Free Huawei H19-308_V4.0 Practice Exam with Questions & Answers

This statement is false because RAID 0 and Mirroring (RAID 1) are fundamentally different concepts in Huawei storage technology. As defined in the Huawei technical manual, RAID 0 is "Striping." It breaks data into chunks and spreads them across multiple disks to increase performance. It has no redundancy.

"Mirroring" is the terminology specifically used for RAID 1. In a RAID 1 configuration, the system writes the exact same data to two separate physical disks simultaneously. This creates a 100% redundant copy (a mirror). If one disk fails, the other continues to provide data, ensuring zero downtime and no data loss. Huawei'sRAID 2.0+ virtualization technologycan implement striping and mirroring across different "chunks" or "extents" within a storage pool, but it maintains the technical distinction: RAID 0 is for performance through striping, while mirroring is for reliability through duplication. Therefore, characterizing RAID 0 as a mirroring technology is a technical inaccuracy.

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 correctbecause Huawei utilizesGlobal Wear Levelingto distribute writes across all SSDs to extend their lifespan, andAnti-Wear Levelingto prevent multiple SSDs from reaching their end-of-life simultaneously, which avoids multi-disk failure risks.Option C is correctas the system supportsHyperMetro(Active-Active) for both block (SAN) and file (NAS) services, providing zero RTO and RPO across sites.Option D is correctbecause 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’s data protection solutions, particularly the OceanProtect and BCManager suites, support a wide range of backup targets to accommodate various Recovery Time Objectives (RTO) and Recovery Point Objectives (RPO).

Disk (Option C):This is the most common modern backup media (Disk-to-Disk or D2D), offering fast backup and recovery speeds. Huawei's OceanProtect is a dedicated high-speed disk-based backup storage.

Tape Library (Option D):Traditionally used for long-term archiving (D2D2T), tape remains a cost-effective and reliable "offline" storage medium for compliance and disaster recovery.

Disc (Option A):Optical discs (like Blu-ray) are used in specific archival scenarios where "Write Once" (WORM) physical media is required for regulatory purposes.

Cloud (Option B):Modern Huawei solutions supportBackup to Cloud, where data is deduplicated, compressed, and sent to an off-site object storage provider (like Huawei Cloud OBS) for cost-effective disaster recovery without the need for a physical secondary site.

Huawei’s 3DC (Three-Data-Center) solution is designed for high-level business continuity, typically involving a local HA site and a remote DR site. The documentation supports three main topological configurations to meet different reliability and performance needs:

Cascading Network (Option B):Site A (Production) replicates to Site B (Local DR), and Site B then replicates to Site C (Remote DR). This reduces the pressure on the production site (Site A) as it only manages one replication link.

Parallel Network (Option C):Site A replicates directly to both Site B and Site C simultaneously. This provides better protection for the data at Site C, but increases the load and bandwidth requirements on Site A.

DR Star Network (Option A):This is a specific variant of the multi-site protection architecture used in Huawei'sHyperMetro + Remote Replicationscenarios. It typically combines an active-active setup between Site A and B with an asynchronous link to Site C, ensuring that even if two sites fail, the third contains a survivable copy of the data.

Huawei’s Multi-protocol Lossless Interworking is a standout feature of the OceanStor Pacific series, allowing one copy of data to be shared across different protocols (File, Object, HDFS).

No Semantic or Performance Compromise (Option B):Historically, protocol conversion (e.g., using a gateway) led to performance loss or "semantic loss" where certain file attributes or object tags were dropped. OceanStor Pacific implements native support for multiple protocols at the metadata level, ensuring full semantic compatibility and high-speed access regardless of the protocol used.

Zero Data Copy (Option C):This feature allows one piece of data to be written via one protocol (e.g., ingested via S3) and read via another (e.g., analyzed via HDFS) without moving or copying the data to a separate system. This eliminates "data silos" and greatly improves data processing efficiency.

Gateway-free (Option D):Because the interworking is native to the storage OS, no external protocol gateways are required. This simplifies the management architecture and reduces the hardware footprint.

Option A is incorrectbecause documentation generally advises against mixing structured (Database) and unstructured data in the same pool for optimal performance, though the system is primarily optimized for unstructured workloads.

This statement is false because it confuses RTO (Recovery Time Objective) with RPO (Recovery Point Objective). In Huawei’s Disaster Recovery (DR) documentation, these two metrics are defined as follows:

RPO (Recovery Point Objective):Refers to the maximum amount of data loss an organization can tolerate, measured in time. It indicates the "point in time" to which data must be recovered (e.g., "we can only lose 1 hour of data").

RTO (Recovery Time Objective):Refers to the duration of time within which a business process must be restored after a disaster. It measures how long the system can be down before the business is significantly impacted (e.g., "the system must be back online within 4 hours").

The question describes the "point in time" (RPO) but labels it as RTO. In a high-availability solution likeHyperMetro, the RTO and RPO are both theoretically zero, meaning no data loss and no downtime.

According to Huawei’s technical documentation on storage media, Solid State Drives (SSDs) fundamentally differ from Hard Disk Drives (HDDs) in their physical construction and data access methods. HDDs rely on mechanical components, including rotating platters and moving read/write heads. This mechanical nature introduces "rotational latency" and "seek time," which inherently limit the number of Input/Output Operations Per Second (IOPS).

In contrast, Huawei’s OceanStor SSDs utilize flash memory chips (NAND Flash) and a high-performance controller. Because there are no moving parts, the "seek time" is eliminated, allowing for near-instantaneous data access. This results in significantly higher random IOPS and much lower latency (often measured in microseconds rather than milliseconds). Furthermore, Huawei’sFlashLink® technologyfurther optimizes the collaboration between the storage controller and the SSDs, ensuring that even as the drive fills up, the performance remains consistent and the latency remains low. Therefore, in any performance-oriented storage environment, SSDs are the preferred choice over traditional HDDs.

In the Huawei OceanStor RAID 2.0+ architecture, Redundant Array of Independent Disks (RAID) levels are used to balance performance, capacity, and reliability. RAID 0, also known as "striping," distributes data blocks across multiple physical disks to maximize I/O performance. By allowing multiple disks to be read or written simultaneously, it provides the highest throughput and capacity utilization (100%).

However, the defining characteristic of RAID 0 is the complete lack of redundancy. Unlike RAID 1 (Mirroring), RAID 5 (Parity), or RAID 6 (Dual Parity), RAID 0 does not store redundant information or parity bits. Huawei documentation explicitly states that if any single physical disk in a RAID 0 group fails, the entire RAID group becomes inaccessible, and all data within that group is lost. Therefore, RAID 0 is strictly recommended only for temporary data or scenarios where data loss is acceptable and maximum performance is the sole priority. For enterprise production environments, Huawei recommends RAID 5, RAID 6, or RAID-TP.

In Huawei OceanStor storage systems utilizing RAID 2.0+ and the SmartMatrix architecture, the "write penalty" associated with traditional RAID is mitigated through Full-Stripe Writes. In a partial write (where only some data in a stripe is updated), a RAID 5 setup usually suffers a write penalty of 4 (Reading old data, reading old parity, writing new data, writing new parity).

However, Huawei's controllers utilize a large cache to aggregate incoming data. When enough data is collected to fill an entire stripe (e.g., 8 data chunks plus 1 parity chunk in an 8+1 RAID 5 setup), the system performs aFull-Stripe Write. In this scenario, the system calculates the parity in the CPU/cache and writes the entire stripe to the disks at once. Since no old data or old parity needs to be read from the physical disks before writing, the disk-levelwrite penalty is 0. This significantly enhances the write performance of hybrid arrays, especially those using mechanical HDDs which are highly sensitive to the latency of extra read/write operations.

This statement reflects the architectural evolution of Huawei OceanStor systems. The Small Computer System Interface (SCSI) protocol was designed decades ago for mechanical drives (HDDs). It uses a single command queue with a depth of 32 commands, which was sufficient for the physical limitations of rotating platters and moving heads.

In contrast,Non-Volatile Memory express (NVMe)was designed specifically for flash media. It replaces the legacy SCSI stack to eliminate bottlenecks. NVMe supports up to 64,000 queues, each with 64,000 commands, allowing for massive parallelism. Huawei OceanStor Dorado (All-Flash) systems utilizeEnd-to-End NVMe(from the SSD to the controller, and from the controller to the host via NVMe-oF) to achieve microsecond-level latency. While modern flash arrays can still use SCSI (via FC or iSCSI) for compatibility, the full performance potential of an all-flash array is only realized through NVMe. Therefore, in modern storage design, SCSI is the legacy standard for HDDs/Hybrid arrays, while NVMe is the optimized standard for All-Flash arrays.