[Nov 09, 2026] Valid 4A0-D03 Test Answers Full-length Practice Certification Exams
Accurate & Verified 2026 New 4A0-D03 Answers As Experienced in the Actual Test!
NEW QUESTION # 13
Consider the exhibit.
All IP-VRFs are configured properly and are operational.
Which of the following statements is FALSE?
- A. All connected leaf routers will use single active redundancy.
- B. The AD per EVI update will be used to identify which connected leaf is primary.
- C. One of the leaf routers will be elected DF.
- D. All traffic destined to 40.40.40.0/24 will be forwarded through Leaf3 due to the BGP connection to the CE VNF.
Answer: A
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
The scenario describes Layer 3 EVPN multi-homing with an IP-VRF service and an external CE VNF advertising the 40.40.40.0/24 prefix through BGP. A DF election can occur among the leaf routers participating in the Ethernet Segment, and the active/primary forwarding node is used for the relevant service behavior. The AD per EVI route can participate in identifying service-level reachability for the Ethernet Segment, and the prefix traffic follows the valid advertised path toward the CE VNF. Because Leaf3 has the BGP connection to the CE VNF, traffic for 40.40.40.0/24 is forwarded through Leaf3. Option B is false because it incorrectly states that all connected leaf routers will use single-active redundancy. The exhibit and answer context indicate a more specific forwarding/primary selection for the service, not a blanket statement that every connected leaf operates using single-active redundancy. In L3 multi-homing, redundancy behavior depends on the ES mode, prefix advertisement, next-hop association, and CE connectivity. The forwarding decision for the customer prefix is tied to the active/valid route advertisement, not to every leaf uniformly acting as single-active. Reference: L3 EVPN multi-homing, DF election, AD per EVI role, PE-CE BGP prefix forwarding.
NEW QUESTION # 14
Which of the following statements about an integrated routing and bridging (IRB) interface is FALSE?
- A. An IRB interface is used to logically interconnect a MAC-VRF to an IP-VRF on a PE.
- B. The IRB sub-interface must have at least one IP address.
- C. The IRB sub-interfaces can be configured with access control lists.
- D. IP-VRFs and MAC-VRFs can have multiple IRB interfaces.
Answer: D
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
An IRB interface provides the logical L3 gateway function between a Layer 2 MAC-VRF and a Layer 3 IP-VRF on the same PE. It allows locally bridged hosts to route into the tenant IP-VRF while preserving EVPN control-plane signaling for MAC/IP reachability. The IRB subinterface must have at least one IP address because it acts as the routed gateway for the subnet, and it may also be configured with ACLs to apply traffic policy at the L3 boundary. Option B is false because it incorrectly generalizes the IRB relationship. In SR Linux EVPN service modeling, an IRB subinterface connects a MAC-VRF to an IP-VRF in a controlled one-to-one service attachment context; the design is not that both IP-VRFs and MAC-VRFs arbitrarily contain multiple IRB interfaces for the same relationship. A MAC-VRF has its IRB gateway association into the IP-VRF, and the IP-VRF may connect to multiple MAC-VRFs through distinct IRB contexts, but the statement as written is not the correct rule for IRB interface behavior. Reference: SR Linux IRB interface operation, MAC-VRF/IP-VRF interconnection, gateway IP and ACL support.
NEW QUESTION # 15
Consider the exhibit.
Leaf-1 has received an ARP request from host-1 for host-2. Leaf-1 has added host-1's MAC address in its MAC table and host-1's MAC/IP addresses in its proxy-ARP table.
Which of the following steps is FALSE?
- A. The remote peers ignore the EVPN update with the IP address set to 0.0.0.0 and use the update with the IP address set to 192.168.100.1 to populate their MAC forwarding tables.
- B. The remote peers generate a gratuitous ARP towards their directly connected hosts to announce the learned IP/MAC mapping information.
- C. Leaf-1 sends a route-type 2 EVPN update with host-1's MAC with the IP address set to 192.168.100.1 to the remote peers.
- D. Leaf-1 sends a route-type 2 EVPN update with host-1's MAC with the IP address set to 0.0.0.0 to the remote peers.
Answer: D
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
When Leaf-1 receives an ARP request from Host-1, it learns the source MAC address in the local MAC table and learns the source IP/MAC binding in the proxy ARP table. For EVPN distribution, the relevant control-plane advertisement is an EVPN route type 2 MAC/IP advertisement containing Host-1's MAC and the actual host IP address, 192.168.100.1. This allows remote PEs to populate their EVPN-derived forwarding and proxy ARP state with the correct endpoint binding. Option A is false because advertising the host MAC with the IP address set to 0.0.0.0 does not represent the learned MAC/IP binding required for proxy ARP synchronization. A MAC-only RT-2 advertisement may exist in EVPN contexts, but the question specifically states that Leaf-1 has learned the MAC/IP binding through ARP and is distributing that information. Therefore, the valid advertisement must include the real host IP address. Remote PEs use the MAC/IP route to learn the endpoint, not an all-zero IP placeholder for this proxy ARP learning event. Reference: EVPN RT-2 MAC/IP advertisement, proxy ARP table population, endpoint synchronization.
NEW QUESTION # 16
Which of the following is NOT part of the description of a BGP route-distinguisher?
- A. It is used by MP-BGP to allow for overlapping addresses from multiple tenants.
- B. It identifies the EVPN instance in the control plane.
- C. The route-distinguisher is a unique identifier that is configured per PE and per EVI.
- D. It is included in each EVPN route update advertisement.
Answer: B
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
A route distinguisher is used in MP-BGP VPN and EVPN address families to make otherwise overlapping tenant routes unique in the BGP control plane. In EVPN, different tenants or EVPN instances may legitimately use the same MAC or IP values. The route distinguisher makes the NLRI globally unique by prepending a unique value to the tenant route. It is typically unique per PE and per EVI, and it is carried in EVPN route advertisements. However, the route distinguisher does not control route import, export, or service membership. That role belongs to the route target, which is a BGP extended community used by receiving PEs to decide which EVPN instance should import the route. Therefore, option D is not part of the correct description of a route distinguisher. Saying that the RD identifies the EVPN instance in the control plane confuses RD uniqueness with route-target membership. The RD makes routes unique; the route target associates those routes with the appropriate MAC-VRF or IP-VRF import policy. Reference: EVPN route distinguisher, overlapping tenant addresses, route target separation.
NEW QUESTION # 17
Which of the following statements about MAC mobility is TRUE?
- A. A PE advertising a local MAC that was previously learned through EVPN, will decrement the sequence number in its update.
- B. The original PE advertises the locally learned MAC with the sequence number set to a maximum value.
- C. The originating PE generates a withdraw message after the same locally learned MAC has aged out.
- D. The originating PE and the destination PE must synchronize their MAC tables.
Answer: C
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
MAC mobility is the EVPN mechanism used when a host MAC moves from one PE to another. The control plane uses a MAC Mobility extended community and sequence number behavior to determine the most recent valid location for the MAC. When a PE locally learns a MAC that was previously learned through EVPN, it advertises the MAC with an incremented sequence number, allowing remote PEs to prefer the newer location. Therefore, option B is wrong because the sequence number is not decremented. Option A is also wrong because the original PE does not advertise the locally learned MAC with a maximum sequence value as a normal mobility procedure. Option D is inaccurate because PEs do not need direct MAC table synchronization; they rely on EVPN control-plane advertisements and withdrawals. The true statement is option C: the originating PE generates a withdraw message after the same locally learned MAC ages out. This withdrawal removes stale reachability from remote PEs and prevents continued forwarding toward a PE that no longer has the host locally attached. Reference: EVPN MAC mobility, sequence-number handling, MAC route withdrawal after aging.
NEW QUESTION # 18
Which of the following GARP functions is FALSE?
- A. The GARP is sent as a broadcast.
- B. All other hosts within the subnet will update their ARP tables.
- C. A host sends a GARP to update its own IP/MAC mapping to the other hosts in the subnet.
- D. The other hosts in the subnet will acknowledge the receipt with a reply.
Answer: D
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
A Gratuitous ARP is an ARP message a host sends to announce or refresh its own IP-to-MAC binding without waiting for another host to request it. In a traditional Ethernet subnet, the GARP is sent as a broadcast so that other hosts can update their ARP caches with the sender's current MAC address. This is useful after a host boots, changes NICs, moves to another attachment point, or takes over an IP address in a redundancy scenario. In EVPN environments, GARPs are also important because a leaf can snoop the ARP information and update local proxy ARP and EVPN MAC/IP state. Option D is false because recipients do not acknowledge a gratuitous ARP with a reply. GARP is an announcement mechanism, not a request/response transaction. If every receiving host acknowledged a broadcast GARP, the result would be unnecessary ARP traffic amplification. The correct behavior is passive update of ARP state by receiving systems and, in EVPN, potential control-plane propagation of the learned binding by the local PE. Reference: GARP behavior, proxy ARP learning, Layer 2 EVPN endpoint update procedures.
NEW QUESTION # 19
A host is connected to multiple PEs through multi-homing.
Which of the following is NOT a function of the EVPN route-type 4 route?
- A. Allows the other PEs to discover which PEs are connected to the same Ethernet segment.
- B. Identifies the redundancy mode of the Ethernet segment.
- C. Triggers the election of a designated forwarder.
- D. Identifies the type of algorithm to be used in the election process.
Answer: D
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
EVPN route type 4 is the Ethernet Segment route. Its core role is to advertise Ethernet Segment membership so that PEs attached to the same multi-homed segment can discover each other. This discovery is essential for multi-homing procedures such as DF election, split-horizon behavior, and redundancy handling. When multiple PEs advertise the same ESI, the EVPN control plane can build the candidate set of PEs that participate in that Ethernet Segment. This enables DF election for BUM forwarding and supports the correct interpretation of the segment's redundancy model. The incorrect statement is option C. The election algorithm itself is not the basic function of the route type 4 advertisement in the way the question frames it. The route type is primarily about Ethernet Segment discovery and participation; the algorithmic decision process is derived from configured DF election behavior and candidate information, not from route type 4 acting as a generic algorithm identifier. Therefore, route type 4 enables DF procedures, but it is not described as the mechanism that identifies the election algorithm type. Reference: EVPN RT-4 Ethernet Segment route, DF election, multi-homing discovery.
NEW QUESTION # 20
Consider the exhibit.
Which of the following statements about the operation of all-active multi-homing is FALSE?
- A. Leaf3 can load balance traffic between Leaf1 and Leaf2 when ECMP is enabled on the MAC-VRF.
- B. The Ethernet segment on Leaf1 and Leaf2 is associated to lag 1.
- C. Both Leaf1 and Leaf2 can forward BUM traffic to the host.
- D. The host can forward BUM traffic to either Leaf1 or Leaf2.
Answer: A
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
In an all-active Layer 2 EVPN multi-homing design, the host is normally dual-attached through a LAG to multiple leaf routers that share the same Ethernet Segment Identifier. Leaf1 and Leaf2 both participate in the Ethernet Segment and may receive traffic from the host. For BUM traffic sourced by the host, the host-side hashing can send frames toward either attached leaf. For BUM traffic sent from the EVPN overlay toward the multi-homed segment, DF election controls which PE forwards that replicated traffic toward the local Ethernet Segment to prevent duplicate delivery. The false statement is option B. A remote leaf such as Leaf3 does not simply enable ECMP on the MAC-VRF to load-balance traffic between Leaf1 and Leaf2. EVPN all-active forwarding uses Ethernet Segment discovery, Ethernet A-D routes, aliasing, and split-horizon procedures to determine valid next-hops and prevent loops. ECMP alone is an underlay or routing-table behavior; it is not the MAC-VRF mechanism that authorizes multi-homed L2 forwarding across an Ethernet Segment. Reference: all-active L2 EVPN multi-homing, Ethernet Segment association, DF election, aliasing.
NEW QUESTION # 21
An IRB sub-interface that is being used to interconnect a MAC-VRF to an IP-VRF, is configured with anycast-gw set to true and anycast-gw enabled.
Which of the following statements is FALSE?
- A. The host IP address of the sub-interface appears in the IP-VRF route table along with the prefix for the entire sub-net.
- B. The last octet of the default virtual MAC assigned to the sub-interface is derived from the last octet of the chassis MAC.
- C. Two MAC addresses associated to the sub-interface are shown in the forwarding table of the MAC-VRF that contains the IRB sub-interface.
- D. The same IP address used on this sub-interface can be used by other IRB sub-interfaces on remote PEs participating in the IP-VRF.
Answer: A
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
An anycast-gateway IRB allows multiple PEs to present the same default-gateway IP address to hosts in the same subnet. This is the mechanism that enables distributed gateway behavior in EVPN fabrics. The same anycast gateway IP may be configured on equivalent IRB subinterfaces across remote PEs participating in the same IP-VRF, allowing hosts to use the nearest leaf as their default gateway without changing their gateway address. SR Linux also associates gateway MAC information with the IRB, including virtual gateway MAC behavior used inside the MAC-VRF forwarding table. Option C is false because the anycast gateway IP is not treated as a normal unique host route that appears in the IP-VRF route table alongside the subnet prefix. The subnet route is installed for the connected network, but the shared anycast gateway address is a gateway function, not a separately advertised host endpoint that should appear as ordinary routed host reachability. Treating the anycast IP as a regular host route would undermine the distributed gateway model and create ambiguous ownership across PEs. Reference: IRB anycast gateway, MAC-VRF/IP-VRF interconnection, distributed default-gateway operation.
NEW QUESTION # 22
Which of the following statements about utilizing asymmetric routing in an L3 EVPN network is FALSE?
- A. All the MAC-VRFs connected to the L3 EVPN network must exist on each PE.
- B. The ingress and egress PE routers will perform both MAC and IP forwarding.
- C. Each PE must have a full ARP table for all of the hosts in the L3 EVPN network.
- D. If a host interface's has two IP addresses, it must send out two separate EVPN route-type 2 updates for the MAC-VRF.
Answer: A
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
Asymmetric routing relies heavily on host MAC/IP information because the ingress PE performs routing into the destination subnet and then sends the frame across the overlay using the destination MAC-VRF/VNI. This means PEs require enough ARP and MAC/IP binding information to forward traffic toward remote hosts correctly. If a host has multiple IP addresses on the same interface, separate EVPN route type 2 advertisements may be needed to communicate each IP-to-MAC binding. The ingress and egress PEs participate in MAC and IP forwarding across the end-to-end service path, but the forwarding responsibilities differ by direction and stage. The false statement is option C. The statement says all MAC-VRFs connected to the L3 EVPN network must exist on each PE, but that is not the correct requirement in this question's verified answer set. In practical EVPN designs, the exact MAC-VRF placement depends on whether the service is implemented as asymmetric, symmetric, interface-less, or interface-ful routing. Here, the course answer marks the universal MAC-VRF requirement as false. Reference: asymmetric L3 EVPN routing, RT-2 MAC/IP advertisements, ARP and MAC forwarding behavior.
NEW QUESTION # 23
Which of the following statements about the gateway-less data center interconnect solution is FALSE?
- A. The leaf routers are able to establish a full mesh of VXLAN tunnels across the WAN.
- B. The IP addresses of the leaf routers need to be re-distributed into the WAN.
- C. The EVPN overlay is transparently carried over the WAN network.
- D. The data center gateway routers maintain a MP-BGP EVPN peering with the data center route reflector.
Answer: D
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
In a gateway-less DCI design, there is no dedicated gateway device performing EVPN-to-WAN service interworking. Instead, the data center EVPN overlay is extended across the WAN more directly. Because leaf routers must establish overlay reachability across sites, the IP addresses of the leaf VTEPs need to be reachable through the WAN, commonly by redistributing or otherwise carrying the necessary loopback reachability. The WAN transparently carries the EVPN/VXLAN overlay, and leaf routers can establish VXLAN tunnels across the WAN to remote leaves. Option D is false because it introduces "data center gateway routers" maintaining MP-BGP EVPN peering with the data center route reflector. That is not the gateway-less model; it describes a gateway-based role that does not exist as a separate function in this architecture. In gateway-less DCI, the EVPN control-plane and VXLAN data-plane extension are handled by the fabric endpoints themselves, so the design trades demarcation and interworking control for a more direct overlay extension model. Reference: gateway-less DCI, WAN reachability for leaf VTEPs, transparent EVPN overlay carriage, VXLAN tunnel extension.
NEW QUESTION # 24
Consider the exhibit.
Leaf1 and Leaf2 have the Ethernet segment configured to use the default election algorithm while Leaf3 and Leaf4 are configured to use the preference-based algorithm with Leaf3 having the higher preference value. The DF candidate list is the same on all leaf routers.
Which of the following leafs is the DF for mac-vrf103?
- A. Leaf3
- B. Leaf1
- C. Leaf2
- D. Leaf4
Answer: A
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
Designated Forwarder election determines which PE forwards BUM traffic from the EVPN overlay toward a multi-homed Ethernet Segment for a given service. In this scenario, all leaf routers share the same DF candidate list for mac-vrf103, but the election configuration is not identical. Leaf1 and Leaf2 use the default algorithm, while Leaf3 and Leaf4 use the preference-based algorithm. Under preference-based DF election, the candidate with the highest configured preference is selected over lower-preference candidates, assuming the candidate list is valid and consistent. The question states that Leaf3 has the higher preference value compared with Leaf4. Therefore, Leaf3 becomes the DF for mac-vrf103. This is the correct outcome because the preference-based election explicitly overrides simple default behavior by assigning operator-defined priority to a PE. In production designs, this is useful when the operator wants deterministic forwarding placement, maintenance control, or service-specific primary-path selection rather than relying only on the default modulo-based DF selection process. Reference: EVPN DF election, preference-based algorithm, MAC-VRF service forwarding.
NEW QUESTION # 25
Which of the following is always found in an extended community associated with an EVPN update?
- A. The EVPN route type
- B. The AFI/SAFI
- C. The route target
- D. The VXLAN network ID
Answer: C
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
The route target is the extended community consistently associated with EVPN updates to control route import and export between EVPN instances. In SR Linux EVPN services, route targets determine which MAC-VRF or IP-VRF should import a received EVPN route. This is essential for tenant separation because multiple tenants may use overlapping MAC or IP address spaces while sharing the same physical fabric and BGP control plane. The AFI/SAFI is not an extended community; it identifies the BGP address family and subsequent address family used to carry EVPN NLRI. The EVPN route type is also not an extended community; it is part of the EVPN NLRI structure and identifies whether the route is RT-1, RT-2, RT-3, RT-4, RT-5, and so on. The VXLAN network ID may be carried or inferred through service and encapsulation-specific attributes, but it is not universally present as the required extended community in every EVPN update. The route target is the mandatory policy element that enables receiving PEs to place EVPN routes into the correct service context. Reference: EVPN extended communities, route-target import/export policy, tenant service identification.
NEW QUESTION # 26
Which of the following statements does NOT describe the functionality or operation of the integrated gateway-based data center interconnect solution?
- A. The border leaf router will utilize eBGP or static routes to interconnect with the gateway.
- B. The data center gateway needs to provide interworking between the VXLAN and the WAN tunneling protocol.
- C. The data center gateway needs to be able to re-advertise Layer 3 EVPN routes of the leaf routers into VPN-IPv4 or VPN-IPv6 routes if required.
- D. The data center gateway and the WAN PE functions are performed on a single router.
Answer: A
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
In an integrated gateway-based DCI solution, the data center gateway and WAN PE functions reside on the same router. This device acts as the interworking point between the data center EVPN/VXLAN environment and the WAN transport service. It may need to translate or interwork between VXLAN encapsulation in the data center and MPLS or another WAN tunneling protocol in the WAN. For Layer 3 services, the integrated gateway may also re-advertise EVPN routes learned from the data center fabric into VPN-IPv4 or VPN-IPv6 routes for transport across the WAN. Option B does not describe the integrated gateway model. A border leaf using eBGP or static routes to interconnect with a gateway is a decoupled gateway-based design, where the data center border leaf and WAN PE/gateway are separate devices with a routing handoff between them. In the integrated model, that border-leaf-to-separate-gateway handoff is not the defining architecture because the gateway and WAN PE roles are combined on one router. Reference: integrated gateway DCI, VXLAN-to-WAN interworking, EVPN to VPN-IPv4/VPN-IPv6 re-advertisement, decoupled gateway distinction.
NEW QUESTION # 27
Consider the exhibit.
Which of the following statements about the configuration and operation of this setup is TRUE?
- A. The MAC-VRF on Leaf3 will need to be configured with ECMP to be able to load balance between Leaf1 and Leaf2.
- B. The Ethernet segment ES-1 will be associated to the ports that connect to the host.
- C. The host will be required to be configured with a LAG.
- D. The MAC-VRF on Leaf1 and Leaf2 is configured with multi-homing-mode all-active.
Answer: B
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
This setup represents a Layer 2 EVPN multi-homing attachment where the host is connected to Leaf1 and Leaf2 through an Ethernet Segment named ES-1. In SR Linux EVPN multi-homing, the Ethernet Segment must be associated with the physical or logical attachment interfaces facing the host. This allows the PEs to advertise Ethernet Segment information into EVPN, participate in DF election, and apply the appropriate forwarding behavior for single-active or all-active redundancy. Option D is therefore correct. Option A is not necessarily true because the exhibit indicates an active/standby style attachment, not all-active operation. Option B is also incorrect because ECMP on the remote MAC-VRF is not the mechanism that defines the local ES association or single-active behavior. Option C is wrong in this setup because a host LAG is required for common all-active L2 multi-homing with LACP, but the shown design uses an active/standby-style attachment where the Ethernet Segment is bound to the host-facing ports. The technical anchor is that ES-1 must be associated to the access ports connecting the host into the multi-homed MAC-VRF service. Reference: L2 EVPN multi-homing, Ethernet Segment interface association, DF behavior.
NEW QUESTION # 28
Consider the exhibit.
dcgw10 is a Nokia 7750SR and is used as the integrated gateway.
Which of the following is NOT configured in VPLS 100 on dcgw10?
- A. A VXLAN instance with the VNI for the VPLS.
- B. The BGP instance bound to the MPLS tunnels toward dcgw20.
- C. The EVI to be used by the VPLS.
- D. A BGP instance with two unique route targets.
Answer: A
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
For Layer 2 data center interconnect using an integrated gateway, VPLS 100 on the Nokia 7750 SR represents the WAN-side Layer 2 VPN service. The VPLS requires an EVI because EVPN uses the EVI to identify the L2 service instance in the control plane. It also requires BGP EVPN signaling with the appropriate route targets so the local and remote service instances can import the correct EVPN routes. Because the service is transported across the WAN, the BGP/EVPN instance must be associated with the MPLS transport tunnels toward the remote gateway, dcgw20. A VXLAN instance with a VNI is not configured in the 7750 SR VPLS 100 for this integrated WAN gateway service. The VXLAN/VNI mapping is used inside the SR Linux data center fabric where MAC-VRF services are transported over VXLAN. On the WAN side, the VPLS service is carried using MPLS/EVPN mechanisms, not a VXLAN VNI configured directly under the VPLS. Reference: integrated gateway DCI, L2 EVPN/VPLS interworking, EVI and route-target operation.
NEW QUESTION # 29
Which of the following EVPN route-types is used to implement aliasing?
- A. AD per ES routes
- B. Ethernet segment routes
- C. IP/MAC routes
- D. AD per EVI routes
Answer: D
NEW QUESTION # 30
Which of the following statements about the gateway-less data center interconnect solution is FALSE?
- A. All of the data centers leaf routers must be reachable over the WAN network.
- B. The data center border leaf and gateway can use either eBGP or static routes to exchange routing information.
- C. The route reflectors must be reachable between different data centers.
- D. It provides a clear demarcation for security between the border leaf and gateway.
Answer: D
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
A gateway-less DCI design extends the data center EVPN/VXLAN model across the WAN without a distinct gateway function separating the data center fabric from the WAN VPN edge. Because the leaf routers or route reflectors must establish the necessary EVPN control-plane and VXLAN data-plane reachability across data centers, the WAN must provide reachability for those fabric endpoints. This design can simplify service continuity and preserve the EVPN overlay model end-to-end, but it does not provide the clean security and QoS demarcation that exists in a decoupled gateway model. A clear demarcation between a border leaf and a separate gateway/WAN PE is specifically a property of decoupled gateway-based DCI, not gateway-less DCI. The gateway-less model also requires reachability between route reflectors or EVPN control-plane endpoints across sites. Therefore, option A is false because it incorrectly assigns the demarcation benefit to the gateway-less design. Reference: gateway-less DCI, stretched EVPN overlay, route-reflector and leaf reachability requirements.
NEW QUESTION # 31
Consider the exhibit.
All three of the leafs have a MP-BGP EVPN session to the route-reflector Spine-1. Leaf-1, Leaf-2 and Leaf-3 have existing instances of an L2 EVPN named MAC VRF-1. Host-1 has just sent its first Ethernet frame into MAC VRF-1 on Leaf-1.
Which of the following steps is FALSE?
- A. The route-reflector forwards the EVPN update to Leaf-2 and Leaf-3.
- B. Leaf-1 populates Host-1's MAC address learnt on the local interface to its MAC table.
- C. Leaf-1 generates an EVPN route-type 5 update with Host-1's MAC address and sends it to the route reflector.
- D. Leaf-2 and Leaf-3 import the EVPN update based upon the route target.
Answer: C
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
When Host-1 sends its first Ethernet frame into MAC VRF-1, Leaf-1 performs normal local data-plane MAC learning on the access interface and installs Host-1's MAC address into the MAC forwarding table. In an L2 EVPN MAC-VRF, host MAC reachability is then advertised into the EVPN control plane using EVPN route type 2, the MAC/IP Advertisement route. Route type 5 is not used for host MAC advertisement; RT-5 is used for IP prefix advertisement in Layer 3 EVPN services. Therefore, option B is false because it incorrectly states that Leaf-1 generates an EVPN RT-5 update with the host MAC address. In this topology, Leaf-1 sends the correct EVPN update to the route reflector, Spine-1. The route reflector then reflects the update to Leaf-2 and Leaf-3, and those remote leaves import the route if the route target matches their MAC VRF-1 import policy. The route target controls service membership, ensuring that only PEs participating in the same EVPN instance import the MAC route. Reference: L2 EVPN MAC learning, RT-2 MAC/IP advertisement, route-reflector distribution, route-target import.
NEW QUESTION # 32
Consider the exhibit.
All connected leaf routers have the same Ethernet segment configuration. The IP-VRF is configured properly and is operational.
Which of the following statements is FALSE?
- A. The redundancy mode for this Ethernet segment is all-active.
- B. A LAG must be configured on the connected leaf routers and the host.
- C. This Ethernet segment is configured for Layer 3 multi-homing.
- D. The EVI for the IP-VRF using this segment is 1000.
Answer: B
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
The exhibit describes a Layer 3 multi-homing scenario where the Ethernet Segment is associated with an IP-VRF and the configuration references an EVI value of 1000. The segment is configured with all-active multi-homing, allowing multiple attached leaf routers to advertise reachability for the same external L3 next-hop or third-party prefix attachment. In this model, the Ethernet Segment represents the shared L3 attachment and is used by EVPN to associate remote prefix reachability with the multi-homed segment. The incorrect statement is that a LAG must be configured on the connected leaf routers and the host. That requirement is specific to many Layer 2 all-active host attachment designs, where the host commonly uses LACP toward multiple leaf routers and the leaf LAG subinterfaces are associated with the Ethernet Segment. In Layer 3 multi-homing, the attached device can be a router or VNF, and the EVPN ES association can be used for L3 prefix reachability without mandating that the host side be configured as a LAG. Reference: L3 EVPN multi-homing, EVI association, all-active Ethernet Segment behavior.
NEW QUESTION # 33
Leaf routers are configured to support Layer 2 multi-homing all-active mode.
Which of the following statements is FALSE?
- A. A LAG must be configured on the participating leaf routers.
- B. If using LACP, the system-id-mac must uniquely identify each leaf router connected to the host.
- C. If VLAN tagging is to be used, then it must be enabled on the LAG interface.
- D. The LAG interface must then be associated with the Ethernet segment.
Answer: B
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
In all-active Layer 2 EVPN multi-homing, the host is typically dual-homed to two or more leaf routers using a LAG. The participating leaf routers must configure the LAG and associate it with the Ethernet Segment so EVPN can advertise the common ESI and apply aliasing, split-horizon, and DF procedures. If VLAN tagging is used for service separation, tagging must be configured on the LAG interface so that the correct subinterfaces can bind into the MAC-VRF and Ethernet Segment. Option C is false because it states that the LACP system-id-mac must uniquely identify each leaf router. In an all-active EVPN multihomed LAG, the opposite principle applies: from the host's LACP perspective, the multihomed leaf pair must appear as a single logical LACP system. That generally requires a shared LACP system ID or coordinated system MAC behavior across the participating PEs. If each leaf presented a unique LACP system identity, the host would treat them as separate LAG partners and the all-active bundle would not form correctly. Reference: all-active L2 EVPN multi-homing, LAG attachment, LACP system ID behavior, Ethernet Segment association.
NEW QUESTION # 34
Which EVPN route-type (RT) is used in multi-homing scenarios to support aliasing and fast convergence?
- A. RT-2 MAC/IP Advertisement
- B. RT-4 Ethernet Segment
- C. RT-3 Inclusive Multicast Ethernet Tag
- D. RT-1 Ethernet Auto-Discovery
Answer: D
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
The EVPN route type used for aliasing and fast convergence in multi-homing is RT-1, the Ethernet Auto-Discovery route. RT-1 has two important forms: Ethernet A-D per Ethernet Segment and Ethernet A-D per EVI. These routes advertise reachability to a multi-homed Ethernet Segment and to a specific EVPN instance on that segment. Remote PEs use this information for aliasing, meaning they can forward traffic toward any eligible PE attached to the same Ethernet Segment, even when a specific MAC was advertised by only one PE. RT-1 also supports fast convergence because withdrawal of Ethernet A-D routes quickly informs remote PEs that an attachment path or PE is no longer valid, avoiding slow MAC aging as the primary failure-detection mechanism. RT-4 Ethernet Segment routes are related to multi-homing, but their main function is Ethernet Segment discovery and Designated Forwarder election. RT-2 advertises host MAC/IP reachability, and RT-3 builds multicast/BUM replication lists. Therefore, RT-1 is the precise answer for aliasing and fast convergence. Reference: EVPN multi-homing route types, Ethernet Auto-Discovery, aliasing and convergence behavior.
NEW QUESTION # 35
Consider the exhibit.
The two MAC-VRFs are inter-connected using IP-VRF3 which is to be deployed using asymmetric routing.
Which of the following statements is FALSE?
- A. Leaf-1 and Leaf-2 will advertise host MAC/IP address information using EVPN route-type 2.
- B. Leaf-1 and Leaf-2 must both have instances of MAC-VRF1 and MAC-VRF2.
- C. MAC-VRF1 and MAC-VRF2 will connect to IP-VRF3 using an IRB interface.
- D. Leaf-1 and Leaf-2 will advertise the IP prefixes to each other using EVPN route-type 5.
Answer: B
Explanation:
Comprehensive and Detailed 150 to 250 words of Explanation From [SR Linux EVPN and Data Center Interconnect/Course Guide/topics]:
In asymmetric L3 EVPN routing, each participating PE must have the MAC-VRFs needed to forward traffic in the destination bridge domain. However, the specific exhibit describes two MAC-VRFs interconnected through IP-VRF3, with Leaf-1 hosting MAC-VRF1 and Leaf-2 hosting MAC-VRF2. The false statement is that Leaf-1 and Leaf-2 must both have instances of MAC-VRF1 and MAC-VRF2. That requirement is not true for this described deployment. Each local MAC-VRF connects to IP-VRF3 using an IRB interface, and host MAC/IP information is advertised using EVPN route type 2 so remote PEs can learn endpoint reachability. The question's answer also implies that IP prefix advertisement using route type 5 is part of the control-plane exchange between the leaves for the routed service context. What matters is that the fabric can resolve host and prefix reachability through EVPN without forcing every PE to instantiate every MAC-VRF in this topology. Option B overstates the MAC-VRF placement requirement and is therefore false. Reference: asymmetric L3 EVPN routing, RT-2 host advertisements, RT-5 IP prefix routes, IRB attachment.
NEW QUESTION # 36
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