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NEW QUESTION # 22
A routing policy has been created to advertise OSPF routes in BGP. Which statement is correct in this scenario?
- A. Apply the policy as an export policy within BGP.
- B. Apply the policy as an import policy within BGP.
- C. Apply the policy as an import policy within OSPF.
- D. Apply the policy as an export policy within OSPF.
Answer: A
Explanation:
When advertisingOSPF routesintoBGP, the appropriaterouting policyshould be applied as anexport policy in BGP.
Step-by-Step Breakdown:
* OSPF to BGP Route Advertisement:Routes learned via OSPF (a dynamic IGP) need to be exported into BGP to be advertised to external BGP peers. In Junos OS, this is done usingexport policies.
* Export Policies in BGP:An export policy controls which routes are advertised out of a BGP session. In this scenario, the routing policy must be applied toBGP as an export policyto export the OSPF-learned routes to external BGP peers.
* Policy Configuration:Example configuration:
set policy-options policy-statement EXPORT_OSPF term 1 from protocol ospf set policy-options policy-statement EXPORT_OSPF term 1 then accept set protocols bgp group <group-name> export EXPORT_OSPF This policy ensures that only OSPF routes are exported into BGP.
Juniper Reference:
* Routing Policy: Export policies are used in BGP to control route advertisements to peers, including those learned via OSPF.
NEW QUESTION # 23
What protocol and port does BGP use for control plane communication?
- A. protocol TCP, port 159
- B. protocol UDP, port 179
- C. protocol UDP, port 159
- D. protocol TCP, port 179
Answer: D
NEW QUESTION # 24
Fill in the blank: In BGP, the ___________ attribute is used to influence the best path selection process.
- A. Community
- B. MED (Metric or Multi-Exit Discriminator)
- C. AS_PATH
- D. Local Preference
Answer: B
NEW QUESTION # 25
Which operation mode command will display the mapping between the VLAN ID and ports on a switch?
- A. show ethernet-switching table
- B. show route
- C. show interfaces terse
- D. show vlans
Answer: D
Explanation:
To display themapping between VLAN IDs and portson a Juniper switch, the show vlans command is used.
Step-by-Step Breakdown:
* VLAN Information:The show vlans command displays detailed information about VLAN configurations, including the VLAN ID, associated interfaces (ports), and VLAN membership.
* Command Example:
show vlans
* This command will provide an output listing each VLAN, its ID, and the interfacesassociated with the VLAN, enabling network engineers to quickly verify VLAN to port mappings.
Juniper Reference:
* VLAN Verification: Use the show vlans command to verify which VLANs are configured on the switch and the ports that are members of those VLANs.
NEW QUESTION # 26
Which of the following statements are correct about the Spine/Leaf architecture? (Choose two)
- A. Each Leaf switch is directly connected to every server in the data center.
- B. Spine switches can connect directly to the data center's external network.
- C. The Spine layer switches interconnect various Leaf switches.
- D. The architecture reduces the need for inter-switch link (ISL) redundancy.
Answer: B,C
NEW QUESTION # 27
In the context of Layer 2 switching, what does RSTP stand for?
- A. Routing Switch Transport Protocol
- B. Resilient Switching Transport Protocol
- C. Rapid Spanning Tree Protocol
- D. Redundant Switching Tree Protocol
Answer: C
NEW QUESTION # 28
Which two prefixes are contributing routes to a 10.20.0.0/18 aggregate route? (Choose two)
- A. 10.20.0.0/24
- B. 10.20.100.0/24
- C. 10.20.0.0/16
- D. 10.20.60.0/23
Answer: A,D
NEW QUESTION # 29
What happens if a frame with a known destination MAC address enters a switch?
- A. The MAC address is added to the bridge table.
- B. The ingress PFE performs a MAC address lookup and determines the egress PFE and port.
- C. The ingress PFE sends the header information to the RE.
- D. The egress PFE performs a MAC address lookup and determines the ingress PFE and port.
Answer: B
NEW QUESTION # 30
What is the behavior of the default export policy for OSPF?
- A. Redistribute all routes.
- B. Forward all routes.
- C. Accept all routes.
- D. Reject all routes.
Answer: D
Explanation:
In Junos, thedefault export policyforOSPFis toreject all routesfrom being exported.
Step-by-Step Breakdown:
* Default Export Policy:By default,OSPFin Junos does not export any routes to other routing protocols or neighbors. This is a safety mechanism to prevent unintended route advertisements.
* Custom Export Policies:
* If you need to export routes, you must create a customexport policythat explicitly defines which routes to advertise.
* Example: You can create an export policy to redistribute static or connected routes into OSPF.
Juniper Reference:
* OSPF Export Behavior: In Juniper devices, the default policy for OSPF is to reject route advertisements unless explicitly configured otherwise through custom policies.
NEW QUESTION # 31
Which statement is correct about aggregate routes?
- A. The default next hop is reject.
- B. The default next hop is readvertise.
- C. The default next hop is discard.
- D. The default next hop is resolve.
Answer: A
Explanation:
An aggregate route is a summarized route that is created by combining multiple specific routes into a single, broader route. In Junos OS, when an aggregate route is configured, its default next hop is set toreject.
Step-by-Step Explanation:
* Aggregate Route:Aggregate routes are used to reduce the size of routing tables by representing a collection of more specific routes with a single summary route. They help improve routing efficiency and scalability, especially in large networks.
* Default Next Hop Behavior:
* When you configure an aggregate route in Junos OS, it has arejectnext hop by default.
* Therejectnext hop means that if a packet matches the aggregate route but there is no more specific route in the routing table for that destination, the packet will be discarded, and an ICMP
"destination unreachable" message is sent to the source.
* This behavior helps to prevent routing loops and ensures that traffic isn't forwarded to destinations for which there is no valid route.
* Modifying Next Hop:If needed, the next hop behavior of an aggregate route can be changed todiscard (which silently drops the packet) or to another specific next hop. However, by default, the next hop is set toreject.
Juniper Reference:
* Junos Command: set routing-options aggregate route <route> reject to configure an aggregate route with a reject next hop.
* Verification: Use show route to verify the presence and behavior of aggregate routes.
NEW QUESTION # 32
Which two statements about IBGP are correct? (Choose two.)
- A. By default, IBGP has a TTL of 1.
- B. By default, IBGP has a TTL of 255.
- C. IBGP uses full mesh for loop prevention.
- D. IBGP uses AS path for loop prevention.
Answer: B,C
Explanation:
IBGP (Internal Border Gateway Protocol)is used to exchange routing information betweenrouters within the same AS (Autonomous System).
Step-by-Step Breakdown:
* TTL of 255:
* By default, IBGP sessions are established with aTTL (Time to Live)value of255. This allows IBGP neighbors to communicate over multiple hops within the AS without requiring any additional configuration.
* Full Mesh Requirement:
* IBGP requires alogical full meshbetween all IBGP routers to ensure that routing information is fully distributed within the AS. Since IBGP does not propagate routes learned from one IBGP peer to another by default, a full mesh topology is needed unlessroute reflectorsorBGP confederationsare used.
Juniper Reference:
* IBGP Full Mesh: Juniper recommends using route reflectors in large networks to simplify IBGP full- mesh requirements.
NEW QUESTION # 33
With regards to graceful restart, which two statements are true? (Choose two.)
- A. The network topology must be stable for graceful restart to work.
- B. A supported routing protocol, such as BGP, must be operational for graceful restart to work.
- C. Dual routing engines are required for graceful restart to work.
- D. NSR must be enabled for graceful restart to work.
Answer: A,B
NEW QUESTION # 34
Which of the following statements are true regarding Graceful Restart (GR)? (Choose two)
- A. It is used to increase the convergence time of the network.
- B. It helps in maintaining uninterrupted forwarding during a routing process restart.
- C. It decreases network stability during protocol restarts.
- D. It requires support from both the restarting router and its neighbors.
Answer: B,D
NEW QUESTION # 35
Referring to the exhibit, how many stages are in this IP fabric?
- A. 0
- B. 1
- C. 2
- D. 3
Answer: B
NEW QUESTION # 36
What does VXLAN stand for in the context of EVPN/VXLAN?
- A. Very Extended Virtual LAN
- B. Virtual X-Series LAN
- C. Virtualized Ethernet VPN
- D. Virtual Extensible VLAN
Answer: D
NEW QUESTION # 37
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