Virtual Storage Management for the Enterprise

Transcription

1 Virtual Storage Management for the Enterprise 18 May 2010 Dave Brown Technical Account Manager DataCore Software Corp 1

2 Overview Reduce storage management costs Reduce capital investments in storage Reduce power requirements Increase availability Non-disruptive scaling Increase disk / storage utilization. 2

3 The What, Why, Where & How What is storage virtualization? Why would you want to do it? Where (in your network) should you do it? Managing your virtualized storage environment, how much can one do, why you might want to oversubscribe and how fast is fast? Where do you learn more? How do you get started? What do I know about storage virtualization? 3

4 Virtualized storage history Monolithic Direct Attached storage The birth of the SAN Did utilization really improve? Credit to the IBM mainframe If you are virtualizing servers & desktops, why not storage? When you virtualize storage, where should you do it? Why? 4

5 What is Storage Virtualization? From the SNIA dictionary: Storage virtualization defined 1. [Storage System] The act of abstracting, hiding, or isolating the internal function of a storage (sub) system or service from applications, compute servers or general network resources for the purpose of enabling application and network independent management of storage or data. 2. [Storage System] The application of virtualization to storage services or devices for the purpose of aggregating, hiding complexity or adding new capabilities to lower level storage resources. 5

6 What is Storage Virtualization? What are we really talking about when referring to storage virtualization Block-level virtualization File-level virtualization Problems addressed Business value Sustainable advantage 6

7 Some Storage Virtualization Concepts Abstracting the disk array from the host; commonality in management Thin provisioning, why that can be good Thin provisioning with oversubscription, why that can be even better, or too much of a good thing? Storage pooling Quality of service 7

8 Why would you want to do it? Hard dollar cost savings, ability to unhook yourself from a given storage vendor Stop buying features over and over again Don t pay for capacity Heterogeneous copying of data from one vendors array to another Soft dollar cost savings, decreased management time setting up and changing the storage environment 8

9 Where should you do it? Host based Array based Network based (out of band, out of band but inspecting every frame, in band) Virtualization appliances 9

10 How much can a single Admin do? Very subjective answer, really an it depends. Ex. of 200TB/admin. SMI-S, CIM, WBEM are all meant to help address this but today s environment is still initially carving a given array and handing it to the virtualization solution The big gain is a common look to all the hosts, or a customized look dependent on the host s needs (e.g. vendor specific multipathing software and disk it likes to see) All on-line allocation and de-allocation, synchronous mirroring and async replication, full volume copy & pointer based snapshots, H/A data migration Just a couple mouse clicks to an up to date Visio diagram 10

11 Storage Performance How fast is fast? 11

12 How do you get more performance? Host Cached block (from Memory) ~2 μsec Moore s Law Processor speed doubles every 18 mos. Storage Network cache ~20 μsec 3-5 year development cycle for incremental improvement High-end Cached Storage Array Standalone JBOD (15K rpm disks) ~300 μsec >3500 μsec 12

13 Room A H/A Storage in a VM Load Balance, Migrate & Fail-over VMs Using Internal Drives Room B VM VM VM VM iscsi SAN over Ethernet LAN Mirroring 13

14 Turbo-charged Virtual Disk I/O Avg. Response (µs) DataCore L1 Cache <20 Array L2 Cache Disk Drive Poll for Input Output from Cache CPU Write Coalesce High-Speed Level 1 Caching CPU Pre-fetch CPU Cached Array Cached Array Un-cached Array CPU Disk Subsystems 14

15 Guessing on Allocation Leads to Waste Disk 1 Disk 2 Disk 3 Free Free Disk 1 Few Blocks Actually Written To Disk Free 3 Free Disk 2 Capacity consumed whether used or not! 15

16 Waste-Free Thin Provisioning Free V Disk 3 2TB Virtual Allocation: + 2.0TB + 2.0TB + 2.0TB 0 Free V Disk 2 2TB 6.0TB Actual = 0.4TB 0 Free V Disk 1 2TB 60% Free 0 Physical Disk Pool Time to add more Expand as Needed No Device Dependency 0 0.4TB 1TB 16

17 Thin Provisioning Space Reclamation Recover space from deleted files in virtual volumes 2TB Free V Disk 1 Space previously allocated to deleted file 0 2TB Free V Disk 1 Fill with zeroes 0 Release zero-filled space back to free pool 0 Physical Disk Pool 17

18 Real Thin Example: 250 GB Virtual Disk only occupies 20 GB 18

19 Availability: What s in your Data Center? 19

20 Is this really highly available? 20

21 Highly Available Mirrored Datasets Client 1 Virtual Disk Separate Chassis Different Location Independent Power Independent Cooling Separate UPS 4 2 Node A Active Synchronous Mirroring Partner Node B 3 5 Cache Cache 6 Mirror (P) Mirror (S) 21

22 Automatic Failover via Multipath I/O Virtual Disk Client Preferred Alternate Fail Retry Node A Offline 3 Partner Node B Cache Log Updates Cache 2 Out-of- Mirror Sync P Mirror S 22

23 Resynchronization of Mirrored Drives Client Alternate Virtual Disk Node A Rejoin Transmit changes since outage Partner Node B Cache Log Updates Cache Out-of- Mirror Sync P Mirror S 23

24 Resume Normal Operations Virtual Disk Client Preferred Alternate Off Node A Active Synchronous Mirroring Partner Node B Cache Cache Mirror P Mirror S 24

25 Track Health of High Availability Mirrors 25

26 N+1 Redundancy & Load Distribution A C B S S S P= Primary S= Secondary (Mirror) P 1 S P S P S 4 1 SANsymphony Nodes

27 Non-Disruptive Disk Upgrades Virtual disks remain active while contents are migrated to a different device Tier 1 Old New New Physical Storage Pool Tier 2 Tier 3 Retain or discard older device 27

28 Low-impact, Point-in-time Snapshots Earlier pointin-time Copy Empty original when contents Snapshot here on 1 st enabled write If unchanged, read from Source Active program Source Back-up Testing Analysis Recovery 4 Current image Only changed blocks take up space Source disk blocks 28

29 Roll Back To Image from Any Earlier Point CDP Active Synchronous Mirror Time-Stamped Updates Hours Days Weeks Cache Snapshot Dec 6 Nov Noon + = days Nov 9 6:31pm 29

30 Keep Remote Disaster Recovery Site Updated DR Site Destination Recovery Image Active Source Cache Central IT site Queued Updates IP Replicated Updates Snapshot Cache Asynchronous Copy 30

31 Low Cost Alternative: 1-to-Many DR DR Site x DR Site y VM VM VM VM VM VM HA VM VM Remote Replication DR Site z Thin pipes Central IT site Storage Virtualization VM VM 31

32 Advanced Site Recovery Central IT site Live Mapped (online) Mapped (offline) DR Live (P) DR Copy Sync Mirror Only to restore Kept current with DR site Live (S) 3 Transmit Queue 1 Internet WAN Transmit Queue DR (P) 2 Async Copy Sync Mirror Hourly Snapshots HA Optional DR (S) DR Site x 32

33 Where do you learn more? SNIA tutorials, either classroom or booklet based Storage Networking World classes Storage specific books InfoStor magazine TechTarget magazine / newsletter / mailing lists Network World storage specific mailing lists Byte & Switch 33

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37 How do you get started? 37 Attending this seminar Reading the just mentioned materials and attending storage specific conferences Talk with your peers that may be further along the storage path Who do you choose? Vendor agnostic, or one that has their own disk to sell first? One that s been in the business shipping a product longer than all the its competitors or one that gets in and out? Talk with a VAR of storage virtualization products See a product demonstration 37

38 The 3 rd dimension of virtualization Desktop Virtualization Server Virtualization Storage Virtualization 38

39 Truly heterogeneous architecture Performance High Availability Utilization Replication Snap Shot Security Data Migration 39