When storage failover (SFO) occurs and cluster mode SAN protocols are enabled on a data vserver:

When SFO occurs, the HA partner takes ownership of the failed node's aggregates and LUNs. ALUA reflects this ownership change by marking the partner's FC or iSCSI paths as 'active optimized' (direct path), because the partner now locally owns and serves those LUNs without requiring an inter-node cluster interconnect hop, enabling hosts to immediately route I/O over the most efficient available path.

An active indirect (non-optimized) ALUA path indicates I/O must traverse the cluster interconnect to a non-owning node; after SFO the HA partner directly owns the storage, so its paths are classified as direct (optimized), not indirect.

ALUA path classification is based on actual LUN ownership and does not arbitrarily promote paths to active optimized regardless of ownership - the optimized designation is only assigned to paths through the node that currently owns the LUN.

ALUA is a core mechanism for SAN non-disruptive operations and is actively involved in path state signaling during SFO, communicating path changes to the host so it can reroute I/O to the partner node's available paths.