DEA-1TT5 Storage Networking (SAN and NAS) 2 — Questions and Answers
Question 1: What is 'LUN masking' in a SAN environment?
- Encrypting the LUN data to prevent unauthorized access
- A method to restrict which host initiators can access specific LUNs on the storage array (Correct answer)
- Hiding LUNs from the storage management interface
- Compressing LUN data to reduce capacity usage
Correct answer: A method to restrict which host initiators can access specific LUNs on the storage array
LUN masking is configured on the storage array to control which HBA WWNs (World Wide Names) can see and access specific LUNs, providing access control at the storage level.
Question 2: What protocol allows block storage to be accessed over a standard IP/Ethernet network without specialized FC hardware?
- NFS v4
- iSCSI (Correct answer)
- CIFS
- NDMP
Correct answer: iSCSI
iSCSI transports SCSI block storage commands over standard TCP/IP networks, allowing block-level SAN access using commodity Ethernet infrastructure and software initiators.
Question 3: In NAS architecture, what is a 'clustered NAS'?
- Multiple NAS arrays connected via Fibre Channel
- A NAS solution that distributes file serving across multiple nodes sharing a common namespace and storage pool (Correct answer)
- A NAS device optimized for cluster computing workloads
- Two NAS devices in an active-passive failover pair
Correct answer: A NAS solution that distributes file serving across multiple nodes sharing a common namespace and storage pool
Clustered NAS aggregates multiple nodes into a single system sharing a global namespace, enabling scale-out capacity and performance while providing node-level fault tolerance.
Question 4: What is the purpose of MPIO (Multipath I/O) in a SAN environment?
- To create multiple RAID groups simultaneously
- To manage multiple physical paths between a server and storage for failover and load balancing (Correct answer)
- To enable a single port to carry multiple protocols
- To partition a SAN fabric into isolated security zones
Correct answer: To manage multiple physical paths between a server and storage for failover and load balancing
MPIO software aggregates multiple physical paths to storage, providing automatic failover to an alternate path if one fails and optionally distributing I/O load across available paths.
Question 5: What is a 'VSS' (Virtual Storage Server) or SVM (Storage Virtual Machine) in modern NAS systems?
- A physical storage appliance virtualized in VMware
- A logical partition of a storage cluster's resources that provides independent storage services with its own namespace and protocols (Correct answer)
- A virtual machine used to manage storage arrays
- A snapshot of a storage volume used for backup
Correct answer: A logical partition of a storage cluster's resources that provides independent storage services with its own namespace and protocols
An SVM (Storage Virtual Machine) is a logical partition within a clustered storage system, providing isolated namespaces, network interfaces, and storage resources for multi-tenancy.
Question 6: Which storage access method does object storage use?
- Block-level access via SCSI
- File-level access via SMB/NFS
- REST API-based access using HTTP/HTTPS with a flat namespace (Correct answer)
- Direct DRAM access via RDMA
Correct answer: REST API-based access using HTTP/HTTPS with a flat namespace
Object storage exposes data through REST APIs (like S3 or Swift) using HTTP/HTTPS, organizing data as objects with metadata in a flat namespace rather than hierarchical directories.
DEA-1TT5 Storage Networking (SAN and NAS) 2
What is 'LUN masking' in a SAN environment?