Free JN0-683: Data Center - Professional (JNCIP-DC) Exam Questions and Answers

Which statement describes an over-the-top (OTT) EVPN-VXLAN DCI?

• AA. Each data center uses a different VNI for the same VLAN, which the interconnect devices translate at the edge
• BB. VXLAN tunnels are established directly between leaf devices in different data centers across the IP transit network
• CC. Border leaf devices terminate the VXLAN tunnels from the local fabric and re-originate the EVPN routes toward the remote site
• DD. The provider PE routers participate in the EVPN control plane and map each VNI to an MPLS label-switched path

A company is moving virtual machines between two data centers that both use EVPN-VXLAN with an ERB architecture. Each VM must keep its IP address and default gateway during live migration. Which DCI approach meets the requirement?

• AA. Layer 3 stretch with a unique subnet in each data center and static routes to the remote border leaf
• BB. Layer 2 stretch of the VLAN with the same VNI at both sites, using EVPN Type 2 routes
• CC. Layer 2 stretch of the VLAN that uses EVPN Type 3 routes only and a separate gateway address per site
• DD. Layer 3 stretch that advertises each VM subnet from both data centers as EVPN Type 5 routes

Referring to the exhibit, hosts in VLAN 10 on leaf1 and leaf2 cannot communicate. On leaf1, the show route table bgp.evpn.0 command displays Type 2 routes from leaf2, but the MACVRF-A.evpn.0 table contains no remote MAC entries. What is the cause? Exhibit: user@leaf1> show configuration routing-instances MACVRF-A instance-type mac-vrf; protocols { evpn { encapsulation vxlan; extended-vni-list 5010; } } vtep-source-interface lo0.0; service-type vlan-based; interface xe-0/0/10.0; route-distinguisher 10.255.0.1:10; vrf-target target:65000:10; vlans { v10 { vlan-id 10; vxlan { vni 5010; } } } user@leaf2> show configuration routing-instances MACVRF-A instance-type mac-vrf; protocols { evpn { encapsulation vxlan; extended-vni-list 5010; } } vtep-source-interface lo0.0; service-type vlan-based; interface xe-0/0/10.0; route-distinguisher 10.255.0.2:10; vrf-target target:65000:20; vlans { v10 { vlan-id 10; vxlan { vni 5010; } } }

• AA. The extended-vni-list must be configured with a different VNI on each leaf device
• BB. The vtep-source-interface must be set to an IRB interface instead of lo0.0
• CC. The route distinguishers differ, and they must be identical on both leaf devices
• DD. The vrf-target values differ, so leaf1 does not import the routes that leaf2 exports

Which EVPN route type does a VTEP use to advertise its interest in a VNI so that remote VTEPs can build the BUM replication list?

• AA. Type 5 IP prefix advertisement route
• BB. Type 2 MAC/IP advertisement route
• CC. Type 3 inclusive multicast route
• DD. Type 1 Ethernet auto-discovery per-ESI route

You are designing a 3-stage Clos IP fabric. Each spine device has 36 ports, all of which connect to leaf devices. Each leaf device has one uplink to every one of the 4 spine devices. What is the maximum number of leaf devices the fabric supports?

• AA. 4
• BB. 9
• CC. 36
• DD. 144

Which UDP destination port is used by VXLAN-encapsulated frames?

• AA. 3784
• BB. 4789
• CC. 4791
• DD. 6081

Users report intermittent packet loss on traffic crossing a leaf-to-spine link. The SNMP system polls interface counters every 60 seconds and shows average utilization of 35 percent on that link, with no interface errors. You suspect short traffic bursts that exceed queue capacity. In this scenario, what should you do to confirm the cause?

• AA. Reduce the SNMP polling interval to 30 seconds and compare the new averages
• BB. Configure a Junos telemetry sensor for queue statistics with a one-second reporting rate
• CC. Enable sFlow on the link with a sampling rate of 1 in 2000 packets
• DD. Configure SNMP traps for linkDown and linkUp events on the interface

Leaf1 (VTEP address 10.1.255.1) forwards a frame from a local host to a host attached to leaf2 (VTEP address 10.1.255.2) over VNI 5010. Which two statements are correct about the VXLAN packet that leaf1 sends into the underlay? (Choose two.)

Select 2 answers.

• AA. The outer destination MAC address is the MAC address of the remote host.
• BB. The outer UDP destination port is 4789.
• CC. The outer destination IP address is 10.1.255.2.
• DD. The VNI is carried in a 12-bit field of the VXLAN header.

What is the size of the VXLAN Network Identifier (VNI) field in the VXLAN header?

• AA. 12 bits
• BB. 16 bits
• CC. 24 bits
• DD. 32 bits

Referring to the exhibit, leaf1 has an established IBGP session with the route reflector at 10.1.255.2, but leaf1 receives no EVPN routes. What is the cause? Exhibit: user@leaf1> show bgp neighbor 10.1.255.2 Peer: 10.1.255.2+179 AS 65000 Local: 10.1.255.11+60214 AS 65000 Group: overlay Routing-Instance: master Type: Internal State: Established Flags: <Sync> Last State: OpenConfirm Last Event: RecvKeepAlive Options: <Preference LocalAddress AddressFamily Rib-group Refresh> Address families configured: inet-unicast Local Address: 10.1.255.11 Holdtime: 90 Preference: 170 NLRI advertised by peer: inet-unicast evpn NLRI for this session: inet-unicast

• AA. The overlay BGP group does not have family evpn signaling configured on leaf1.
• BB. The overlay BGP group requires the multihop statement because the peers use loopback addresses.
• CC. The vtep-source-interface statement is missing from the protocols bgp hierarchy.
• DD. The default-switch routing instance does not have a vrf-target statement configured.