ACSP - Aruba Certified Switching Professional Virtual Router Redundancy (VRRP) Questions and Answers — Questions and Answers
Question 1: An administrator is configuring VRRP on two ArubaOS-CX switches to provide gateway redundancy for a critical VLAN. Switch-A is configured with a priority of 110 and Switch-B is configured with the default priority. Preemption is enabled on both switches. Initially, Switch-A is the Master. If Switch-A fails and then later recovers, what will be its final VRRP state?
- Backup
- Master (Correct answer)
- Standby
- Init
Correct answer: Master
With preemption enabled, a VRRP router with a higher priority will always attempt to become the Master. Since Switch-A has a higher priority (110) than Switch-B (default 100), it will take over the Master role from Switch-B once it recovers and its VRRP process is fully initialized.
Question 2: What is the standard format of the virtual MAC address used by an IPv4 VRRP group?
- 00-00-5E-00-02-{VRID}
- 00-00-0C-07-AC-{VRID}
- 00-00-5E-00-01-{VRID} (Correct answer)
- It is inherited from the physical MAC address of the Master router.
Correct answer: 00-00-5E-00-01-{VRID}
The IETF standard for VRRPv2 and VRRPv3 for IPv4 defines the virtual MAC address as 00-00-5E-00-01-{VRID}, where the first part is the IANA-assigned OUI and the last octet is the Virtual Router Identifier (VRID).
Question 3: A network engineer is setting up VRRP between two core switches. To ensure that a failover only occurs if a specific upstream link goes down, not just the switch itself, which VRRP feature should be configured?
- Preemption
- Hold-down timer
- Authentication
- Object Tracking (Correct answer)
Correct answer: Object Tracking
VRRP object tracking allows the priority of a VRRP instance to be dynamically adjusted based on the state of another object, such as a line-protocol state of an interface. By tracking an upstream interface, a failover can be triggered if that specific link fails, causing the priority to decrease.
Question 4: Which of the following is a key difference between VRRPv2 and VRRPv3?
- VRRPv3 supports authentication, while VRRPv2 does not.
- VRRPv2 supports both IPv4 and IPv6, while VRRPv3 only supports IPv6.
- VRRPv3 supports both IPv4 and IPv6, while VRRPv2 only supports IPv4. (Correct answer)
- VRRPv3 uses a higher default priority value than VRRPv2.
Correct answer: VRRPv3 supports both IPv4 and IPv6, while VRRPv2 only supports IPv4.
The primary enhancement of VRRPv3 over VRRPv2 is the addition of support for IPv6 networks. VRRPv2 is limited to IPv4 only. Additionally, authentication was removed in VRRPv3.
Question 5: Two ArubaOS-CX switches are configured in a VRRP group with the same priority value and preemption disabled. Which switch will become the VRRP Master?
- The switch with the lower physical MAC address.
- The switch that boots up first and initializes its VRRP instance.
- The switch with the higher IP address configured on the VRRP interface. (Correct answer)
- The election is random and non-deterministic.
Correct answer: The switch with the higher IP address configured on the VRRP interface.
When VRRP priorities are identical, the switch with the highest IP address on the interface participating in the VRRP group is elected as the Master. This is the standard tie-breaking mechanism.
Question 6: An administrator configures VRRP on an ArubaOS-CX switch. What is the default priority value for a VRRP router?
- 255
- 100 (Correct answer)
- 150
- 1
Correct answer: 100
The default priority for a VRRP router is 100. A higher value indicates a higher priority for becoming the Master router. The priority can be configured to a value between 1 and 254. A priority of 255 is reserved for the router that owns the virtual IP address (IP address owner).
ACSP - Aruba Certified Switching Professional Virtual Router Redundancy (VRRP) Questions and Answers
An administrator is configuring VRRP on two ArubaOS-CX switches to provide gateway redundancy for a critical VLAN.
Switch-A is configured with a priority of 110 and Switch-B is configured with the default priority.
Preemption is enabled on both switches.
Initially, Switch-A is the Master.
If Switch-A fails and then later recovers, what will be its final VRRP state?