# Scalability and high availability of IPS engines and Layer 2 Engines

Scalability and high availability guarantee that the system can adapt to growing needs, simplify planned maintenance, and protect against hardware failure. IPS engines and Layer 2 Engines can be flexibly scaled up to form clusters of up to 16 devices that work as a single virtual entity.

Clustering IPS engines improves performance and provides high availability for the traffic inspection service.

In Layer 2 Engine Clusters, only one Layer 2 Engine node is active at a time. The other Layer 2 Engine nodes remain in standby mode. If the active Layer 2 Engine node fails, one of the standby nodes automatically starts processing traffic.