Could you please explain the operation principles of VRRP and Hot Backup on the AC Controller?

Dear Support,

1. I would like to understand how VRRP and Hot Backup operate. Do they separately manage APs between the Master and Slave, or are they stacked like VSU (Active-Active)?

2. If I set up HA on the AC Controller using VRRP or Hot Backup, in the event of a Master failure, will the Slave be able to manage APs like the Master? Also, does the Slave require the same license as the Master?

Thank you and best regard.

Hello,

Qustion 1:
VRRP is a network protocol designed to increase the availability of default gateways in IP networks. It allows multiple routers to form a single virtual router, ensuring that if the primary router fails, another router can take over seamlessly without affecting network traffic.
1. Virtual Router: A group of routers that act as a single default gateway for hosts on a network.
2. Master Router: The router that actively forwards packets for the virtual router.
3. Backup Routers: Routers that stand by to take over if the Master Router fails.
4. Priority: Each router in the VRRP group has a priority value (0-255), with 255 being the highest. The router with the highest priority becomes the Master Router.
5. VRRP Advertisement: Periodic messages sent by the Master Router to inform backup routers that it is still active.

Hot Backup is a general term that refers to a mechanism where a secondary system is kept ready and synchronized with the primary system to take over immediately in case of a failure. In the context of networking, it often refers to redundant configurations similar to VRRP but can be implemented in various ways depending on the specific technology or vendor.
1. Primary System: The active system that handles all operations.
2. Secondary System: The backup system that monitors the primary system and is ready to take over.
3. Synchronization: Data and state information are continuously or periodically synchronized between the primary and secondary systems.
4. Failover Detection: Mechanisms to detect when the primary system fails.
5. Seamless Transition: The ability to switch from the primary to the secondary system without interrupting services.

Summary
VRRP is a standardized protocol specifically designed for router redundancy, ensuring that a virtual router can continue to forward traffic even if the primary router fails.
Hot Backup is a broader concept that can be applied to various systems and technologies, ensuring that a secondary system is always ready to take over in case of a primary system failure.
Both mechanisms aim to provide high availability and minimize downtime, but VRRP is more specialized for router redundancy, while Hot Backup can be applied to a wider range of systems.

Quetsion 2:
1. In the event of a Master failure, the Slave will manage APs like the Master.

2. Slave also requires a license. The license is not shared


Best regards,
Micca

GTAC-Micca replied at 2024-11-14 13:25
Hello,

Qustion 1:

Dear Support,

For example, if the AC Master has an additional Active License for 32 APs, combined with its original 32 APs, totaling 64 APs, and then the Master goes down, the Slave will only manage 32 APs by default. Is my understanding correct? If so, does this mean I need to purchase an additional 32-AP license for the Slave to ensure it can handle the same number of APs as the Master when the Master goes down?

Thank you and Best Regard.

Victor replied at 2024-11-14 14:02
Dear Support,
For example, if the AC Master has an additional Active License for 32 APs, combined  ...

Hello,

Your example is very clear. As you understand, the slave device requires the same number of licenses as the master in order for it to properly manage APs.


Best regards,
Micca