ASM General Architecture

ASM Instance

SID=ant

ASM Instance

SID=bee

ASM Disks ASM Disks ASM Disks ASM Disks ASM Disks ASM Disks

ASM Diskgroup Tom ASM Diskgroup Dick ASM Diskgroup Harry

DB Instance

SID=sales

DB Instance

SID=test

DB Instance

SID=sales

DB Instance

SID=test

ASMB

ASMB

FG

FG FG

FG

Node2Node1 Group Servicestom=ant

dick=antharry=ant

Group Services tom=bee

dick=beeharry=bee

DBW0

DBW0DBW0

DBW0ASMB

RBAL RBAL

ARB0

ARBA

…ARB0

ARBA

…

ASMB

RBAL

RBAL RBAL

RBAL

Hierarchy

Database

Tablespace

Segment

Extent

Oracleblock

Data file

Physicalblock

ASMdisk group

ASM disk

ASM file

Allocation unitFile system

fileor

raw device

Failure Groups

Controller 1 Controller 2

Failure group 1 Failure group 2

Disk group A

Controller 3

Failure group 3

1 7 13

1 7 131 7 13

1 7 13

1 7 131 7 13

1 7 13

1 7 131 7 13

2

3

4

5

6

ASM Files

Database File

ASM file automatically spread inside disk group dgroupA

CREATE TABLESPACE sample DATAFILE '+dgroupA';

1234

1 2 3 4

Automatic ASM filecreation

RAC Software Storage Principles

Node1

Instance1

CRS home

Local storage

Oracle home

Noden

Instancen

CRS home

Local storage

Oracle home

…

Voting file

OCR file

Node1

Instance1

Local storage

Noden

Instancen

Local storage

…

Shared storage

Voting file

OCR file

CRS home

Oracle home

* *

Permits online patch upgrades

Software not a singlepoint of failure

Shared storage

OCR Architecture

Node1

OCR Cache

OCRprocess

Clientprocess

Node2

OCR Cache

OCRprocess

Node3

OCR Cache

OCRprocess

Clientprocess

OCRfile

Shared storage

RAC Database Storage Principles

Node1

Instance1

Shared storage

…Noden

Instancen

Onlineredo log filesfor instance1

Onlineredo log filesfor instancen

Data filesUndo tablespacefiles for

instance1

Undo tablespacefiles for

instancen

Flash recovery area files

Change tracking file

SPFILE

Control files

Temp files

Archivedlog files

Local storage

Archivedlog files

Local storage

Typical Cluster Stack with RAC

High-speed Interconnect

uDAPL or UDP Proprietary

Proprietary

Database shared storage

Interconnect

Servers

Oracle CRS

RACLinux, UNIX,

Windows

ASM

RACLinux

Windows

RAW

RACLinux

Windows

OCFS

RACAIX, HP-UX, Solaris

ASM

OS C/W

RAWOS CVM

CFS

RAC and Services

Up and down events notification engine

Listeners

RAC Instances

Application serverERP CRM

ERP ERP ERP ERP

CRM CRM CRM CRM

Sto

p/S

tar t

ser

vice

co

nn

ecti

on

s Mo

dify service to

instan

ce map

pin

g

Service connections

BackupPriorityAlertsTuning

Connection load balancing Service availability aware

CRS

Run time load balancingService location transparency

Restart failed components

Virtual IP Addresses and RAC

ERP=(DESCRIPTION= ((HOST=clusnode-1vip)) ((HOST=clusnode-2vip)) (SERVICE_NAME=ERP))

clnode-1

ERP=(DESCRIPTION= ((HOST=clusnode-1)) ((HOST=clusnode-2)) (SERVICE_NAME=ERP))

Timeoutwait

clnode-2

clnode-1 clnode-2

2

5

3

7

clnode-1vip

clnode-2vip

2

clnode-1vipclnode-2vip

3

4

7

Clients

14

6

15

6

Managing OCR: Overview

• The OCR content is critical to CRS.

• The OCR is automatically backed up physically:– Every four hours: CRS keeps the last three– At the end of every day: CRS keeps the last two– At the end of every week: CRS keeps the last two

• You can also:– Logically back up the OCR:

– Copy physical OCR backups

• Backups can be used for recovery purposes.

ocrconfig –showbackup ocrconfig –backuploc

ocrconfig -export

Recovering the OCR

1. Locate either a physical or a logical backup.

2. Restart all the nodes in single-user mode.

3. Restore the physical OCR backup or import the logical OCR backup:

4. Restart all the nodes in multiuser mode.

$ ocrconfig –restore \ > /app/oracle/product/10.1.0/crs_1/cdata/jfv_clus/day.ocr

$ ocrconfig –import /u01/logical_ocr/yesterday