In Huawei object storage, permission management is commonly implemented through access control lists (ACLs) and bucket policies. A bucket policy can control access permissions for one or multiple users at the bucket level and can also define permissions for objects within the bucket. ACLs are also used to grant accounts access to storage resources, so option D is correct. The incorrect statement is option C because ACLs are mainly used to grant permissions rather than explicitly deny permissions. Deny logic and more complex access conditions are normally handled through bucket policies. This distinction matters in object storage because bucket policies provide more flexible permission rules, while ACLs provide simpler account-level authorization. Therefore, the incorrect statement is that ACLs can be used to grant and deny permissions.

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. While LDAP (Option A) and NIS (Option B) are supported by Huawei NAS for the NFS protocol (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.

Backup networking modes describe how backup data moves between production hosts, backup servers, storage systems, and backup media. LAN-Based backup sends backup traffic through the production Ethernet network, which is simple but may consume service bandwidth. LAN-Free backup moves backup traffic through a dedicated storage network, usually SAN, reducing pressure on the production LAN. SAN-Based backup uses SAN connectivity to improve backup throughput and isolate backup traffic from ordinary service traffic. Server-Free backup further reduces host involvement by allowing storage systems or backup infrastructure to move data more directly, minimizing the performance impact on application servers. Huawei data protection designs commonly classify backup networking by these modes because each mode has different cost, performance, complexity, and service-impact characteristics. Therefore, all four listed modes are valid backup networking modes.

Huawei’s object storage solution (OceanStor Pacific/OBS) is designed for massive scalability and high availability across geographic boundaries. Option C is correct because the Global Namespace feature abstracts the physical location of data, allowing users to access objects via a single URL/endpoint regardless of which Data Center or Availability Zone (AZ) the data physically resides in. This simplifies application development and data management at scale.

Options A and B are correct as the architecture supports multi-regional deployment. Data can be replicated between regions to ensure disaster recovery and data sovereignty. Unlike traditional SAN/NAS replication which is often limited by latency-sensitive synchronous protocols, object storage utilizes asynchronous transfer mechanisms optimized for the HTTP/S3 protocol. This leads to Option D being correct ; because object storage replication is typically asynchronous and handles high latency well, sites can be separated by thousands of kilometers, making it an ideal solution for global data distribution and remote site backup.

Huawei’s new-generation OceanStor hybrid flash storage systems (such as the 5000 and 6000 series) provide high-density snapshot capabilities to ensure data resilience against logical errors or malicious attacks. According to the technical specifications for these systems, the minimum intervals for secure snapshots differ between file and block services.

For SAN (Block) storage , the system can support high-frequency snapshots with a minimum interval of 3 seconds . This low interval allows for near-continuous data protection, enabling recovery points that are extremely close to the moment of a failure or attack. For NAS (File) storage , the minimum secure snapshot interval is 15 seconds . While slightly longer than the SAN interval, this still provides superior granularity for file-level recovery compared to traditional backup schedules that often run only once per day or hour. These " HyperSnap " and " HyperCDP " features ensure that mission-critical applications can be rolled back to a healthy state within seconds, significantly reducing the Recovery Point Objective (RPO) for both structured and unstructured data.

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 the SmartMatrix 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.

The statement is false because the NameNode in an HDFS architecture is not responsible for storing actual user data. HDFS consists mainly of a NameNode, multiple DataNodes, and clients. The NameNode manages the file system namespace, metadata, directory structure, file permissions, and block mapping information. It knows which DataNodes hold the blocks of each file, but it does not store the file data itself. The DataNodes are responsible for storing actual data blocks and handling read/write requests from clients under the coordination of the NameNode. In Huawei distributed storage scenarios, this distinction is important because metadata management and data storage are separated to improve scalability and reliability. Therefore, saying that the NameNode is responsible for data storage is incorrect.

Multi-tenancy is used in object storage to allow different departments, services, or customers to share one physical storage system while remaining logically isolated. Option B is correct because multiple departments can use the same platform instead of deploying separate storage silos. Option C is correct because each tenant can be assigned independent capacity quotas and performance QoS policies, preventing one tenant from consuming excessive resources or affecting another tenant’s service quality. Option D is also correct because tenants share the same backend storage pool, which improves overall resource utilization and reduces wasted capacity. Option A is incorrect because tenant isolation is a core purpose of multi-tenancy. One tenant should not be able to view or access another tenant’s data unless explicit authorization is configured.

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 a Full-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-level write 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.

OceanStor Dorado is Huawei’s all-flash storage platform positioned around performance, reliability, scenario coverage, and intelligent operations. Option A reflects the performance highlight: Dorado is designed for extremely high IOPS and ultra-low latency, making it suitable for databases, virtualization, core banking, and latency-sensitive enterprise workloads. Option B is also valid because Dorado covers both SAN and NAS scenarios and is positioned as a leading all-flash storage system across industries. Option C is correct because Dorado’s high-end SmartMatrix architecture and HyperMetro capabilities provide strong resilience, including controller-level fault tolerance for mission-critical services. Option D is correct because Huawei emphasizes intelligent O & M through cloud-based analytics, proactive risk identification, and simplified management. Together, these highlights describe Dorado’s value proposition: fast, reliable, broadly applicable, and intelligently managed.