ACA Cheat Sheet 2026

The 30 highest-yield ACA facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What is a characteristic of a MAC address? → Assigned by the manufacturer
2. What is the recommended maximum retry count behavior when a wireless client fails to connect to an AP? → The client backs off using exponential backoff and retries up to a vendor-defined limit
3. Which Aruba feature steers dual-band capable clients to the 5 GHz band instead of 2.4 GHz? → Band Steering
4. What is the primary function of Aruba ClearPass in a wireless deployment? → It provides network access control, authentication, and policy enforcement
5. Aruba AirWave differs from Aruba Central in that AirWave is primarily: → An on-premises network management system supporting multi-vendor environments
6. What does the TTL (Time to Live) field in an IP packet header prevent? → Packets from looping indefinitely through a network
7. Which Aruba CLI command on the Mobility Controller displays the current firewall policy applied to a specific connected client? → show datapath user
8. Which STP port state actively forwards traffic in a classic 802.1D implementation? → Forwarding
9. In Aruba AirWave, what does the 'Rogue AP' detection feature identify? → Unauthorized access points not managed by the organization
10. What does LLDP (Link Layer Discovery Protocol) help you determine during troubleshooting? → Which devices are directly connected to each network port
11. A ClearPass administrator wants to allow guests to self-register. Which ClearPass module provides the guest self-registration portal? → ClearPass Guest
12. Which Aruba Central feature helps identify which clients are experiencing poor wireless connectivity? → Client Health
13. Which IEEE 802.11 amendment introduced OFDMA as a key feature to improve multi-user efficiency? → 802.11ax
14. Which 802.11 power management feature allows an AP to buffer frames for sleeping clients and notify them via TIM? → Legacy Power Save (PS-Poll)
15. What is the minimum recommended action when a ClearPass posture check determines that a connecting device has an outdated antivirus signature? → Assign a quarantine role that redirects to a remediation page
16. Which command on an Aruba CX switch shows the IP routing table? → show ip route
17. In Aruba's role-based access control, when is a firewall policy applied to a wireless client? → When the client is assigned a user role after authentication
18. Which Aruba AP mounting form factor is specifically designed for deployment behind TVs and in hotel rooms? → AP-303H
19. In a switched Ethernet network, what is the effect of placing two departments on separate VLANs? → It separates broadcast domains, limiting broadcasts to each VLAN
20. What is Aruba's Zero Touch Provisioning (ZTP) feature used for? → Automatically configuring new devices when they connect to the network
21. Which IPv6 address type is equivalent to the IPv4 private address range and is used only within a local network? → Link-Local
22. Which IEEE standard defines the Spanning Tree Protocol used to prevent loops in a switched network? → IEEE 802.1D
23. In WPA3-Enterprise, which security improvement over WPA2-Enterprise is mandatory? → 192-bit minimum security suite (CNSA)
24. Which Aruba product is purpose-built for location services and indoor wayfinding applications? → Aruba Meridian
25. Which Aruba security feature uses tunneled node to forward all client traffic to a central security inspection point? → Dynamic Segmentation with tunnel mode
26. What does the subnet mask /24 indicate about an IP network? → The first 24 bits are the network portion, leaving 8 bits for hosts (254 usable hosts)
27. Which protocol dynamically assigns IP addresses, subnet masks, gateways, and DNS server information to hosts? → DHCP
28. What does the Aruba GreenLake for Networking offering provide to customers? → A consumption-based, as-a-service model for Aruba networking infrastructure
29. What does 'flapping' mean in the context of network interfaces or routing protocol neighbors? → A port or neighbor repeatedly going up and down in rapid succession
30. On Aruba AOS-CX switches, where are QoS policies most commonly applied to enforce traffic prioritization? → On ingress and egress interfaces using QoS profiles