Select and Install Storage Devices Flashcards
3.3 Given a scenario, select and install storage devices.
Storage devices that hold data when the system is powered off
Non-volatile storage devices
What are the 3 types of mass storage technologies?
magnetic, optical, or solid-state technology
A mass storage device installed as an internal component
Fixed disk
Allows you to fit a drive of a different size to the bay
Adapter caddy
What are the standard widths of storage devices?
5.25 inches, 3.5 inches, and 2.5 inches
uses flash memory technology to implement persistent mass storage; Risks from total failure of the device due to mechanical shock and wear are generally lower. Costs per gigabyte have fallen rapidly in the last few years
Solid-state drive (SSD)
evenly distribute writing on all blocks of an SSD to optimize the life of the device
wear leveling
Form factor communications interface with 600 MBps to plug in an SSD to a combined data and power port
mSATA
What is the transfer rate to a SSD?
6.7 GB/s
stores data on metal or glass platters that are coated with
a magnetic substance. The top and bottom of each platter is accessed by its own read/write head, moved by an actuator mechanism. The platters are mounted on a spindle and spun at high speed. Each side of each platter is divided into circular tracks, and a track contains several sectors
Hard disk drive (HDD)
What is the capacity of a sector on an HDD?
512 bytes
What are the average speeds of an HDD in rpm?
7,200 or 5,400 rmp
What are the speeds of a high performance HDD?
15,000 or 10,000 rpm
What are the two main form factors for HDDs?
3.5” for desktop PCs; 2.5” for laptops and as external drives
To mitigate the risks of data loss, the disks that underpin the mass storage system can be provisioned as this type of drive configuration
redundant array of independent disks (RAID
Drive configuration that divides data into blocks and spreads the blocks in a fixed order among all the disks in the array. This improves performance as multiple disks are available to service requests in parallel; aka striping without parity
RAID 0
How many disks does a RAID 0 drive configuration need?
at least 2 disks
What is the logical volume size of a RAID 0 drive configuration?
the total of the smallest capacity physical disk
a mirrored drive configuration using two disks; Each write operation
is duplicated on the second disk in the set, introducing a small performance overhead. A read operation can use either disk, boosting performance somewhat. This strategy is the simplest way of protecting a single disk against failure. If one disk fails, the other takes over
RAID 1