H19-308_V4.0 Exam Dumps : HCSA-Presales-Storage V4.0

According to Huawei’s BCManager and HyperReplication guides, " incorrect " statements must be identified to understand the distinction between disaster recovery (DR) and active-active solutions. Option B is incorrect because while HyperMetro supports automatic transparent failover (zero RTO) using a Quorum Server, standard synchronous remote replication typically requires manual intervention or third-party management software to trigger a switchover when the primary site fails. In synchronous replication, the secondary LUN is usually in a read-only state and cannot take over automatically without administrative action.

Option D is incorrect because it describes an " Active-Active " state. In a standard Remote Replication pair, only the primary LUN is accessible for host I/O (Read/Write), while the secondary LUN is locked to maintain data consistency. Only the HyperMetro feature allows both LUNs in the pair to provide simultaneous read and write services to application servers across different sites. Regarding distance, while asynchronous replication is physically less constrained, synchronous and HyperMetro technologies are strictly limited by latency (typically requiring round-trip time < 10ms and distance within 100km to 300km depending on the specific product line) to avoid severe application performance degradation.

The Huawei OceanStor Dorado series is engineered for 99.9999% availability using multiple layers of reliability. Option A is correct as RAID-TP (Triple Parity) is a unique Huawei feature that uses three parity chunks to tolerate the simultaneous failure of any three SSDs in a disk group. Furthermore, the SmartMatrix full-mesh architecture in high-end models allows the system to remain operational even if seven out of eight controllers in a controller enclosure fail, ensuring extreme service continuity.

Option B is correct because Huawei utilizes Global Wear Leveling to distribute writes across all SSDs to extend their lifespan, and Anti-Wear Leveling to prevent multiple SSDs from reaching their end-of-life simultaneously, which avoids multi-disk failure risks. Option C is correct as the system supports HyperMetro (Active-Active) for both block (SAN) and file (NAS) services, providing zero RTO and RPO across sites. Option D is correct because Dorado supports high-reliability disk enclosure connection technologies; in a multi-enclosure setup, the system can tolerate the failure of an entire disk enclosure without data loss by using intelligent data distribution across different enclosures.

Huawei OceanStor Dorado supports Non-disruptive Upgrade (NDU), which allows the storage system’s software (firmware) to be upgraded while services are running. In a traditional storage environment, an upgrade might require a system reboot or cause a failover that interrupts I/O for several seconds or minutes. However, Dorado ' s NDU leverages the multi-controller architecture and advanced caching mechanisms.

During an NDU, the system upgrades controllers one by one or in batches. While one controller is being upgraded and rebooted, its workloads are transparently taken over by other active controllers in the same cluster. Because the host-side multipathing software handles the path failover and the storage system maintains cache mirroring, the application servers experience zero downtime and negligible performance impact. This feature is essential for mission-critical environments that require 24/7 availability and cannot afford scheduled maintenance windows for routine software updates.