Transcript R_MOD_13-VNX_Snapshot
VNX Snapshot
Upon completion of this module, you should be able to: • Describe VNX Snapshot operations • Manage VNX Snapshot and Sessions Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 1
VNX Snapshot
Lesson 1: VNX Snapshots: Theory and Operation During this lesson the following topics are covered: • Purpose of VNX Snapshots • • VNX Snapshots requirements VNX Snapshots managed objects • VNX Snapshots theory of operations Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 2
VNX Snapshots
• VNX Snapshots – virtual point-in-time copy of a LUN Allows to create snapshots of pool-based LUNs Use pointer-based replication and Relocate on First Write (ROW) technology Make use of the source LUN’s parent Pool to store original data Have three managed objects: Snapshot, Snapshot Mount Point, Consistency Group • VNX Snapshots are managed by Unisphere Navisphere Secure CLI SnapCLI VNX Snapshot 3 Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshots Requirements
Hardware
Environment
Storage System Software Management Software Operating Systems
System Requirements
VNX Storage System Two or more Servers (if the VNX Snapshots snap is to be accessed by a host), each attached to the VNX that will run VNX Snapshots VNX Operating Environment for Block Release 32 VNX Snapshot enabler Unisphere UI Navisphere Secure CLI SnapCLI HP-UX IBM AIX Linux Solaris Windows Server Refer to EMC Support Matrix for a complete list VNX Snapshot 4 Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshots Managed Objects
• Primary LUN Pool LUN from which the snapshot is taken • Snapshot Point-in-time copy of a LUN • Snapshot Mount Point An object that is exposed to the host through a storage group • Consistency Group Persistent grouping of primary LUNs or Mount Points Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 5
VNX Snapshots Characteristics
Primary LUN 2:00 pm Snapshot 4:00 pm Snapshot 6:00 pm Snapshot Dev Snapshot Patch 1 Snapshot Patch 2 Snapshot • Scalability 256 snapshots per LUN Thin provisioned copies Lower write performance impact • Functionality Snapshot of a Snapshot RecoverPoint support Clone support • Consistency Groups VNX Snapshot 6 Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot Mount Points
• A Snapshot Mount Point is a container that holds SCSI attributes Behaves like a LUN of the same size as the Primary LUN Added as a member LUN in the secondary host Storage Group • A VNX Snapshot is attached to a Snapshot Mount Point (SMP) in order to allow host access to the replica data • VNX Snapshots are easily switched on one SMP No SCSI rescan is required on the host • Must have an attached Snapshot for data to be host-visible Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 7
VNX Snapshot Consistency Group
• • • A group of Primary LUNs or VNX Snapshot Mount Points Snapshots can be made of the entire Group Primary LUNs or VNX SMPs can be added to the Group Snapshots may have more or fewer members as a result Snapshots being restored must have the same members as the Group • • Does not require application I/O to be stopped Related terms VNX Snapshot Set a Snapshot of a Consistency Group VNX Snapshot Family – a group of Snapshots of the same LUN VNX Snapshot 8 Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView and VNX Snapshot Terminology Comparison
VNX Snapshot Term SnapView Term Definition
Snapshot Session Point in time copy Restore Attach Detach Consistency Group Snapshot Family Primary LUN Snapshot Mount Point Rollback Activate Deactivate n/a n/a Source LUN Snapshot [LUN] Restore primary LUN to point in time copy Make the point in time copy accessible to a host Remove the point in time copy from the host Persistent grouping of primary LUNs or Mount Points Pool LUN, all of its associated mount points and all of their snapshots Pool LUN that can be used by VNX Snapshots LUN that host uses to access the snapshot data VNX Snapshot 9 Copyright © 2014 EMC Corporation. All Rights Reserved.
Snapshot Technology Comparison: Source LUN Writes
Copy on first write
Copyright © 2014 EMC Corporation. All Rights Reserved.
Redirect on write
VNX Snapshot 10
Snapshot Technology Comparison: Snapshot Reads
Read from two places
Copyright © 2014 EMC Corporation. All Rights Reserved.
Read from a single place
VNX Snapshot 11
VNX Snapshot Operations
• • • • • • • • Create a Snapshot Create a Snapshot Mount Point (SMP) Attach a Snapshot Copy a Snapshot Snap a Snapshot Mount Point (Cascading Snapshots) Detach a Snapshot Mount Point Destroy a Snapshot Attach a Consistency Snapshot Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 12
Create a VNX Snapshot
Primary LUN Lun_20 Snap 1 (R/O)
Creation time:
8pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 2 (R/O)
Creation time:
9pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 1 Snap 2
Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 13
Create a VNX Snapshot Mount Point (SMP)
Primary LUN Lun_20 Snap 1 (R/O)
Creation time:
8pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 2 (R/O)
Creation time:
9pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 1 Snap 2 SMP1
Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 14
Attach a VNX Snapshot to a SMP
Primary LUN Lun_20 Snap 1 (R/O)
Creation time:
8pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 2 (R/W)
Creation time:
9pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
SMP1 Snap 1 Snap 2 SMP1
Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 15
Copy a VNX Snapshot (Snap of a Snap)
Primary LUN Lun_20 Snap 1 Snap 2 Snap 3
. . .
Snap 1 (R/W)
Creation time:
8pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 2 (R/W)
Creation time:
9pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
SMP1 Snap 2 (R/O)
Creation time:
8pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN: Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 16
Snap of a Snapshot Mount Point
. . .
Lun_20 Primary LUN Snap 1 Snap 1 (R/O)
Creation time:
8pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 2 Snap 2 (R/W)
Creation time:
9pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
SMP1 SMP1 Snap 2.1
Snap 1 (R/O)
Creation time:
10pm
Last modify time: Last modified by: Source LUN:
SMP1
Primary LUN:
LUN_20
Attached LUN:
Snap 2.2
Snap 2 (R/O)
Creation time:
11pm
Last modify time: Last modified by: Source LUN:
SMP1
Primary LUN:
LUN_20
Attached LUN:
SMP1
VNX Snapshot 17 Copyright © 2014 EMC Corporation. All Rights Reserved.
Detach a VNX Snapshot to a SMP
Primary LUN Snap 1 (R/O)
Creation time:
8pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 2 (R/W)
Creation time:
9pm
Last modify time:
11:47pm
Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
SMP1 Lun_20 Snap 1 Snap 2 X SMP1
Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 18
Destroy a VNX Snapshot
Primary LUN Lun_20 Snap 1 (R/O)
Creation time:
8pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 2 (R/O)
Creation time:
9pm
Last modify time: Last modified by: Source LUN:
LUN_20
Primary LUN:
LUN_20
Attached LUN:
Snap 1 SMP1
Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 19
Attach a Consistency Snapshot
Host 1 Lun_20 Lun_21 SMP LUN_20 SMP LUN_21 R/W CG Snap 1 CG1
Copyright © 2014 EMC Corporation. All Rights Reserved.
Host 2
VNX Snapshot 20
VNX Snapshot
Lesson 1: Summary During this lesson the following topics were covered: • Purpose of VNX Snapshots • • VNX Snapshots requirements VNX Snapshots managed objects • VNX Snapshots theory of operations Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 21
VNX Snapshot
Lesson 2: Managing VNX Snapshots During this lesson the following topics are covered: • Displaying VNX Snapshots • • VNX Snapshot expiration Cascading VNX Snapshots • Restoring VNX Snapshots Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 22
VNX Snapshot Management
Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshots 23
VNX Snapshot Properties
Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView Snapshots 24
VNX Snapshot Consistency Group Properties
Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView Snapshots 25
Storage Pool Properties - VNX Snapshots
Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView Snapshots 26
VNX Snapshot and SMP Creation
Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView Snapshots 27
VNX Snapshot Expiration
• Every VNX Snapshot may have an optional expiration date • Expired VNX Snapshots are destroyed at regular intervals • VNX array scans for expired snapshots once an hour • Set an expiration date only after Auto-Delete is disabled User is warned before Snapshots are deleted Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView Snapshots 28
Cascading VNX Snapshots
• VNX Snapshot of an attached Snapshot Mount Point
Not attached
Copyright © 2014 EMC Corporation. All Rights Reserved.
Attached
SnapView Snapshots 29
Restore
• • Use VNX Snapshot to restore a primary LUN or a SMP Data in the LUN is changed to match the data in the snapshot Does not change the “Restore Point” snapshot Return no the poin-in-time of the source data • • Used when recovering from data corruption LUN with state ‘Initializing’ while being restored Changes back to ‘Ready’ after the restore is complete • Restoring can change the LUN size If the source snapshot was taken before the primary LUN expansion or shrinking SnapView Snapshots 30 Copyright © 2014 EMC Corporation. All Rights Reserved.
Restore Considerations
• Restore with SnapView Snapshots and VNX Snapshots Restore a primary LUN from a VNX Snapshot All SnapView session must be manually stopped Restore a primary LUN from a SnapView Snapshot VNX Snapshots are unaffected • • Stop application access to the primary LUN Flush the buffers for the drive Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView Snapshots 31
Restoring a Primary LUN
Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView Snapshots 32
VNX Snapshot Configuration Wizard
Copyright © 2014 EMC Corporation. All Rights Reserved.
SnapView Snapshots 33
VNX Snapshot
Lesson 2: Summary During this lesson the following topics were covered: • VNX Snapshot Management • • VNX Snapshot properties VNX Snapshot expiration and restore Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 34
VNX Snapshot Summary
• • Key points covered in this module: VNX Snapshot provides a point-in-time virtual copy of pool based LUNs using ROW technology A Snapshot Mount Point is a container that holds SCSI attributes, behaves like a LUN, and is added to host Storage Group Copyright © 2014 EMC Corporation. All Rights Reserved.
VNX Snapshot 35