HA pair connectivity

• A. A single controller with dual power supplies; failover is manual.
• B. A three-node cluster with quorum required.
• C. Two controllers sharing the same storage; if one fails, partner takes over transparent to clients.
• D. A single node with manual failover required.

Answer: (C)

High availability pairs rely on two controllers that work together and share the same storage. The key is automatic failover: if one controller fails, the other takes over immediately, and clients stay connected without noticing. This is achieved because the surviving node assumes control of the I/O and typically the same virtual IP or path continues to be used by clients.

The option that describes two controllers sharing storage and, upon one failing, the partner taking over transparently to clients, is the best fit. It captures both the shared storage and automatic, seamless failover that defines an HA pair.

Other setups either rely on a single controller (even with dual power supplies) or require manual intervention for failover, or involve a multi-node cluster with quorum, which is a different architecture and not the same as a two-controller HA pair.