Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Dell Midrange Storage Solutions Design 2023 > Midrange Storage Performance Planning: Storage Configuration Recommendations > Flashcards

Midrange Storage Performance Planning: Storage Configuration Recommendations Flashcards

1
Q

What are the supported types of pools in Unity XT?

A

dynamic and traditional

pools are preset to dynamic unless specified by admin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

When would you want to have separate storage pools on the same Unity system?

A

separate workloads with different IO profiles

separate pools where FAST Cache is and isn’t active

dedicate resources to meet specific performance goals

separate resources for multitenancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the recommended free capacity for a storage pool to maintain operations in a Unity XT?

A

10% free capacity

system automatically invalidates any snapshots or replications if free capacity is less than 5%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When does a Unity XT raise alerts for storage pools?

A

when there’s less than 70% free capacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are dynamic pools in Unity XT?

A

apply RAID to groups of drive extents from drives within the pool

allow for more flexibility and easier management

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the dynamic pool options on Unity XT?

A

Single Tier

Multitier - pool consisting of combination of drive types

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What type of pools does UnityVSA have?

A

only traditional pools

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do dynamic pools work in Unity?

A

combines the drives of the same type into a drive partnership group

at physical disk level systems splits disks into identical portions called drive extents

drive extents grouped into drive extent pool

drive extent pool used to create RAID extents

RAID extents grouped into RAID groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the role of drive extents in Unity dynamic pools?

A

hold a position of a RAID extent or used for space space in case of rebuild

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is a RAID extent in Unity dynamic pools?

A

collection of drive extents

selected RAID type/width determine number of drive extents within a RAID extent

each one contains single drive extent from a specific number of drives equal to the RAID width

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the result of the dynamic pool process in Unity?

A

creates a single private LUN for each RAID group by combining pieces of all RAID extents and striping them across the LUN

LUN partitioned into 256MB slices

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How much spare space can you allocate in Unity dynamic pools?

A

up to 2 spares per 32 drives

unbound drives of appropriate type can also be used in rebuild

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is true about the relationship between dynamic pools and performance?

A

there is no performance or availability advantage to using smaller RAID widths with dynamic pools

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the recommendations for drive minimums for different RAIDs in dynamic pools?

A

RAID 5 - 14 drives

RAID 6 - 17 drives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does spare space work with dynamic pools?

A

each drive extent pool reserves a specific percentage of extents on each disk as spare space

percentage of reserve capacity dependent on drive type and RAID type applied to the drive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens if there’s a drive failure within a dynamic pool?

A

spare space within the pool is used

handled automatically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is true about spare space and system capacity?

A

not counted towards usable capacity of the system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How much reserve space if in a dynamic pool at one time?

A

for every 32 drives of the same type within a pool there’s enough spare space to build back the largest drive in the pool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does dynamic pool expansion work in Unity XT?

A

can expand up to the system limits by one or more drives

new drive partnership group is created if the number of drives added exceeds maximum size of 64 drives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When is expansion of a dynamic pool not allowed in Unity XT?

A

if number of drives being added is not enough to fulfill the minimum drive requirements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the minimum number of drives to start a new drive partnership group?

A

RAID width + set spare space reservation (1-2 drives)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does adding drives within a drive partnership group do?

A

causes drive extents to rebalance across the new space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What happens when you add a single drive to a dynamic pool or a number of drives that is less than the RAID width of the pool?

A

system identifies extents that must be moved off drives to new drives as part of rebalancing process

frees up capacity on corresponding drives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the PACO feature on Unity XT?

A

proactive copy

enables disks to actively copy to a hot spare

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What happens if you add a single drive and the spare capacity boundary is crossed on a dynamic pool?

A

none of that drive’s capacity is added to the usable capacity of the pool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the process of adding multiple drives to a dynamic pool?

A

much faster than single drive add on

expansion process creates drive extents

system creates RAID extents and RAID groups and makes space available to users

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is true about mixing drives in dynamic pools?

A

drives of same type but different capacities can be mixed

not recommended - can’t do different drive types in same pool

28
Q

What happens when a new drive type is added to the system?

A

pool must be expanded with a minimum number of drives

must satisfy the RAID width + set spare capacity

29
Q

What is a traditional pool in Unity storage?

A

storage pools whose tiers are configured with traditional RAID groups

30
Q

How do you expand traditional pools in Unity?

A

only by adding RAID groups

31
Q

What is max number of drives you can have in a traditional pool in Unity?

A

16

32
Q

How can you configure traditional pools in Unity?

A

heterogenous

homogenous

33
Q

How does a heterogenous traditional pool work in Unity?

A

RAID group of both drive sets created

Private LUN created for each RAID group

private LUNs split into continuous array slices that are 256MB - hold user data and metadata

once private LUNs partitioned into slices they are consolidated into single pool called slice pool

34
Q

What is the relationship between FAST VP and heterogenous traditional pools in Unity?

A

moves slices to various tiers

35
Q

When are homogenous pools recommended in Unity?

A

for applications with limited skew - more predictable performance

36
Q

What are the RAID protection levels recommended by Dell for traditional pools?

A

RAID 5 - extreme performance/performance tiers

RAID 6 - capacity tier

37
Q

When does Dell recommend smaller RAID widths in traditional pools?

A

when configuring the same number of drives

smaller widths provide best performance/availability

38
Q

What is the recommended configuration for customers that want a RAID 1/0 in their Unity traditional pools?

A

1+1

offers better performance and flexibility with same availability

39
Q

How is spare space allocated with traditional pools in Unity?

A

use hot spares

1 hot spare every 31 drives

replaces faulty drive with same type and same or higher capacity drive

40
Q

What are important notes about all flash pools in Unity XT?

A

snapshots and replication operate more efficiently with AF pools

data reduction only enabled in AF pools

no FAST Cache/FAST VP

use only single drive size/RAID width in AF pools

41
Q

What is the drive size and width necessary for Unity XT AF pools?

A

1.6TB SAS Flash 3 w/ RAID 5 (8+1)

42
Q

What are the block storage resources supported by Unity XT?

A

LUNs

Consistency Groups

VMFS Datastores

vVol

43
Q

What is a LUN?

A

logical unit representing a piece of block storage that is allocated to a host

can be allocated to multiple hosts if coordinated through a set of clustered hosts

44
Q

What is a consistency group?

A

addressable instance of LUN storage that can contain one or more LUNs (up to 50)

associated to one or more FC or iSCSI hosts

snapshots of consistency groups apply to all LUNs in the group

45
Q

What are vVols?

A

virtual volumes

storage objects that are provisioned automatically by a VMWare framework to store VM data

46
Q

What are protocol endpoints?

A

establish a data path between ESXi host and respective vVol datastores

47
Q

What storage object does Unity XT provision by default and why is it recommended by Dell?

A

creates thin storage objects automatically but supports thick LUNs also

provide the best capacity utilization and are required for most features

48
Q

What features require thin storage objects to be used by Unity XT?

A

data reduction

snapshots

asynchronous replication

49
Q

What configuration does Dell recommend for best capacity utilization in Unity XT?

A

configuring objects at least 100GB in size - preferably 1TB

50
Q

What is a Powerstore volume?

A

single unit that represents a specific quantity of block storage that can be standalone or associated with a volume group

51
Q

What is the role of Powerstore volumes?

A

manage partitions of block storage resources so that the host system can mount and use these resources

52
Q

How are volumes created on Powerstore?

A

one volume or many can be created at a time

resource balancer automatically determines which appliance in the cluster the volume is provisioned

53
Q

What is the role of thin provisioning?

A

allows multiple storage resources to subscribe to a common storage capacity

allocates an initial quantity of storage - represents maximum capacity to which storage resource can grow without being increased

54
Q

What is the maximum and minimum size of storage volumes in Powerstore?

A

1MB - 256TBs

55
Q

What is every volume given in Powerstore?

A

a LUN

56
Q

What is a volume group in Powerstore?

A

logical container for a group of volumes

volume can only be member of one volume group at a time

57
Q

What is the purpose of a volume group in Powerstore?

A

provides single point of management for multiple storage resources that work together as a unit

58
Q

How are volume groups treated by the Powerstore system?

A

treats the volume group as a single entity

59
Q

What is a NAS Server with Powerstore?

A

virtual file server that provides file resources on the IP network and to which NAS clients connect to

allow access over NFS and SMB and FTP and SFTP

60
Q

What is a filesystem and how does Powerstore support them?

A

manageable storage object for file based storage with a specific size and file access protocols

Powerstore supports file system snapshots and thin clones of file systems

61
Q

How does Powerstore store containers?

A

store them and contain VMWare vVols

containers have 1:1 mapping w vVol datastories

62
Q

How does Powerstore communicate with VMWare for storage container storage?

A

communicates w/ vCenter server through VASA protocol

communication established through protocol endpoints

63
Q

What block protocols does Powerstore support?

A

FC, NVMe/TCP, NVMe/FC, iSCSI

hosts must access storage only using one of these protocols at a time

64
Q

What is dynamic node affinity in Powerstore?

A

block storage resources are dynamically rebalanced between nodes

65
Q

What are performance policies in Powerstore?

A

all block storage have a defined performance policy

by default this is set to medium

devotes less resources to low performance policy volumes during times of high utilization

66
Q

How are NAS servers distributed on Powerstore?

A

single NAS server uses compute resources from only one node of the Powerstore

recommended to create at least two NAS servers so resources from both nodes contribute to file performance

Dell Midrange Storage Solutions Design 2023 (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions