scheduler is a component of CoS that determines how packets are dequeued from different queues and transmitted on an interface. A scheduler can reference a drop profile by using the random-detect statement under the
[edit class-of-service schedulers] hierarchy level. For example: scheduler test { transmit-rate percent 10; buffer-size percent 10; random-detect test-profile; }
* To use this drop profile, you apply it directly to an interface. This is not correct because a drop profile cannot be applied directly to an interface. A drop profile can only be referenced by a scheduler, which can be applied to an interface by using the scheduler-map statement under the [edit class-of-service interfaces] hierarchy level. For example: interfaces ge-0/0/0 { unit 0 { scheduler-map test-map; } }
NEW QUESTION # 48
Your organization manages a Layer 3 VPN for multiple customers To support advanced route than one BGP community on advertised VPN routes to remote PE routers.
Which routing-instance configuration parameter would support this requirement?
- A. vrf-target export
- B. vrf-export
- C. vrf-target import
- D. vrf-import
Answer: A
Explanation:
Explanation
The vrf-target export parameter is used to specify one or more BGP extended community attributes that are attached to VPN routes when they are exported from a VRF routing instance to remote PE routers. This parameter allows you to control which VPN routes are accepted by remote PE routers based on their import policies. You can specify more than one vrf-target export value for a VRF routing instance to support advanced route filtering or route leaking scenarios.
NEW QUESTION # 49
You are asked to protect your company's customers from amplification attacks. In this scenario, what is Juniper's recommended protection method?
- A. unicast Reverse Path Forwarding
- B. BGP FlowSpec
- C. destination-based Remote Triggered Black Hole
- D. ASN prepending
Answer: C
Explanation:
Explanation
amplification attacks are a type of distributed denial-of-service (DDoS) attack that exploit the characteristics of certain protocols to amplify the traffic sent to a victim. For example, an attacker can send a small DNS query with a spoofed source IP address to a DNS server, which will reply with a much larger response to the victim. This way, the attacker can generate a large amount of traffic with minimal resources.
One of the methods to protect against amplification attacks is destination-based Remote Triggered Black Hole (RTBH) filtering. This technique allows a network operator to drop traffic destined to a specific IP address or prefix at the edge of the network, thus preventing it from reaching the victim and consuming bandwidth and resources. RTBH filtering can be implemented using BGP to propagate a special route with a next hop of
192.0.2.1 (a reserved address) to the edge routers. Any traffic matching this route will be discarded by the edge routers.
NEW QUESTION # 50
Exhibit
Referring to the exhibit, PE-1 and PE-2 are getting route updates for VPN-B when neither of them service that VPN Which two actions would optimize this process? (Choose two.)
- A. Configure the family route-target statement on the RR
- B. Configure the resolution rib bgp.l3vpn.O resolution-ribs inet. 0 Statement on the RR
- C. Configure the resolution rib bgp . 13vpn . 0 resolution-ribs inet. 0 Statement on the PEs.
- D. Configure the family route-target statement on the PEs.
Answer: A,B
Explanation:
Explanation
BGP route target filtering is a technique that reduces the number of routers that receive VPN routes and route updates, helping to limit the amount of overhead associated with running a VPN. BGP route target filtering is based on the exchange of the route-target address family, which contains information about the VPN membership of each PE device. Based on this information, a PE device can decide whether to accept or reject VPN routes from another PE device.
BGP route target filtering can be configured on PE devices or on route reflectors (RRs). Configuring BGP route target filtering on RRs is more efficient and scalable, as it reduces the number of BGP sessions and updates between PE devices. To configure BGP route target filtering on RRs, the following steps are required:
* Configure the family route-target statement under the BGP group or neighbor configuration on the RRs.
This enables the exchange of the route-target address family between the RRs and their clients (PE devices).
* Configure the resolution rib bgp.l3vpn.0 resolution-ribs inet.0 statement under the routing-options configuration on the RRs. This enables the RRs to resolve next hops for VPN routes using the inet.0 routing table.
* Configure an export policy for BGP route target filtering under the routing-options configuration on the RRs. This policy controls which route targets are advertised to each PE device based on their VPN membership.
NEW QUESTION # 51
Exhibit
Referring to the exhibit, you are receiving the 192.168 0 0/16 route on both R3 and R4 from your EBGP neighbor You must ensure that R1 and R2 receive both BGP routes from the route reflector In this scenario, which BGP feature should you configure to accomplish this behavior?
- A. multihop
- B. route-target
- C. multipath
- D. add-path
Answer: D
Explanation:
Explanation
BGP add-path is a feature that allows the advertisement of multiple paths through the same peering session for the same prefix without the new paths implicitly replacing any previous paths. This behavior promotes path diversity and reduces multi-exit discriminator (MED) oscillations. BGP add-path is implemented by adding a path identifier to each path in the NLRI. The path identifier can be considered as something similar to a route distinguisher in VPNs, except that a path ID can apply to any address family. Path IDs are unique to a peering session and are generated for each network3. In this question, we have a route reflector (RR) that receives two routes for the same prefix (192.168.0.0/16) from an EBGP neighbor. By default, the RR will only advertise its best path to its clients (R1 and R2). However, we want R1 and R2 to receive both routes from the RR. To achieve this, we need to configure BGP add-path on the RR and enable it to send multiple paths for the same prefix to its clients.
NEW QUESTION # 52
Which origin code is preferred by BGP?
- A. Internal
- B. External
- C. Null
- D. Incomplete
Answer: D
Explanation:
Explanation
BGP uses several attributes to select the best path for a destination prefix. One of these attributes is origin, which indicates how BGP learned about a route. The origin attribute can have one of three values: IGP, EGP, or Incomplete. IGP means that the route was originated by a network or aggregate statement within BGP or by redistribution from an IGP into BGP. EGP means that the route was learned from an external BGP peer (this value is obsolete since BGP version 4). Incomplete means that the route was learned by some other means, such as redistribution from a static route into BGP. BGP prefers routes with lower origin values, so Incomplete is preferred over EGP, which is preferred over IGP.
NEW QUESTION # 53
Exhibit
Referring to the exhibit, a working L3VPN exists that connects VPN-A sites CoS is configured correctly to match on the MPLS EXP bits of the LSP, but when traffic is sent from Site-1 to Site-2, PE-2 is not classifying the traffic correctly What should you do to solve the problem?
- A. Set a static CoS value for the PE-1_to_PE-2 LSP
- B. Configure VPN prefix mapping for the PE-1_to_PE-2 LSP
- C. Configure the explicit-null statement on PE-2
- D. Configure the explicit-null statement on PE-1.
Answer: D
Explanation:
Explanation
The explicit-null statement enables the PE router to send an MPLS label with a value of 0 (explicit null) instead of an IP header for packets destined to the VPN customer sites. This allows the penultimate hop router (the router before the egress PE router) to preserve the EXP bits of the MPLS label and pass them to the egress PE router. The egress PE router can then use these EXP bits to classify the traffic according to the CoS policy2
. In this example, PE-1 should configure the explicit-null statement under [edit protocols mpls label-switched-path PE-1_to_PE-2] hierarchy level.
NEW QUESTION # 54
......
JNCIP-SP Fundamentals-JN0-664 Exam-Practice-Dumps: https://www.realvalidexam.com/JN0-664-real-exam-dumps.html
Use Real JN0-664 Dumps - Juniper Correct Answers: https://drive.google.com/open?id=1dhTF-SHQOU2giYvMh1EdhO5IWHQvCiae
