Module 4: Intelligent Storage Systems (Storage Tiering + Storage Provisioning)

Question 1

What is storage provisioning?

Answer 1

process of assigning storage to compute based on capacity. availability, and performance

Question 2

What are the two types of storage provisioning?

Answer 2

traditional
virtual

Question 3

What do LUNs do when it comes to storage provisioning?

Answer 3

hide organization and composition of RAID set from compute

Question 4

What are traditional provisioning LUNs called?

Answer 4

thick LUNs

Question 5

What is the relationship between RAID and traditional provisioning?

Answer 5

number of drives in RAID set and RAID level determin performance/capacity/availability

Question 6

What is a recommendation when building RAID groups?

Answer 6

create them from the same drive types, capacity, and speed

Question 7

What is virtual provisioning?

Answer 7

enables creating and presenting LUN with more capacity than is physically allocated on the storage system

Question 8

What are virtual provisioning LUNs called?

Answer 8

thin LUNs

Question 9

What are the requirements of thin LUNs?

Answer 9

dont’ need all the phyiscal storage to be allocated at the time of creation - only use physical storage as needed

Question 10

What makes thin LUNs different from thick LUNs?

Answer 10

thick LUNs require all the physical storage that is allocated to them at the time of creation to be presented to the compute

Question 11

What are the benefits of virtual provisioning?

Answer 11

more efficient storage allocation to compute

enables oversubscription

shared pool and thin LUN can be expanded nondisruptively as storage requirements of compute grows

multiple shared pools can be created within a storage system and a shared pool can be shared by multiple thin LUNs

Question 12

What is oversubscription?

Answer 12

more capacity is presented to the compute systems than is physically available

Question 13

What is the drawback of traditional provisioning?

Answer 13

typically based off anticipated storage requirements - can result in overprovisioning and overpayment

Question 14

When should you use thin LUNs over thick LUNs?

Answer 14

appropriate for applications that can tolerate performance variations

Question 15

What is storage tiering?

Answer 15

technique of establishing a hierarchy of storage types

Question 16

Why do storage tiering?

Answer 16

relocating data to the appropriate storage type to meet service level requirements at minimal costs

Question 17

What is intra-array storage tiering?

Answer 17

process of storage tiering within a storage system

Question 18

What is tiering at the LUN level?

Answer 18

moves entire LUN from one tier to another - does not give cost benefits

Question 19

What is tiering at the sub-LUN level?

Answer 19

LUN broken down into smaller segments and tiered at that level - provides effective cost and performance benefits

Question 20

What is tiering between storage systems?

Answer 20

data moved to secondary storage system or to the cloud

Question 21

How does tiering between storage systems start?

Answer 21

policy engine scans primary storage to identify data that meets policy window to tier off

Question 22

What happens after data is identified by storage systems for tiering?

Answer 22

pointers are created - data is moved to destination tier

Question 23

What is cache tiering?

Answer 23

enables creation of a large capacity secondary cache using SSD

Question 24

What does cache tiering do?

Answer 24

enables tiering between DRAM cache and SSD

Question 25

How are IOs processed in cache tiering?

Answer 25

most reads are served directly from high performance tiered cache - enhances performance during peak workloads