H19-308_V4.0 Questions and Answers

Huawei provides tailored solutions for Medical PACS based on the specific performance and scale requirements of healthcare providers. OceanStor Dorado NAS (Option D) is recommended for the "Hot Data" or active tier of a PACS system. Because medical images between 100 KB and 1 MB require high-concurrency access and extremely low latency for immediate clinical review, the FlashLink® technology and all-flash architecture of the Dorado series provide the necessary IOPS to prevent bottlenecks during peak hours.

OceanStor Pacific (Option C)is the primary recommendation for the massive, long-term unstructured data storage required by PACS. A single hospital can generate petabytes of data over several years. OceanStor Pacific’s scale-out architecture allows it to handle billions of small files efficiently using a global namespace, and its high-ratio Erasure Coding (EC) ensures maximum capacity utilization and lower TCO for archives. While Hybrid Flash (Option A) can be used, it is often superseded by the superior performance of Dorado or the superior scalability of Pacific in modern medical environments. FusionCube (Option B) is an HCI solution more suited for edge computing or virtualization rather than specialized, large-scale medical imaging repositories.

In Huawei OceanStor systems, a snapshot is not a full physical copy of the data. Huawei uses a technology called HyperSnap, which typically employs a "Copy-on-Write" (COW) or "Redirect-on-Write" (ROW) mechanism.

When a snapshot is created, the system generates a point-in-time (PIT) logical image of the source LUN. It does not immediately duplicate the data blocks; instead, it records the state of the data at that specific moment. If data in the source LUN is subsequently modified, the original data is preserved (in COW) or new data is written to a new location (in ROW) to maintain the integrity of the snapshot. Because only the metadata and the changed blocks are managed, snapshots are created near-instantaneously and consume very little initial space.

A "full copy" would be referred to as aClone (HyperClone)or aLUN Copy, both of which require a 1:1 ratio of physical storage space relative to the source and take significant time to complete. Therefore, a snapshot is a virtual, point-in-time image, not a full physical duplicate.

According to the Huawei OceanStor Pacific series data sheet and reliability manuals, the system utilizes Elastic Erasure Coding (EC) for data redundancy protection. This technology is more efficient than traditional RAID and allows for higher levels of tolerance in a distributed environment.

Specifically, a single OceanStor Pacific storage system can be configured to tolerate the simultaneousfailure of up to four nodes(or four cabinets in a multi-cabinet deployment) without data loss or service interruption. When a node fails, the system automatically triggers a background reconstruction process to restore redundancy using the remaining healthy nodes. The flexibility of dynamic EC ratios (N+M) allows the system to adjust to these faults while maintaining optimal space utilization and reliability.

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.

Huawei OceanProtect utilizes source deduplication to optimize the data protection process. In traditional backup scenarios, the entire dataset is sent over the network to the backup target, which can consume significant bandwidth and time. With source deduplication, the storage system or backup agent identifies redundant data blocks at the source—before they are sent over the network.

By comparing new data chunks against a local cache of already-transmitted fingerprints, the system ensures that only unique, non-duplicate data is physically moved across the production-to-backup link. This significantlyreduces network bandwidth consumptionand effectively increases thelogical backup bandwidth, as the system can process larger volumes of data without being limited by physical network throughput. Consequently, thebackup window is shortened, allowing organizations to meet tight RPOs even in environments with limited network resources or massive data growth.

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.

The SMB (Server Message Block) protocol, which is primarily used for Windows-based file sharing, relies on a centralized authentication and authorization mechanism to manage permissions in an enterprise environment. In Huawei OceanStor NAS documentation, Active Directory (AD) is the primary domain controller system supported for the SMB protocol.

When a Huawei storage system joins an Active Directory domain, it can authenticate users and groups defined in the AD, allowing for seamless integration with Windows environments. WhileLDAP (Option A)andNIS (Option B)are supported by Huawei NAS for theNFSprotocol (typically used in Linux/Unix environments), the SMB protocol is inherently designed to work with the Kerberos and NTLM authentication provided by Microsoft’s Active Directory. This ensures that NTFS-style ACLs (Access Control Lists) can be properly mapped and enforced across the network.

NVMe over Fabrics (NVMe-oF) using the RoCE v2 (RDMA over Converged Ethernet) protocol is a high-speed communication technology supported by Huawei OceanStor Dorado systems. Option B is correct because RoCE v2 utilizes RDMA, which allows data to be transferred directly from the memory of one computer to another without involving the CPU of either system. This significantly reduces latency and CPU overhead compared to traditional iSCSI.

Option C is correctbecause RoCE v2 requires a "Lossless Ethernet" environment to function correctly. Traditional Ethernet (Option A) is a "best-effort" delivery system that allows for packet drops during congestion; however, RDMA protocols are highly sensitive to packet loss. To support RoCE v2, the network must implement Data Center Bridging (DCB) features like Priority Flow Control (PFC) and Enhanced Transmission Selection (ETS) to ensure a zero-packet-loss environment. Regarding cost (Option D), RoCE v2 often leverages existing Ethernet infrastructure, making it generally more cost-effective than deploying a dedicated Fibre Channel (FC) fabric, which requires specialized HBAs and FC switches.

Unlike traditional storage architectures that use an Asymmetric Logical Unit Access (ALUA) model where a LUN is "owned" by a primary controller, Huawei OceanStor Dorado utilizes a Symmetric Active-Active architecture. In this design, LUNs do not have a specific owner. Instead, all controllers in a cluster can simultaneously receive and process I/O requests for the same LUN.

This is made possible by theSmartMatrix full-mesh interconnect, which allows any interface module to communicate with any controller, and any controller to access any disk. Because there is no concept of "LUN ownership," there is no need for time-consuming "LUN handovers" if a controller fails. This symmetry eliminates performance bottlenecks, ensures balanced load distribution across all hardware resources, and provides a smoother experience for host-side multipathing software. This architectural shift is a key differentiator for the Dorado series, enabling it to deliver consistent, high-speed performance even during controller maintenance or failure.

Huawei OceanStor Dorado utilizes RAID 2.0+ block virtualization technology, which supports Dynamic RAID Reconstruction. In a traditional RAID environment, if a disk fails, the RAID group continues to operate in a "degraded" mode until the disk is replaced. However, in Dorado's RAID 2.0+, the system uses a distributed spare space policy where spare capacity is spread across all disks in the pool.

When one SSD fails in a storage pool originally configured with RAID 6 (7 data chunks + 2 parity chunks), the system identifies that it no longer has enough physical disks to maintain a 7+2 stripe width. To maintain the same level of protection (dual parity) while utilizing the remaining 8 disks, the system dynamically adjusts the RAID policy for new writes and reconstructed data toRAID 6 (6+2). This ensures that the data remains protected by two parity chunks even with a reduced disk count. This "shrinkage" of the stripe width allows the system to remain in a "healthy" protected state rather than staying in "degraded" mode indefinitely.

Direct-Attached Storage (DAS) is a traditional storage architecture where storage devices are connected directly to a host server. Huawei documentation defines the following key characteristics:

Direct Connection (Option C):DAS connects to the server via internal or external interfaces such as SATA, SAS, or SCSI, rather than through a storage network.

No Network Devices (Option A):Because it is a 1-to-1 connection, it does not require Fibre Channel switches or Ethernet switches to facilitate the link between the host and the storage. This makes it simple and cost-effective for small-scale deployments.

Block Storage Services (Option B):Like a SAN, DAS provides block-level access. The server’s operating system manages the file system (NTFS, EXT4, etc.) directly on the provided blocks.

While a server attached to DAS can share its files over a network (becoming a file server), the DAS itself is not a "File Storage Service" (Option D). In Huawei’s hierarchy, file services are the domain ofNAS (Network Attached Storage), which provides shared access to files via protocols like CIFS/SMB or NFS.

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.

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.