After enabling ARP protection, many users lose network access because ARP protection relies on DHCP snooping to build IP-to-MAC binding tables. Without DHCP snooping enabled and correctly configured, ARP inspection cannot verify ARP packets, causing legitimate traffic to be dropped.
Enabling DHCP snooping allows ARP inspection to validate ARP requests and responses.
Other options like dynamic IP lockdown, IGMP snooping, or DHCP reservations are unrelated or secondary.
References:
ArubaOS-CX ARP Inspection and DHCP Snooping Configuration Guide
HPE Aruba Network Security Best Practices
Aruba Troubleshooting ARP Protection Issues

When receiving a '404 - Not Found' HTTP response while attempting to configure a VLAN via REST API, the most common cause is specifying an incorrect URI endpoint. The correct approach is to specify the exact resource path for VLAN configuration, which is /rest/v1/system/vlan. Without the correct URI, the API will return a 404 error indicating the resource is not found.
Sending a POST request to login is necessary but not related to 404 after login.
Syntax errors in payload lead to 400-series errors but usually not 404.
Enabling REST API read/write is important but would result in different errors.
References:
ArubaOS-CX REST API Developer Guide
HPE Aruba Networking REST API Documentation
Aruba CX Switch RESTful API Examples

IGMP (Internet Group Management Protocol) supports several message types: Join, Leave, Query, and Report messages to manage multicast group membership.
Join messages indicate a host wants to join a multicast group.
Leave messages indicate a host is leaving a multicast group.
Query messages are sent by routers to discover group members.
Report messages are sent by hosts to indicate membership.
Therefore, the full set of IGMP message types supported includes Join, Leave, Query, and Report.
Options with only Leave and Report or only Join and Query are incomplete.
References:
RFC 2236 (IGMPv2) and RFC 3376 (IGMPv3)
HPE Aruba CX Multicast Configuration and IGMP Snooping Guide
ArubaOS-CX Network Protocols Manual

Colorless ports allow network devices to move or replace endpoints without changing port-level configurations, typically by automatically assigning network policies dynamically to any port.
HPE Aruba's solution for colorless ports is the VNBT (Virtual Network Boundary Tagging) feature. VNBT allows dynamic segmentation of traffic, so ports can automatically take on the policies assigned to devices regardless of physical port location.
VRRP is a first-hop redundancy protocol and unrelated to port colorlessness.
VSF (Virtual Switching Framework) is for switch stacking.
VRF (Virtual Routing and Forwarding) is for traffic segmentation.
Thus, VNBT is the correct feature to meet colorless port requirements.
References:
Aruba Dynamic Segmentation and VNBT Whitepapers
ArubaOS-CX User Guide for Dynamic Segmentation
Aruba Tech Docs on Colorless Ports and VNBT