Huawei HCIP-Data Center Network V1.0 H12-893_V1.0 Exam Questions

Answer : B

In Huawei's CloudFabric computing scenario, VM service traffic involves virtualized environments with VXLAN overlays and traditional VLANs. Let's evaluate each statement:

A . Traffic inside a fabric is VXLAN encapsulated: This is true. Within a CloudFabric network, VXLAN encapsulation is used to transport traffic across the fabric, enabling overlay networking for VMs. TRUE.

B . Inter-VPC traffic must pass through the firewall: This is false. Inter-VPC (Virtual Private Cloud) traffic can be routed directly between VPCs using a gateway or router (e.g., with EVPN Type 5 routes) without necessarily passing through a firewall, depending on security policies. Firewalls are optional for inter-VPC traffic, not mandatory. FALSE.

C . Traffic between VAS devices and service leaf nodes is VLAN encapsulated: This is true. Value-Added Services (VAS) devices (e.g., load balancers) often connect to service leaf nodes using VLAN encapsulation, especially in traditional or hybrid deployments. TRUE.

D . Traffic between vSwitches on virtual servers and server leaf nodes is VLAN encapsulated: This is true. Traffic from virtual switches (vSwitches) on hypervisors to physical server leaf nodes typically uses VLAN encapsulation over the physical NICs, before VXLAN overlay if applicable. TRUE.

Thus, B is the false statement because inter-VPC traffic does not always require a firewall.

Answer : B

VXLAN (Virtual Extensible LAN) is a network overlay technology that encapsulates Layer 2 Ethernet frames within UDP packets to extend Layer 2 networks over Layer 3 infrastructure, widely used in Huawei's CloudFabric data center solutions. The encapsulation process, often referred to as 'MAC-in-UDP,' involves wrapping the original Ethernet frame (including MAC addresses) inside a UDP packet.

UDP Encapsulation: The VXLAN header follows the UDP header, and the destination UDP port number identifies VXLAN traffic. The Internet Assigned Numbers Authority (IANA) has officially assigned UDP port 4789 as the default destination port for VXLAN.

Options Analysis:

A . 4787: This is not a standard VXLAN port and is not recognized by IANA or Huawei documentation.

B . 4789: This is the correct and widely adopted destination port for VXLAN, as specified in RFC 7348 and implemented in Huawei's VXLAN configurations.

C . 4790: This port is not associated with VXLAN and is unused in this context.

D . 4788: This is not a standard VXLAN port; it may be confused with other protocols but is not correct for VXLAN.

Thus, the destination port number used during UDP encapsulation in VXLAN is B (4789), aligning with Huawei's VXLAN implementation standards.

Answer : A, D

Multi-Chassis Link Aggregation Group (M-LAG) is a high-availability technology on Huawei CloudEngine (CE) series switches, where two switches appear as a single logical device to downstream devices. The peer-link between the M-LAG peers synchronizes critical information to ensure seamless failover if one device fails. Let's evaluate the entries:

A . MAC Address Entries: MAC address tables map device MACs to ports. In M-LAG, synchronizing MAC entries ensures that both switches know the location of connected devices. If one switch fails, the surviving switch can forward Layer 2 traffic without relearning MAC addresses, preventing disruptions. Required.

B . Routing Entries: Routing entries (e.g., OSPF or BGP routes) are maintained at Layer 3 and typically synchronized via routing protocols, not M-LAG peer-link packets. M-LAG operates at Layer 2, and while Layer 3 can be overlaid (e.g., with VXLAN), routing table synchronization is not a standard M-LAG requirement. Not Required.

C . IGMP Entries: IGMP (Internet Group Management Protocol) entries track multicast group memberships. While useful for multicast traffic, they are not critical for basic unicast traffic forwarding in M-LAG failover scenarios. Huawei documentation indicates IGMP synchronization is optional and context-specific, not mandatory for general traffic continuity. Not Required.

D . ARP Entries: ARP (Address Resolution Protocol) entries map IP addresses to MAC addresses, crucial for Layer 2/Layer 3 communication. Synchronizing ARP entries ensures the surviving switch can resolve IP-to-MAC mappings post-failover, avoiding ARP flooding or traffic loss. Required.

Thus, A (MAC address entries) and D (ARP entries) are essential for M-LAG synchronization to maintain traffic forwarding during failover, per Huawei CE switch M-LAG design.

Answer : B

In a network overlay, VXLAN (Virtual Extensible LAN) tunnels extend Layer 2 networks over a Layer 3 underlay, commonly implemented in Huawei's data center solutions. The endpoints of a VXLAN tunnel are VXLAN Tunnel Endpoints (VTEPs), which encapsulate and decapsulate traffic.

VTEP Roles: VTEPs can be physical switches (e.g., Huawei CloudEngine series), virtual switches (e.g., Open vSwitch on a hypervisor), or routers with VXLAN support. The endpoints are defined by their IP addresses, not their physical nature.

Deployment Flexibility: In modern data centers, VXLAN tunnels often connect physical switches to virtualized environments where VTEPs reside on hypervisors or servers hosting VMs. For example, a VM's vNIC might connect to a virtual switch (VTEP) that tunnels to a physical switch VTEP. Thus, both endpoints are not always physical switches; one or both can be virtual.

The statement is FALSE (B) because both endpoints of a VXLAN tunnel are not necessarily physical switches; they can include virtual VTEPs in hypervisors or other devices.

Answer : D

Centralized gateway deployment using BGP EVPN in Huawei's data center networks (e.g., CloudFabric) involves a gateway handling Layer 3 routing for VXLAN overlays. Let's evaluate each statement:

A . When configuring a VTEP, you need to create a Layer 2 BD and bind a VNI to the Layer 2 BD: A Bridge Domain (BD) is a Layer 2 broadcast domain in VXLAN, and a Virtual Network Identifier (VNI) is bound to it to segment traffic. This is a standard step when configuring a VXLAN Tunnel Endpoint (VTEP) to map the overlay network. TRUE.

B . A VXLAN tunnel is identified by a pair of VTEP IP addresses and can be established if the local and remote VTEP IP addresses are reachable to each other at Layer 3: VXLAN tunnels are established between VTEPs using their IP addresses as endpoints. Layer 3 reachability (e.g., via underlay routing) is required for tunnel establishment. TRUE.

C . When BGP EVPN is used to dynamically establish a VXLAN tunnel, the local and remote VTEPs first establish a BGP EVPN peer relationship and then exchange BGP EVPN routes to transmit VNI and VTEP IP address information. A VXLAN tunnel is then dynamically established between them: In BGP EVPN, VTEPs establish a BGP peer relationship, exchange routes (e.g., Type 2 for MAC/IP or Type 3 for multicast), and share VNI and VTEP IP details, enabling dynamic tunnel setup. TRUE.

D . When configuring a VTEP, you need to create an EVPN Instance in the Layer 2 BD and configure an RD for the local EVPN instance. You do not need to configure an RT: An EVPN Instance (EVI) is created within a BD, and a Route Distinguisher (RD) is configured to make routes unique. However, Route Targets (RTs) are also required to control route import/export between EVPN peers, ensuring proper VNI and route distribution. Stating that RT configuration is not needed is incorrect, as RTs are essential for BGP EVPN operation. FALSE.

Thus, D is the false statement because RT configuration is necessary in centralized gateway deployment with BGP EVPN.

Answer : B

In Huawei's CloudFabric Solution, iMaster NCE-Fabric is the SDN controller responsible for managing physical devices and virtual switches (vSwitches). The method of data collection is critical for network monitoring.

SNMP Usage: Simple Network Management Protocol (SNMP) is a traditional method for collecting alarms and logs from network devices. However, Huawei's modern SDN controllers, including iMaster NCE-Fabric, primarily use telemetry (e.g., gRPC, NETCONF) for real-time data collection from physical devices and vSwitches. Telemetry provides higher efficiency and granularity compared to SNMP.

CloudFabric Approach: The solution leverages telemetry-based data collection, as documented in FabricInsight and iMaster NCE-Fabric guides, to gather alarms, logs, and performance metrics. SNMP may be supported as a legacy option but is not the primary method in this context.

The statement is FALSE (B) because iMaster NCE-Fabric predominantly uses telemetry, not SNMP, for collecting alarms and logs.

Answer : D

To identify the false statement, we evaluate each option based on standard M-LAG documentation, such as Huawei's and Arista's guidelines, which are commonly referenced in HCIP-Data Center Network training.

Option A: In loose mode, if Type 1 configurations of the two M-LAG member devices are inconsistent, the member interface on the M-LAG backup device is in Error-Down state and an alarm is generated, indicating that Type 1 configurations on the two devices are inconsistent.

Evaluation: This statement is true. In loose mode, inconsistencies in Type 1 (key) configurations are still critical, as they can affect M-LAG operation. According to Huawei M-LAG Configuration Guide, when Type 1 configurations are inconsistent in loose mode, the system may place the member interface on the backup device into an Error-Down state and generate an alarm to alert administrators. This ensures that critical issues are flagged, even in loose mode, to prevent loops or packet loss.

Conclusion: True.

Option B: If Type 1 configurations of the two M-LAG member devices are inconsistent, certain problems may occur, such as loops and long-period packet loss when the status is normal.

Evaluation: This statement is true. Type 1 configurations are essential for M-LAG operation, and inconsistencies can lead to severe network issues. For example, mismatched LACP settings or VLAN mappings can create loops or cause packet loss, as noted in Arista M-LAG Documentation. These problems can persist even when the system appears normal, making consistency checks critical for troubleshooting and O&M.

Conclusion: True.

Option C: If Type 2 configurations of the two M-LAG member devices are inconsistent, the M-LAG running status may be abnormal. Compared with Type 1 configuration problems, Type 2 configuration problems are more likely to be detected and have less impact on the network.

Evaluation: This statement is true. Type 2 (common) configurations, such as QoS or STP settings, are less critical but can still affect network performance. According to Huawei M-LAG Best Practices, Type 2 inconsistencies are often detected during consistency checks but have a lower impact on M-LAG operation compared to Type 1 issues. They are also more likely to be flagged during monitoring, as they are less severe and easier to resolve.

Conclusion: True.

Option D: If Type 2 configurations of the two M-LAG member devices are inconsistent, an alarm that indicates key and common configuration inconsistencies is generated.

Evaluation: This statement is false. While Type 2 (common) configuration inconsistencies are detected during consistency checks, they do not typically trigger alarms, especially alarms that specifically indicate both key and common configuration inconsistencies. According to Huawei M-LAG Configuration Guide and Arista M-LAG Documentation, Type 2 inconsistencies may be logged or reported in system logs but are not severe enough to generate critical alarms unless they significantly impact network operation. Alarms are more commonly associated with Type 1 (key) configuration inconsistencies, as they pose a higher risk to M-LAG functionality.

Conclusion: False.