A systems administrator is tasked with improving the fault tolerance for a mission-critical application server. The requirements are to prevent downtime from common component failures, such as power supplies and network cards, while also ensuring service continuity if the entire server chassis fails. Which of the following solutions BEST addresses all of these requirements?
Deploy an active-passive failover cluster using two servers, with each server having redundant power supplies and teamed network cards.
Upgrade the existing single server with hot-swappable dual power supplies and a four-port NIC configured for link aggregation.
Implement a hardware load balancer to distribute requests between two new, identically configured application servers.
Configure the server's storage with a RAID 1 array and schedule asynchronous replication to a cold standby server in another rack.
The correct solution is to deploy an active-passive failover cluster where each server also has redundant components. This layered approach addresses both requirements for fault tolerance. The active-passive cluster provides server-level redundancy, allowing the passive node to take over if the entire active server fails. Each server having dual power supplies and teamed network cards provides component-level redundancy, protecting against failures of those specific parts without causing a server-level failover.
Upgrading the single server with redundant components only addresses component-level failure and does not protect against a total server failure. Implementing a load balancer with two servers creates server-level redundancy but does not explicitly guarantee the required component-level redundancy is also in place. Configuring RAID and asynchronous replication is a data protection and disaster recovery strategy, not a high-availability solution designed to prevent service interruption from hardware failure.