FLASH CARDS

1.05 Select and Install Storage Devices

  • What is a mass storage device?

  • A non-volatile storage device that retains data even when the computer is turned off. It can use magnetic, optical, or solid-state technology.

  • What are fixed disks, and where are they installed?

  • Fixed disks are storage devices installed inside a computer. They come in sizes like 5.25, 3.5, and 2.5 inches and are secured in drive bays using caddies.

  • What factors should be considered when choosing a storage device?

  • Reliability, performance (read/write speed), and intended use (speed or capacity).

  • Name some common brands of mass storage devices.

  • Seagate, Western Digital, Hitachi, Fujitsu, Toshiba, and Samsung.

  • How do SSDs store data?

  • SSDs use flash memory technology for persistent storage, making them faster and more reliable than traditional hard disk drives (HDDs).

  • What is wear leveling in SSDs?

  • A technique used to evenly distribute data writing across all memory cells, counteracting the degradation of NAND flash memory over time.

  • What interfaces do SSDs use for connection?

  • SSDs can connect via 2.5-inch SATA, mSATA, PCIe, or M.2 form factors.

  • What is the maximum speed of a PCIe SSD using NVMe?

  • Up to 6.7 GB/s.

  • What precautions should be taken when handling SSDs?

  • Anti-electrostatic discharge (anti-ESD) measures to avoid damaging sensitive components.

  • How do HDDs store data?

  • HDDs use magnetic technology to store data on spinning metal or glass platters, accessed by read/write heads.

  • What factors influence the performance of an HDD?

  • RPM (revolutions per minute), seek time (time to locate a track), and rotational latency (delay due to sector location on spinning platters).

  • What are common RPM speeds for HDDs?

  • 15,000, 10,000, 7,200, and 5,400 RPM.

  • What interface is most commonly used by modern HDDs?

  • SATA.

  • What is removable storage?

  • Storage devices or media that can be easily moved between computers, such as USB drives, external HDDs/SSDs, and memory cards.

  • What are common interfaces for connecting external storage devices?

  • USB, Thunderbolt, and eSATA.

  • What types of memory cards are used in devices like cameras and smartphones?

  • SD, SDHC, SDXC, and microSD cards.

  • How do optical drives store data?

  • Using lasers to read and write data on discs like CDs, DVDs, and Blu-ray Discs.

  • What are the capacities of different optical discs?

  • CDs hold up to 700 MB, DVDs up to 17 GB, and Blu-rays up to 25 GB per layer.

  • How are optical drives installed and connected?

  • Internal optical drives fit into a 5.25-inch drive bay and connect via SATA. External drives connect through USB, eSATA, or Thunderbolt.

  • What is RAID, and what is its purpose?

  • A system that combines multiple HDDs or SSDs to provide data redundancy and fault tolerance, preventing data loss if a drive fails.

  • What is the main difference between software and hardware RAID?

  • Software RAID is managed by the operating system, while hardware RAID uses a dedicated controller card for improved reliability and support for more RAID levels.

  • What is a key advantage of using hardware RAID controllers?

  • They support hot swapping, allowing failed drives to be replaced without shutting down the system.

  • What are the requirements and benefits of RAID 0 (Striping without Parity)?

  • Requires at least two disks. Provides faster performance by splitting data into blocks across multiple disks but offers no data redundancy.

  • What are the requirements and benefits of RAID 1 (Mirroring)?

  • Requires exactly two disks. Duplicates all data for fault tolerance, allowing data recovery if one disk fails, but reduces usable storage capacity by half.

  • What does RAID 5 (Striping with Distributed Parity) offer?

  • Stripes data across multiple disks while distributing parity information for data recovery. Requires at least three disks and offers a good balance of performance and disk utilization.

  • What is the advantage of RAID 10 (Stripe of Mirrors)?

  • Combines RAID 1 (mirroring) and RAID 0 (striping) to provide excellent performance and fault tolerance, but with a high cost due to 50% storage overhead.

  • Why should disks in a RAID array ideally be the same size and type?

  • To ensure optimal performance. If disks differ in size, the smallest disk sets the maximum usable capacity across the array.

  • What is the impact on data when using RAID 0 if a disk fails?

  • All data in the array is lost because RAID 0 does not provide any redundancy.

  • What is the minimum number of disks required for RAID 10?

  • Four disks, and the number must be even.

  • SSD (Solid-State Drive)

  • A type of storage device that uses flash memory to store data. It has no moving parts, offering faster read/write speeds but limited write cycles.

  • HDD (Hard Disk Drive)

  • A type of storage device that uses mechanical platters and a moving read/write head to access data. Prone to mechanical failure over time.

  • Hot Swapping

  • The ability to replace a failed disk in a RAID array without shutting down the system.

  • RAID 0

  • A RAID level that stripes data across multiple drives to increase speed but provides no redundancy. A single drive failure results in data loss.

  • Mirroring

  • A RAID technique that duplicates data on two or more drives to provide redundancy and data protection.

  • Parity

  • A RAID technique that stores extra information to allow data recovery from failures, typically without mirroring the entire data set.