CDCP Storage Data Center 3 — Questions and Answers
Question 1: Which type of storage media offers the lowest latency for random read/write operations in a data center?
- 7200 RPM SAS HDD
- NVMe SSD (Correct answer)
- LTO Tape
- SATA HDD
Correct answer: NVMe SSD
NVMe SSDs connect directly via PCIe, bypassing legacy storage controllers, and deliver microsecond-level latency far below any spinning disk.
Question 2: What is the role of a storage virtualization layer in a data center?
- To provide physical separation between SAN and NAS traffic
- To abstract physical storage resources and present them as logical volumes to hosts (Correct answer)
- To compress all data before writing to disk
- To manage Fibre Channel zoning configurations
Correct answer: To abstract physical storage resources and present them as logical volumes to hosts
Storage virtualization abstracts underlying physical hardware, allowing administrators to manage logical volumes independent of specific physical devices.
Question 3: In a data center context, what does 'thin provisioning' allow storage administrators to do?
- Allocate all storage capacity upfront to guarantee performance
- Allocate logical storage capacity that exceeds the currently available physical capacity (Correct answer)
- Limit storage growth by capping logical volume sizes
- Stripe data across the minimum number of drives to save power
Correct answer: Allocate logical storage capacity that exceeds the currently available physical capacity
Thin provisioning presents more logical capacity to hosts than physically exists, consuming real space only as data is actually written.
Question 4: What is the primary advantage of using Fibre Channel (FC) over iSCSI for SAN connectivity?
- FC is less expensive to deploy and manage
- FC provides lower latency and dedicated bandwidth not shared with LAN traffic (Correct answer)
- FC supports larger maximum transfer unit sizes
- FC is compatible with NAS protocols out of the box
Correct answer: FC provides lower latency and dedicated bandwidth not shared with LAN traffic
Fibre Channel uses a dedicated, lossless fabric that delivers consistent low-latency performance without competing with general network traffic.
Question 5: Which storage architecture allows multiple servers to access a shared file system simultaneously over a network?
- DAS (Direct Attached Storage)
- SAN with block volumes
- NAS (Network Attached Storage) (Correct answer)
- JBOD enclosure
Correct answer: NAS (Network Attached Storage)
NAS provides file-level access over standard networking protocols like NFS and SMB, enabling concurrent shared access by multiple clients.
Question 6: What is the purpose of a hot spare drive in a RAID array?
- To increase read performance through additional striping
- To automatically replace a failed drive and trigger array rebuild without manual intervention (Correct answer)
- To store parity data independently from the active drives
- To cache frequently accessed data for faster retrieval
Correct answer: To automatically replace a failed drive and trigger array rebuild without manual intervention
A hot spare remains idle in the array and is automatically incorporated to rebuild the RAID set immediately upon detection of a drive failure.
Question 7: What is the function of zoning in a Fibre Channel SAN?
- To segment physical drives into separate RAID groups
- To control which hosts can communicate with which storage targets on the fabric (Correct answer)
- To balance I/O loads across multiple storage controllers
- To schedule backup jobs based on time zones
Correct answer: To control which hosts can communicate with which storage targets on the fabric
FC zoning restricts fabric communication between specific HBAs and storage ports, providing security isolation and preventing unintended access.
CDCP Storage Data Center 3
Which type of storage media offers the lowest latency for random read/write operations in a data center?