DEA-1TT5 Storage Systems Fundamentals 1 — Questions and Answers
Question 1: What is the primary difference between DAS, NAS, and SAN storage architectures?
- DAS is directly attached to a host, NAS provides file-level access over a network, SAN provides block-level access over a dedicated network (Correct answer)
- DAS uses fiber channel, NAS uses SCSI, SAN uses Ethernet
- DAS is the fastest, NAS is the slowest, SAN is medium speed
- DAS supports multiple hosts, NAS supports one host, SAN supports two hosts
Correct answer: DAS is directly attached to a host, NAS provides file-level access over a network, SAN provides block-level access over a dedicated network
DAS connects directly to a single host, NAS offers file-level (NFS/SMB) network access, while SAN delivers block-level storage over a dedicated high-speed network.
Question 2: Which storage media type uses NAND flash memory and has no moving parts?
- HDD
- SSD (Correct answer)
- Tape
- Optical disk
Correct answer: SSD
SSDs (Solid State Drives) use NAND flash memory with no mechanical moving parts, offering faster access times and greater durability than HDDs.
Question 3: In the context of storage, what does IOPS stand for?
- Input/Output Processing Speed
- Input/Output Operations Per Second (Correct answer)
- Internal Operations Per Session
- Integrated Output Processing System
Correct answer: Input/Output Operations Per Second
IOPS (Input/Output Operations Per Second) is a standard measure of storage device performance indicating how many read/write operations can occur each second.
Question 4: What is the purpose of a storage controller in a storage array?
- To provide power to the disk drives
- To manage data placement, caching, and I/O operations between hosts and disks (Correct answer)
- To physically protect the disk enclosure
- To connect the storage array to the internet
Correct answer: To manage data placement, caching, and I/O operations between hosts and disks
A storage controller manages all data operations including caching, I/O scheduling, RAID processing, and communication between the host systems and disk drives.
Question 5: Which of the following best describes 'tiered storage'?
- Storing data on multiple vendors' systems simultaneously
- Organizing data across different storage media based on performance needs and cost (Correct answer)
- Encrypting data at multiple layers
- Replicating data to multiple geographic locations
Correct answer: Organizing data across different storage media based on performance needs and cost
Tiered storage places frequently accessed (hot) data on high-performance media and less-accessed (cold) data on lower-cost, slower media to optimize cost and performance.
Question 6: What is 'latency' in the context of storage systems?
- The total capacity of a storage device
- The time delay between a request and the fulfillment of that request (Correct answer)
- The number of simultaneous connections supported
- The data transfer rate in MB/s
Correct answer: The time delay between a request and the fulfillment of that request
Latency is the time elapsed between when a storage I/O request is issued and when the data is delivered, typically measured in milliseconds or microseconds.
DEA-1TT5 Storage Systems Fundamentals 1
What is the primary difference between DAS, NAS, and SAN storage architectures?