Oracle RAC 12c Overview

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7/8/13 1 Copyright © 2012, Oracle and/or its affiliates. All rights reserved. 1 Oracle Real Application Clusters (RAC) 12c Markus Michalewicz Director of Product Management Oracle Real Application Clusters (RAC)

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Overview of the new Oracle Real Application Clusters 12c

Transcript of Oracle RAC 12c Overview

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Oracle Real Application Clusters (RAC) 12c Markus Michalewicz Director of Product Management Oracle Real Application Clusters (RAC)

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Safe Harbor Statement

The following is intended to outline our general product direction. It is intended for information purposes only, and may not be incorporated into any contract. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. The development, release, and timing of any features or functionality described for Oracle’s products remains at the sole discretion of Oracle.

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Agenda

§  Oracle RAC 12c Overview

§  Oracle RAC 12c for: –  Better Business Continuity and High Availability –  Cost-effective Workload Management –  Standardized Deployment and System Management

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The New Oracle RAC 12c Oracle RAC 12c provides:

1.  Better Business Continuity and High Availability (HA)

2.  Agility and Scalability

3.  Cost-effective Workload Management

Using

§  A standardized and improved deployment and management

§  A familiar and matured HA stack

Oracle Real Application Clusters (RAC)

Oracle Grid Infrastructure (GI):

Automatic Storage Management (ASM)

Oracle Clusterware (OCW)

Oracle Flex ASM

CRM  

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Standardize on Oracle RAC Different flavors, same management

Oracle GI DB A DB A

Oracle GI DB A DB A

DB A

Oracle RAC One Node Oracle RAC

High Availability

Scal

abili

ty

DB A

Oracle Restart

Oracle GI

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Standardize on Oracle RAC For better availability during maintenance operations

Oracle GI DB A DB A

DB A Oracle RAC

High Availability

Scal

abili

ty

Online (rolling) Patch and PSU Application Oracle GI DB A

DB A Oracle RAC One Node

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Standardize on Oracle RAC For all the flexibility you need

Oracle GI DB A DB A

Oracle GI DB A DB A

DB A

Oracle RAC One Node Oracle RAC

Flexibility

Scal

abili

ty

Re-configuration

to enable cluster

Online

upgrade

DB A

Oracle Restart

Oracle GI

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Standardize on Oracle RAC For better agility and consolidation

Oracle GI DB A DB A

Oracle RAC One Node

Oracle GI DB A DB A

DB A Oracle RAC

Consolidation

Agi

lity

DB A

Oracle Restart

Oracle GI

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Standardize on Oracle RAC and Oracle Multitenant The new standard for Oracle Database Consolidation

Oracle GI

Oracle RAC One Node

Consolidation

Agi

lity

Oracle GI

Oracle RAC

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Agenda

§  Oracle RAC 12c Overview

§  Oracle RAC 12c for: –  Better Business Continuity and High Availability –  Cost-effective Workload Management –  Standardized Deployment and System Management

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Application Continuity

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Dealing with Unknown Transaction State

CRM  

DB A DB A

DB A DB A

DB A

Pre-Oracle Database 12c § Database outages can cause

in-flight work to be lost, leaving users and applications in doubt

§ Often leads to –  User pains –  Duplicate submissions –  Rebooting mid-tiers –  Developer pains

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Tackling In-Flight Work for Unplanned Outages

§ Transaction Guard –  A Reliable protocol and API that returns the outcome of the last transaction

§ Application Continuity –  Safely attempts to replay in-flight work following outages and planned

operations.

Two New Features

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Application Continuity

CRM  

Masks Unplanned & Planned Outages

DB A DB A

DB A DB A

DB A

§  Replays in-flight (DML) work on recoverable errors

§  Masks many hardware, software, network, storage errors and outages when successful

§  Improves end-user experience and productivity without requiring custom application development ✔

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Application Continuity – Example

Application Servers

Database Servers

End User

A reliable replay of in flight work

Network Switches

User selects product from application and purchases it from the web checkout

User transaction arrives at application infrastructure. It makes it’s way through the application tiers and results in a database transaction being created

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Application Continuity – Example

Application Servers

Database Servers

End User

A reliable replay of in flight work

Network Switches The infrastructure hosting the database fails just before the transaction is committed to the database.

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Application Continuity – Example

Application Servers

Database Servers

End User

A reliable replay of in flight work

Network Switches

The jdbc driver detects the failure and checks with an available node in the cluster, using “Transaction Guard”, whether the transaction committed or needs to be replayed

If the transaction needs to be replayed, “Application Continuity” will submit all of the inflight work to a surviving node in the cluster and perform a commit. This all happens transparently to the application

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Application Continuity – Example

Application Servers

Database Servers

End User

A reliable replay of in flight work

Network Switches

The user receives confirmation that his order has been successfully completed.

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Oracle Automatic Storage Management (ASM) 12c

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The History of ASM

§  Pre-Oracle Database 10g storage management was provided by 3rd parties

§  Customer challenges –  Large databases required considerable storage management –  Best performance required raw storage –  NFS solutions, while simple, did not perform as well as raw –  For RAC, cluster file systems were not available

§  With Oracle 10g, ASM provided –  Simplicity of management, even better than NFS solutions –  Performance equal to raw disks

Why Oracle Developed ASM

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The History of ASM

§  Integrated volume manager and file system § Stripe and mirror files across disks in a ASM Disk Group § Automatic “Rebalance” § Built on the Oracle instance architecture § Manage storage as a global cluster “shared Disk Groups”

The Simple Idea

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ASM Overview Simplify the Stack

Server

Oracle Database

Operating System

Logical Volume Manager

File System

Server

Oracle Database

Operating System

ASM File System and Volume Management

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ASM Overview Oracle Database 11.2 or earlier

ASM Cluster Pool of Storage

Node2

Disk Group B Disk Group A

Node3 Node5 Node4

Shared Disk Groups Wide File Striping

One to One Mapping of ASM Instances to Servers

Node1

ASM Instance

Database Instance

ASM Disk

RAC Cluster

DBA DBA DBB DBB DBC DBB

ASM ASM ASM ASM ASM

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Oracle ASM 12c – Overview Oracle ASM 12c Standard Deployment

ASM Cluster Pool of Storage

Disk Group B Disk Group A Shared Disk Groups Wide File Striping

One to One Mapping of ASM Instances to Servers

ASM Instance

Database Instance

ASM Disk

RAC Cluster

Node4 Node3 Node2 Node1 Node5 ASM ASM ASM ASM ASM

ASM Instance

Database Instance

DBA DBA DBC DBB DBB DBB

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Introducing Oracle Flex ASM Removal of One to One Mapping and HA

ASM Cluster Pool of Storage

Disk Group B Disk Group A Shared Disk Groups Wide File Striping

Databases share ASM instances

ASM Instance

Database Instance

ASM Disk

RAC Cluster

Node5 Node4 Node3 Node2 Node1

Node5 runs as ASM Client to Node4

Node1 runs as ASM Client to Node2

Node1 runs as ASM Client to Node4

Node2 runs as ASM Client to Node3

ASM ASM ASM

ASM Instance

DBA DBA DBC DBB DBB DBB

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Flex ASM

§  In previous versions, ASM clients use OS-authentication to connect to ASM –  This works because ASM clients and servers are always on the same server

§  With Oracle Database 12c, ASM clients and ASM servers can be on different servers

–  A default configuration is created when the ASM cluster is configured

§  Benefits of providing a shared password file in ASM Disk Group

Remote Access

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Supporting Pre-Oracle 12c Databases Pre-Oracle 12c Databases require a local ASM instance

ASM Cluster Pool of Storage

Disk Group B Disk Group A Shared Disk Groups Wide File Striping

Databases share ASM instances

ASM Instance

Database Instance

ASM Disk

RAC Cluster

Node5 Node4 Node3 Node2 Node1 ASM ASM ASM

DBA DBA DBC

ASM ASM

11gDB

11gDB DBB DBB DBB

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Flex ASM

§  Increase maximum number of Disk Groups to 511 –  Previous limit was 63

§ Command for renaming ASM Disk § ASM instance Patch-level verification

–  Patch level verification is disabled during rolling patches

§ Replicated Physical Metadata –  Improves reliability –  Virtual Metadata has always been replicated with ASM mirroring

Other Flex ASM Features

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Small ASM Features – Big Difference Disk and disk group operations

Failure Group repair time

§  Similar to existing disk repair time

§  Default is 24 hours

§  Disk group attribute: failgroup_repair_time

Disk Resync §  Accepts power limit

§  Range 1 (least resources) to 1024 (most resources)

§  Checkpoints: failed operations restart at the last checkpoint

Fast Disk Replacement §  Efficient, atomic operation

§  No disk group reorganization required

Data Scrubbing §  Check for logical consistency

(and repair from mirror)

§  during rebalance.

§  areas on demand

§  Protects seldom-accessed data

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Better availability and performance

Priority rebalancing §  Optimized re-organization

§  Control files, log files rebalanced first

§  Lowers impact of secondary failure

Even Read §  Distributes read requests evenly across all disks

§  Data read sent to least loaded disk

§  Enabled by default. Transparent to apps.

§  Preferred Read (for stretch clusters) can still be enabled

Disk group content type §  Data, recovery, or system type

§  Improved placement algorithm for primary/secondary extents

§  Lowers impact of multiple disk failures

I/O offloading to Exadata storage cells §  Rebalance uses fewer I/O resources

§  Faster rebalance

Small ASM Features – Big Difference

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Agenda

§  Oracle RAC 12c Overview

§  Oracle RAC 12c for: –  Better Business Continuity and High Availability –  Cost-effective Workload Management –  Standardized Deployment and System Management

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Policy-Managed Databases Highly available workload management

Policy Min Max Importance Online Retail 2 4 High Self Service 1 2 Low Free Pool Lowest

Allocate resources

§  As demand requires it

§  As the business requires it: §  Over the period of one day

§  As the system requires it: §  For automated management tasks

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Policy-Managed Databases Better High Availability for any cluster

Improve HA §  By choosing servers from the

least important server pool

§  Accommodating for double or multiple subsequent failures

§  For planned maintenance: §  Allocate backup servers in the cluster

1 2

Policy Min Max Importance Online Retail 2 4 High Self Service 1 2 Low Free Pool Lowest

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Policy-Managed Databases Customer quote: “Policy managed; It’s all about the workload”

Policy Logic defines:

§  Availability

§  Service Levels

§  Maint. windows

§  Performance

§  PCI requirements

§  Regional/business

§  Version

Policy Min Max Importance Americas 1 3 High EMEA 1 3 High

“Server pools are dynamically adjusted”

“Uniform services….don’t care where instances are or their name. All about capacity and workload”

“Instances are controlled by min/max combined with services. No more add/drop instance.”

“QoS is critical to our management”

Americas EMEA

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Policy-based Cluster Management Server Pools that understand and make a difference

•  Oracle RAC 12.1 •  Scales out easier than ever (addNode)

•  Actively utilizes differently sized servers

•  Server Pool management has been improved to understand server differences in the cluster: •  Server attributes are stored per server

•  Server Pools are set up using Server Categories

•  Servers are allocated to pools based on categories

•  Combine only test servers in one pool

•  Remove servers from test-pool preferably

•  Ensure a minimum size of servers per pool

Server Categories •  NAME •  ACL •  EXPRESSION •  …

Server Attributes •  NAME •  MEMORY_SIZE  •  CPU_COUNT •  CPU_CLOCK_RATE  •  CPU_HYPERTHREADING  •  CPU_EQUIVALENCY • …  

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What-If Command Evaluation Complex cluster management made predictable

•  Oracle RAC 12.1 What-If Command Evaluation

•  Helps to set up and validate policies

•  Helps to plan for downtime scenarios •  Analyze the impact beforehand

•  Ensure smooth cluster operations

•  What-If Command Evolution supports: •  Set Active Policy

•  Server Pool, server or resource modification

•  E.g. addition, relocation or removal

•  Special commands for failure evaluation

PROD

MAIL

Action: Move server

between pools

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What-If Command Evaluation How it works

[grid@LnxRAC12Srv1 bin]$ ./srvctl config srvpool ... Server pool name: mail Importance: 0, Min: 1, Max: 3 ... Candidate server names: Server pool name: prod Importance: 0, Min: 1, Max: 2 ...

The DBA view: >> srvctl relocate server -servers lnxrac12srv1 -serverpool mail -eval Database rac will be stopped on node lnxrac12srv1 Server lnxrac12srv1 will be moved from pool ora.prod to pool ora.mail

The cluster administrator view: >> crsctl eval relocate server lnxrac12srv1 -to ora.mail -f Stage Group 1: ------------------------------------------------------------------------------ Stage Number Required Action ------------------------------------------------------------------------------ 1 Y Server 'lnxrac12srv1' will be moved from pools [ora.prod] to pools [ora.mail] 2 Y Resource 'ora.rac.db' (1/1) will be in state [OFFLINE] ------------------------------------------------------------------------------

Action: Move server

between pools

PROD

MAIL

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Small Oracle RAC 12c Feature – Big Difference Optimized Flexibility and Agility

Support for IPv6 Based IP Addresses for Oracle RAC Client Connectivity

§  Cluster nodes can be configured to use either IPv4 or IPv6 based IP addresses or both

§  for the Virtual IPs (VIP) on the public network

§  more than one public network can be defined

Restricted Service Registration §  Restrict clients from accessing a database

registered with a Oracle Grid Infrastructure managed listener using various conditions

§  For example: on a per-subnet basis

Per-subnet (multiple) SCAN support §  Multiple SCANs can be configured per cluster

§  On a per-subnet basis

§  Subnets need to be distinguishable

Named User Support for Oracle RAC Services on Windows §  Oracle RAC supports running various

Oracle RAC services as different users.

§  This is a Windows-specific feature

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Agenda

§  Oracle RAC 12c Overview

§  Oracle RAC 12c for: –  Better Business Continuity and High Availability –  Cost-effective Workload Management –  Standardized Deployment and System Management

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Standardize on Oracle RAC and Oracle Multitenant The new standard for Oracle Database Consolidation

Oracle GI

Oracle RAC One Node

Consolidation

Agi

lity

Oracle GI

Oracle RAC

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Oracle RAC Support for Oracle Multitenant

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Oracle RAC support for Oracle Multitenant Start off with a Single Instance, non-CDB

Server

Database Instance

Services

Server

Database Instance

CRM North

CRM South Services CRM

Reporting

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Oracle RAC support for Oracle Multitenant Convert to a RAC Database, non-CDB

Node 1

RAC Instance 1

Services

Node 1

RAC Instance 1

CRM North

CRM South Services

Node 2

RAC Instance 2

CRM Reporting

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Oracle RAC support for Oracle Multitenant Convert to a CDB RAC Database

Node2

CDB Instance 2

Node1

CDB Instance 1

CDB

Services

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Expand Cluster to Support Flexible Consolidation Model Services

Single SGA per CDB Instance

Improved Agility With Changing Workloads

Node1

CDB Instance 1

Node2

CDB Instance 2

Multitenant Container Database (CDB)

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Services

Single SGA per CDB Instance

Expand Cluster to Support Flexible Consolidation Model

Node1

CDB Instance 1

Node2

CDB Instance 2

Node3

CDB Instance 3

Improved Agility With Changing Workloads

Multitenant Container Database (CDB)

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Oracle RAC and Virtualization

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Private Database Cloud Architectures Oracle Database 12c

Dedicated Databases

share servers and OS

Virtual Machines

share servers

Pluggable Databases

share servers, OS and database

Increasing Consolidation

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Virtualization – a Black Box Approach A simple solution without insight

Bare-Metal Server

DOM-0 Hypervisor Guest

Dom-0 Guest

Bare-Metal Server

DOM-0 Hypervisor

Dom-0 Guest Guest

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Live Migration = Moving a Black Box Live Migration moves a black box from one server to another

Bare-Metal Server

DOM-0 Hypervisor Guest

Dom-0 Guest

Bare-Metal Server

DOM-0 Hypervisor

Dom-0 Guest Guest

Live Migration

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Virtual Machine HA = Restarting a Black Box Virtual Machine HA restarts / fails over a virtual machine on failure

Bare-Metal Server

DOM-0 Hypervisor Guest

Dom-0 Guest

Bare-Metal Server

DOM-0 Hypervisor

Dom-0 Guest Guest

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Virtual Machine HA = Restarting a Black Box But what if the application needs attention?

Bare-Metal Server

DOM-0 Hypervisor Guest

Dom-0 Guest

Bare-Metal Server

DOM-0 Hypervisor

Dom-0 Guest

DBA ?

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High Availability Requires Insight The Oracle RAC Stack provides the insight

Bare-Metal Server

DOM-0 Hypervisor Guest

Dom-0 Guest

Bare-Metal Server

DOM-0 Hypervisor

Dom-0 Guest Guest

DBC1 DBA1

+1

DBC2 DBA2

+1

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Oracle Flex Cluster

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Oracle Flex Cluster Flexibility and High Availability as demand requires it

§  Oracle Flex Cluster –  A new Oracle Clusterware based

High Availability clustering topology

§  Utilizing two types of cluster nodes: –  Hub nodes

§  Traditional nodes, tightly coupled via network and storage, used for running IO intensive workload

–  Leaf nodes

§  A new type of node that runs a lighter weight stack

§  Maintain their own failure and heartbeat settings

§  Do not require direct shared storage connectivity

§  Used for processing oriented (application) workload

–  Leaf nodes can be virtualized.

Hub Nodes

Leaf Nodes

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Oracle Flex Cluster The new standard for resource management in the cluster

DB A DB A

DB A DB B

DB B

Hub Nodes

Leaf Nodes

§  Oracle Flex Cluster: –  The new standard for flexible

resource management in the cluster §  Use it as demand requires it

§  Inherits all Flex ASM HA capabilities

§  Enables policy-managed clusters.

–  Efficient High Availability and resource management across tiers

§  Lightweight cluster stack on leaf nodes

–  Benefit from virtualization and physical deployments in one cluster

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Oracle Flex Cluster Better HA clustering for all applications

DB A DB A

DB A DB B

DB B

§  Standardized management across applications –  Global resource allocation and dependencies

–  Oracle Bundled Agents (XAG) for application HA

§  www.oracle.com/goto/clusterware

Sta

rt

Stop

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