4A0-D01 Questions and Answers

Comprehensive and Detailed Explanation with Exact Extracts:

Option A (TRUE): Type 1 routes enable multi-homing functions.

Extract from Nokia EVPN Multi-Homing Guide:

"Type 1 Ethernet A-D routes signal reachability for an Ethernet Segment (ES) and enable fast convergence/aliasing in multi-homing."

Option B (TRUE): Type 4 routes facilitate DF election.

Extract from Nokia EVPN Fundamentals Guide:

"Type 4 Ethernet Segment routes advertise ESI and VTEP IP to peers for Designated Forwarder (DF) election, which prevents BUM traffic loops."

Option C (FALSE): The ESI is globally unique, not locally significant.

Extract from Nokia SR Linux Configuration Guide (Section: EVPN ESI):

"The ESI must be unique network-wide and consistently configured on all leafs attached to the same multi-homed device. It is not locally significant."

Option D (TRUE): An ES defines the host connectivity model.

Extract from Nokia EVPN Multi-Homing Guide:

"An Ethernet Segment (ES) is a set of links connecting a single host (e.g., server) to one or more leafs for redundancy/load balancing."

Comprehensive and Detailed Explanation with Exact Extracts:

Options A, B, and D are supported:

SR Linux users (A): Locally configured users for CLI/management access.

Regular Linux OS users (B): Native Linux users (e.g., admin) for host OS operations.

Remote users (D): Authenticated via AAA (TACACS+/RADIUS).

Extract from Nokia SR Linux System Management Guide:

"User types include SR Linux users (CLI access), Linux OS users (host system), and remote users (external AAA)."

Option C (Container users) is NOT supported:

SR Linux does not define "container users" as a distinct category. Containers (e.g., management container) share the host's user management.

Extract from Nokia SR Linux Security Guide:

"SR Linux does not provision separate user identities for containers. User access is managed at the host OS level or via SR Linux CLI, with no container-specific user type."

Comprehensive and Detailed Explanation:

Nokia’s Fabric Services System (FSS) employs an intent-driven approach where the fabric intent is defined in a YAML file. This file specifies the desired state of the data center fabric, including topology, services, and policies. FSS translates this declarative intent into device-specific configurations.

Exact Extract:

"Fabric Services System uses intent-based YAML templates to define the fabric’s target state. The system automates configuration generation and deployment, ensuring consistency across the fabric."

Comprehensive and Detailed Explanation with Exact Extracts:

Option A is FALSE: The provisioning script URL is not defined in the TLS profile. It is provided via DHCP (option 239) or DNS.

Extract from Nokia SR Linux ZTP Guide:

"The DHCP server supplies the URL to the provisioning script (via option 239). TLS profiles secure script/image downloads but do not define the script location."

Options B, C, and D are TRUE:

B: ZTP is managed by the ztp application in the management container.

C: DHCP provides initial IP/gateway.

D: ZTP requires no manual configuration.

Extract from Nokia SR Linux Installation Guide:

"The ZTP application automates deployment. It uses DHCP for network parameters and fetches scripts to make the device operational without pre-configuration."

Comprehensive and Detailed Explanation From Exact Extract:

Option A: TRUE – IP addresses are assigned to IRB subinterfaces.

"The IRB subinterface configuration includes the IP address for integrated routing."

— SR Linux EVPN Guide, "IRB Configuration"

Option B: TRUE – IRB subinterfaces reside in IP-VRF instances.

"IRB subinterfaces are associated with an IP-VRF network instance for L3 routing."

— SR Linux Network Instance Guide, "IP-VRF Setup"

Option C: FALSE – One IRB subinterface serves an entire MAC-VRF (L2 domain), not per interface.

"A single IRB subinterface provides L3 gateway services for all interfaces in a MAC-VRF instance."

— SR Linux EVPN Guide, "Asymmetric IRB Design"

Option D: TRUE – Each MAC-VRF uses one IRB subinterface.

"Each MAC-VRF network instance requires exactly one IRB subinterface for inter-subnet routing."

— SR Linux Network Instance Guide, "MAC-VRF Integration"