1. Basic Concepts and Terminology
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Basic Concepts and Terminology
Module 8
U4879S L.01
HP Education Services
U4879S L.01

2. Managing HP Enterprise Virtual Array
Objectives
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Define the terms associated with an EVA
Identify the primary features of a disk group
Identify the primary features of virtual disks
Describe distributed virtual RAID technology
Describe virtual disk creation
Discuss storage presentation, hosts and LUNs
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

3. Virtual storage terminology overview
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Terms associated with the EVA:
storage system — an initialized pair of HSV controllers with a minimum of eight physical disk drives (six for SSDs), also called “storage cell”
disk group — a collection of physical disks of the same type (FC, FATA, or SSD) from which virtual disks are created
virtual disk — a logical disk with certain characteristics, residing in a disk group
host — a collection of fibre channel host bus adapters that reside in the same (virtual) server
selective storage presentation — EVA data security model
logical unit number (LUN) — a virtual disk selectively presented to one or multiple hosts
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

4. Power-on sequence (initial)
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Apply power to each PDU
Wait 3 minutes for disks to spin up
Loop switches boot up with disks
Wait additional time if FC switches are within the EVA rack (approximately 8–10 minutes)
Normal to have drive 1 failure indicator lit
Apply power to top (upper) controller
Assigned primary controller role
Becomes the “A” controller
Apply power to bottom (lower) controller
Assigned secondary controller role
Becomes the “B” controller
Enter WWN and checksum into top controller
During initial setup only
For EVA4400:
Apply power to drive shelves – wait for ready
Apply power to controller shelf – both controllers come up together
No switches or other components to power up
WWID – three places in the configuration; if needed, set with WOCP
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

5. Managing HP Enterprise Virtual Array
Storage system
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
An initialized pair of HSV controllers with a minimum of eight physical disk drives (six for SSDs)
Requires a name; can be up to 24 characters long
Special characters not allowed (for example, ?, “, /, \)
Two consecutive spaces not allowed
Name may be changed later
System initialization
After power-up sequence and controller initialization
Binds controllers as operational pair
Makes storage system ready for use
Creates first (default) disk group (minimum 8 disks, 6 SSD)
Establishes preliminary data structures and metadata
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

6. Storage system metadata
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Created during system initialization
Stored on quorum disks and contains:
Controller information
WWN and cell name
Character map of disk groups and virtual disk members
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

7. Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Disk Groups
U4879S L.01

8. Managing HP Enterprise Virtual Array
Disk group
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Named collection of physical disks
Minimum number of physical disks is 8 (6 for solid state drives)
Maximum number is number of drives present in the array
Unassigned or new disks may be added to an existing group or a new disk group may be created
Drives must be the same type; online FC, near-online FATA or SSD
Mixed drive sizes/speeds allowed
Can be normal or enhanced (EVA4400/6400/8400 only)
Capacity used to create virtual disks
Has a protection level (reserved spare) to allow for a single or double disk failure event of disks containing VRAID1
Reserved disk group space for single or double disk failures
Default protection level is Single
Instructor notes
FATA and FC disks cannot be mixed within a disk group. FC disk size can vary within a group, but due to protection level reserves this is not always best; don’t go into detail on the protection levels; this will be covered in more detail later in another module. Caveats are that more reserve capacity is required for single/double protection if larger disks are added into a disk group that already contains smaller disks; also no mixing of FATA and FC in the same disk group.
Again point out a naming convention easy to use here for the later labs.
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

9. Disk failure protection levels
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Allocates (reserves) disk space in a disk group to recover from physical disk failures (guaranteed sparing)
Three disk failure protection levels:
None — Reserves no physical disk capacity
Unassigned capacity, if available, is used
Single — Reserves enough unassigned spare capacity to recover from a single disk failure (largest spindle)
Requires capacity of two disks to recover full single VRAID1 Vdisk
Data relocated to paired drives
Double — Reserves enough unassigned spare capacity to recover from a double disk failure (largest spindle)
Requires capacity of four disks to recover full dual VRAID1 disks
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

10. Managing HP Enterprise Virtual Array
Default disk group
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
First disk group created
Used like any other disk group
May be renamed
Minimum: 8 disks (6 for SSD)
Maximum: all available disks
May be extended by adding more disks
Contains 5 quorum disks (initially)
Holds storage system metadata
Holds disk group metadata
Transferred to other disk groups one at a time
May be deleted only after another disk group is created
Protects metadata
Default disk group Q
Instructor notes
SmartStart EVA for the 4400 will configure all available drives in to one disk group, unless there are both FC and FATA drives installed, in which case Smartstart will create 2 disk groups.
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

11. Managing HP Enterprise Virtual Array
Disk group metadata
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Copied to the quorum disks in the default disk group
Maximum of 16 quorum disks (one per disk group)
Approximately 0.2% of total disk group capacity
When a new disk group is created
One quorum disk is created in it
One quorum disk is removed from the default disk group
Continues until just one quorum disk remains in the default group
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

12. Managing HP Enterprise Virtual Array
Disk group capacity
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Physical capacity of assigned disks (minus overhead)
Two types of disk group capacity
Assigned capacity in GB
Existing virtual disks
Sparing; space reserved for the protection level (single, double)
Unassigned capacity in GB
Used for:
Creating new virtual disks
Freeing a physical disk for removal or reassignment (leveling)
Data reconstructing after disk failure (sparing)
Increases when virtual disks are deleted or new physical disks are added to disk group
Sparing occurs if either of the following is true:
Sufficient unassigned capacity is available
Capacity is reserved as the protection level
Assigned
Reserved
Disk group
capacity
Unassigned
Instructor notes
Don’t go into usage details for sparing, business copies, etc. Focus on the concept of assigned vs. unassigned capacity.
disk group
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

13. Disk group (vertical configuration) Gen 3/4 example (2C4D)
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Alternates allocating disks from left side, then right, then left, etc.
Shelf 1
Shelf 2
Instructor notes
The TechBB and several white papers provide access to some detailed instructions on creating vertical disk groups and configuring arrays for a robust availability configuration.
This is a gen 3/4 example vs. older versions of the class material. Note that in the student book it will be black and white so they will not be able to see the colors this should be explained when teaching the class by the instructor. You may also want to go over the Gen 1 and 2 m5314 models with the 14 shelves.
Shelf 3
Shelf 4
Left hand disk group created of 16 disks created first
Right hand disk group of 8 disks created second
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

14. Disk group (vertical configuration) Gen 1/2 example
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
32-member disk group, default distribution assuming:
8 drive shelves
14 drives per shelf
Alternates allocating disks from left side, then right, then left, etc.
Disk Group
Drive Shelf
Instructor notes
Main concept is the physical distribution that is automatically performed by the EVA controllers; so no manual intervention for failure separation is necessary.
Drive slot
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
uc420s g.10
U4879S L.01

15. Managing HP Enterprise Virtual Array
Enhanced Disk Group
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Allows VRAID6 support
Available only for EVA4400/6400/8400 models with at least XCS
Requires HP Command View EVA 9.0 or higher.
Can simultaneously contain virtual disks of all supported Vraid types
The legacy disk group type supports all Vraid types except for Vraid6.
The disk group type is set at the time of creation and cannot be changed after that time
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

16. Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Vdisks
U4879S L.01

17. Managing HP Enterprise Virtual Array
Virtual disk (1 of 2)
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
A logical disk residing within a disk group
Proportionately spans all volumes of the disk group (striped)
Assigned (presented) to a host as a LUN
Features include
Size
Created in 1GB increments
Minimum size of1GB
Maximum size up to 32TB (2TB for Generation 2 arrays)
Redundancy levels
Very high — VRAID6 (striping with double parity, Gen 3/4 only)
High — VRAID1 (striping with mirroring)
Moderate — VRAID5 (striping with parity)
None — VRAID0 (striping)
Cache policies
Preferred path/controller mode
Write protection
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

18. Managing HP Enterprise Virtual Array
Virtual disk (2 of 2)
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Maximum of 2048 virtual disks (EVA6400/8400 only) per system
XCS and higher
Maximum of 1024 virtual disks per system for these firmware revisions:
XCS 6.1xx/6.2xx (Gen 2 arrays)
XCS versions lower than for EVA6400/8400
XCS 0952x000 and above for EVA4400
VCS 4.1xx (Gen 1 arrays)
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

19. Distributed virtual RAID (VRAID) technology
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Controller and XCS enable disk virtualization
Supports virtual disks of varying capacity (GB) and VRAID types
Virtual disk data is distributed across all disks in disk group
No stranded capacity (as in the traditional RAID set)
SCSI bus 1
SCSI bus 2
SCSI bus 3
SCSI bus 4
SCSI bus 5
SCSI bus 6
Traditional RAID sets
Instructor notes
Contrast VRAID to traditional RAID sets; VRAID = NO stranded capacity in the wrong RAID set.
RAID5 or RAID6 volume
RAID0 volume
RAID1 volume
Distributed VRAID
(disk group)
Highly redundant volume (VRAID1)
Moderately or highly redundant volume (VRAID5 or VRAID6)
No redundancy volume (VRAID0)
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

20. Managing HP Enterprise Virtual Array
Vdisk attributes
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Cache policies
Write cache
Mirrored (non-modifiable)
Write-back
Write-through (transition mode for clone operation)
Read cache
On (best practice)
Off
Preferred path/controller mode settings
No preference
Controller A/Failover only (used with multipath software)
Controller B/Failover only (used with multipath software)
Controller A/Failover-Failback
Controller B/Failover-Failback
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

21. Virtual disk expansion
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Volume expansion after creation
Capacity may be increased
Capacity may be decreased (XCS 6.1+)
Online volume growth (depends on OS support)
Available for Microsoft Windows
Requires HP Storage Volume Growth or Microsoft diskpart
Supported HP-UX with VXVM 4.1
Works on Linux with parted
Works on Sun Solaris with the growfs command
Support on other operating systems depends on OS capability
Some workarounds available
Refer to the EVA documentation for additional information
Online volume shrink (depends on OS support)
Windows Server 2008, HP-UX, Red Hat Enterprise Linux AS & ES 5 SuSE Linux Enterprise Server 10.0, VMware ESX and ESXi 3.5.x*
Instructor notes
XCS 6.1 introduces volume reduction; very limited support within the OS’s. Supported on HP-UX and Windows Server 2008 with Dynamic Capacity Manager (DCM).
Storage Volume Growth (SVG) uses the Online Volume Growth wizard from HP StorageWorks Storage Virtual Replicator. Extendfs may be used on HP-UX without LVM, however this is not often the case for customer environments. Usually LVM or VxVM will be used.
Dynamic Capacity Management communicates with a Replication Solutions Manager host agent on the host to resize the file system, and also communicates with Command View EVA to resize the virtual disk, coordinating the interaction between the file system and the underlying virtual disk.
Manual file system resizing operations can be performed with various OS utilities or applications, including those listed above.
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

22. Managing HP Enterprise Virtual Array
Hosts and LUNs
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
Host — collection of FC HBAs (port WWNs) in same server
LUN — virtual disk presented to one or multiple hosts
Limits for hosts, connections, and LUNs
Maximum of 256 hosts
Maximum of 1,024 FC HBA connections
Maximum of 256 LUNs per FC HBA
Maximum of 8,192 presentations to hosts
Examples:
1 LUN presented to 1 host = 1 presentation
1 LUN presented to 256 hosts = 256 presentations
256 LUNs presented to 1 host each = 256 presentations
Instructor notes
Point the customer to the additional programs provided with the EVA4400 for demo of the setup of all of this via SmartStart EVA.
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

23. Managing HP Enterprise Virtual Array
Review Questions
Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
What is the minimum number of disks in a disk group? What is the maximum?
What is a protection level? What are the three choices you have for protection level when creating a disk group?
What is an enhanced disk group?
What is a vdisk? What is the maximum and minimum size for a vdisk?
What are the raid level (vraid) options available when creating a vdisk?
Instructor notes
Good idea to go over these questions since there is no lab for this module to encourage class participation and to see if students have an understanding of concepts discussed in this module
U4879S L.01 – © 2011 Hewlett-Packard Development Company, L.P.
U4879S L.01

24. Managing HP Enterprise Virtual Array
Basic Concepts and Terminology
U4879S L.01