11gr2 rac/grid clusterware: best practices, pitfalls, and lessons learned presented during doug...

11gR2 RAC/Grid Clusterware: Best Practices, Pitfalls, and

Lessons LearnedPresented during DOUG meeting held on 10/21/2010 at Dallas, TX

Ramkumar Rajagopal

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Introduction

DBARAC is a specialty database consulting firm with expertise in a variety of industries based at Austin, Texas.Our people are experts in Oracle Real application clustered database focused solutions for managing large database systems.We provide proactive database management services including but not limited to In-house, on-shore DBA support , remote DB support, database maintenance and backup and recovery.Our DBA Experts provide specialized services in the areas of -

Root cause analysis Capacity planning Performance tuning, Database migration and consolidation Broad industry expertiseHigh-Availability RAC database specialistsEnd-to-end database support

11GR2 Grid clusterware

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IntroductionPresenter

• Senior Database Consultant DBARAC • Oracle Database/Applications DBA since 1995• Dell, JP Morgan Chase, Verizon • Presenter @ Oracle Open world 2007• Author Dell Power Solutions articles


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AGENDA

• Introduction• Node eviction issue in 10g• What is “11GR2 Grid Clusterware”?• The Challenges• What’s different today?• “We’ve seen this before, smart guy…”

• Architecture and Capacity Planning• Upgrade Paths• Pre-installation best practices• Grid Clusterware Installation• Clusterware Startup sequence• Post Install steps • RAC Database build steps• Summary• Q&A


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Why a node is evicted?

• Split brain condition• • IO fencing

• CRS keeps the lowest number node up

• Node eviction detection


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Root Causes of Node Eviction

Network heartbeat lost

Voting disk problems

cssd is not healthy

Oprocd

Hang check timer

cssd and oclsomon race to suicide


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11GR2 Grid Clusterware Improvements

• Node eviction algorithm is enhanced

• Prevent a split-brain problem without rebooting the node

• Oracle High Availability Services Daemon

• Will still reboot in some cases

• Faster relocation of services on node failure in 11GR2

11GR2 Grid Clusterware

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9i/10g RAC Scenario

• Several separate versions of databases

• Several servers

• Space/resource issues

• Lesser resources

• Provisioning takes time


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Top concerns

• How many are using 11GR2 Grid clusterware?• Do you have more than one mission-critical databases

within single RAC cluster?• Can you allocate resources dynamically to handle peak

volumes of various application loads without downtime?

• Issues on using shared infrastructure• Will my database availability and recovery suffer ?• Will my database performance suffer ?• How to manage a large clustered environment to meet sla’s

for several applications?


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Why 11GR2 Grid CRS?

11GR2 Grid Clusterware is…

An Architecture

An IT Strategy– Clusterware & ASM storage deployed together – Many, many Oracle Database Instances– Drives Consolidation


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Challenges

• Skilled resources

• Meeting SLA’s

• End-to-end testing not possible

• Security Controls

• Capacity issues

• Higher short-term costs


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What’s different today?

• 11gR2 Grid CRS & ASM supports• 11GR2, 11GR1, 10gR1 and 10gR2 Single Instances•

• Powerful servers, 64Bit O/s

• Provisioning Framework to deploy

• Grid control


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11GR2 RAC DB Architecture Planning


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Capacity Planning

• What are the current requirements?

• What are the future growth requirements in the next 6-12months?

• To meet the demand – estimate the hardware requirements

• Data retention requirements

• Archiving and purging


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Capacity Planning metrics

• Database metrics for capacity planning• CPU & memory Utilization• I/O rates• Device utilization• Queue length• Storage utilization• Response time• Transaction rate• Network Packet loss• Network Bandwidth utilization


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Capacity Planning Strategy

• Examine existing engagement processes

• Examine existing capacity of servers/storage

• Define Hardware/database scalability

• Provisioning for adding capacity

• Integration testing

• Large clustered database

• SLA requirements•


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Comparison – 10g vs 11GR2

• Server consolidation

• Database consolidation

• Instance consolidation

• Storage consolidation


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AGENDA so far…

• Introduction• Node eviction issue in 10g• What is “11GR2 Grid clusterware”?• The Challenges• What’s different today?• “We’ve seen this before, smart guy…”

• Architecture and Capacity Planning• Upgrade Paths• Pre-installation best practices• Grid Clusterware Installation• Clusterware Startup sequence• Post Install steps • RAC Database build steps• Summary• Q&A


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• Upgrade Paths

• Out-of-place clusterware upgrade

• Rolling Upgrade

• Oracle 10gR2 - from 10.2.0.3

• Oracle 11gR1 - from 11.1.0.6


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Pre-installation best practices

• Network Requirements

• Cluster Hardware Requirements

• ASM Storage Requirements

• Verification Checks


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Pre-Installation best practices Network Configuration

• SCAN -Single Client Access Name • Failover - Faster relocation of services• Better Load balancing

• MTU package size of Network Adapter (NIC) • Forwarder, zone entries and reverse lookup • Ping tests • Two dedicated interconnect switches for redundant interconnects• Run cluvfy


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Pre install - Network - SCAN Configuration


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Pre Install Network - SCANVIP Troubleshooting

• SCAN Configuration:• $GRID_HOME/bin/srvctl config scan

• SCAN Listener Configuration:• $GRID_HOME/bin/srvctl config scan_listener• SCAN Listener Resource Status:

• $GRID_HOME/bin/crsctl stat res -w "TYPE = ora.scan_listener.type“

• $GRID_HOME/Listener.ora • Local and remote listener parameters


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Pre Install -Cluster Hardware requirements

• Os/kernel same on all servers in the cluster• Minimum 32 GB of RAM• Minimum Swap space 16GB • Minimum Grid Home free space 16GB• For each Oracle Home directory allocate 32 GB of space (for each

db -32GB)• Allocate adequate disk space for centralized backups • Allocate adequate storage for ASM diskgroups – DATA and FRA


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Cluster Hardware requirements continued…

Most cases: use UDP over 1 Gigabit Ethernet

For large databases - Infiniband/IP or 10 Gigabit Ethernet

Use OS Bonding/teaming to “virtualize” interconnect

Set UDP send/receive buffers high enough

Crossover cables are not supported


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Pre Install - ASM Storage configuration

• In 11gR2 ASM diskgroups are used • Grid infrastructure - OCR, Voting disk and ASMspfile. • Database - DATA and FRA.

• OCR and voting disks for Grid clusterware • OCR can now be stored in Automatic Storage Management (ASM).

• Add Second diskgroup for ocr using• - ./ocrconfig -add +DATA02

Change the compatibility of the new diskgroup to 11.2 as follows:ALTER DISKGROUP DATA02 SET ATTRIBUTE ‘COMPATIBILITY.ASM’=’11.2’; ALTER DISKGROUP DATA02 SET ATTRIBUTE ‘COMPATIBILITY.RDBMS’=’11.2’;


http://search.microsoft.com/default.asp?so=RECCNT&siteid=us/dev&p=1&nq=NEW&qu=ALTER&IntlSearch=&boolean=PHRASE&ig=01&i=09&i=99

http://search.microsoft.com/default.asp?so=RECCNT&siteid=us/dev&p=1&nq=NEW&qu=SET&IntlSearch=&boolean=PHRASE&ig=01&i=09&i=99

http://search.microsoft.com/default.asp?so=RECCNT&siteid=us/dev&p=1&nq=NEW&qu=ALTER&IntlSearch=&boolean=PHRASE&ig=01&i=09&i=99

http://search.microsoft.com/default.asp?so=RECCNT&siteid=us/dev&p=1&nq=NEW&qu=SET&IntlSearch=&boolean=PHRASE&ig=01&i=09&i=99

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AGENDA so far…

• Introduction• Node eviction issue in 10g• What is “11GR2 Grid clusterware”?• The Challenges• What’s different today?• “We’ve seen this before, smart guy…”

• Architecture and Capacity Planning• Upgrade Paths• Pre-installation best practices• Grid Clusterware Installation• Clusterware Startup sequence• Post Install steps • RAC Database build steps• Q&A


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Hardware/Software details

• 10gR2 architecture – 9 database servers, 25TB storage– Original Database Version: 10.2.0.5– Original RAC cluster version : 10.2.0.1– Original Operating System: Ret Hat Linux 5 As 64 Bit– Storage Type : ASM & RAW Storage

• 11gR2 Grid architecture – 4 database servers, 40TB storage– New Database Version: 11.2.0.2– New Grid Clusterware/ASM version: 11.2.0.2– New Operating System : Ret Hat Linux 5 As 64Bit– Data migration steps using Rman backup and restore and

data pump export dump files


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11GR2 Migration Steps

• Install 11gR2 Grid clusterware and Asm• Install 11gR2 database binaries for each

database separately • Create the 11gR2 database • Add additional ASM diskgroups• Install 11GR1/10gR2 database binaries • Create 11GR1/10gR2 databases • Take backup • Restore the data


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Pre-verification checks- cluvfy

• Before Clusterware installation • ./cluvfy stage -pre crsinst -n node1,node2, node3 –verbose

• Before Database installation• ./cluvfy stage -pre dbinst -n node1,node2, node3 -fixup -verbose


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11gR2 Grid Clusterware Installation – Step 1


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Step-2


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Step-3


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Step-4


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Step 5


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Step 6


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Step 7


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Step 8


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Step 8 cont..


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Step 9


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Step 9 cont...


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Step 10


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Step 11


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Step 11 cont..


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Step 12


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Step 12


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Step 13


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Step 14


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Runfixup.sh

• root> /tmp/runfixup.sh• Response file being used is

:/tmp/CVU_11.2.0.1.0_grid/fixup.response• Enable file being used is

:/tmp/CVU_11.2.0.1.0_grid/fixup.enable• Log file location: /tmp/CVU_11.2.0.1.0_grid/orarun.log• Setting Kernel Parameters...• fs.file-max = 327679• fs.file-max = 6815744• net.ipv4.ip_local_port_range = 9000 65500• net.core.wmem_max = 262144• net.core.wmem_max = 1048576• uid=501(grid)gid=502(oinstall)groups=502(oinstall),• 503(asmadmin),504(asmdba)


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Step 15


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Step 16


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Step 16 cont.…


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./orainstRoot.sh

Cd /home/oracle/oraInventory[root@oradb-grid1 oraInventory]# ./orainstRoot.shChanging permissions of /home/oracle/oraInventory.Adding read, write permissions for group.Removing read,write,execute permissions for world.

Changing groupname of /home/oracle/oraInventory to oinstall.The execution of the script is complete.[root@oradb-grid1 oraInventory]# cd /u01/app/oracle[root@oradb-grid1 oracle]# lsproduct scripts[root@oradb-grid1 oracle]# cd product[root@oradb-grid1 product]# ls11.2.0[root@oradb-grid1 product]# cd 11*[root@oradb-grid1 11.2.0]# lsgrid[root@oradb-grid1 11.2.0]# cd db*[root@oradb-grid1 grid]# ls root*root.sh[root@oradb-grid1 grid]# ./root.shRunning Oracle 11g root.sh script...


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./orainstRoot.sh

The following environment variables are set as: ORACLE_OWNER= oracle ORACLE_HOME= /u01/app/oracle/product/11.2.0/grid

Enter the full pathname of the local bin directory: [/usr/local/bin]:The file "dbhome" already exists in /usr/local/bin. Overwrite it? (y/n)[n]:The file "oraenv" already exists in /usr/local/bin. Overwrite it? (y/n)[n]:The file "coraenv" already exists in /usr/local/bin. Overwrite it? (y/n)[n]:Creating /etc/oratab file...Entries will be added to the /etc/oratab file as needed byDatabase Configuration Assistant when a database is createdFinished running generic part of root.sh script.Now product-specific root actions will be performed.2009-10-02 10:31:44: Parsing the host name2009-10-02 10:31:44: Checking for super user privileges2009-10-02 10:31:44: User has super user privilegesUsing configuration parameter file: /u01/app/oracle/product/11.2.0/grid/crs/install/crsconfig_paramsCreating trace directoryLOCAL ADD MODE


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./orainstRoot.sh

Creating OCR keys for user 'root', privgrp 'root'..Operation successful. root wallet root wallet cert root cert export peer wallet profile reader wallet pa wallet peer wallet keys pa wallet keys peer cert request pa cert request peer cert pa cert peer root cert TP profile reader root cert TP pa root cert TP peer pa cert TP pa peer cert TP profile reader pa cert TP profile reader peer cert TP peer user cert pa user certAdding daemon to inittab


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./orainstRoot.sh

CRS-4123: Oracle High Availability Services has been started.ohasd is startingCRS-2672: Attempting to start 'ora.gipcd' on 'oradb-grid1'CRS-2672: Attempting to start 'ora.mdnsd' on 'oradb-grid1'CRS-2676: Start of 'ora.gipcd' on 'oradb-grid1' succeededCRS-2676: Start of 'ora.mdnsd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.gpnpd' on 'oradb-grid1'CRS-2676: Start of 'ora.gpnpd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.cssdmonitor' on 'oradb-grid1'CRS-2676: Start of 'ora.cssdmonitor' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.cssd' on 'oradb-grid1'CRS-2672: Attempting to start 'ora.diskmon' on 'oradb-grid1'CRS-2676: Start of 'ora.diskmon' on 'oradb-grid1' succeededCRS-2676: Start of 'ora.cssd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.ctssd' on 'oradb-grid1'CRS-2676: Start of 'ora.ctssd' on 'oradb-grid1' succeeded

ASM created and started successfully.

DiskGroup DATA created successfully.


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./orainstRoot.sh

clscfg: -install mode specifiedSuccessfully accumulated necessary OCR keys.Creating OCR keys for user 'root', privgrp 'root'..Operation successful.CRS-2672: Attempting to start 'ora.crsd' on 'oradb-grid1'CRS-2676: Start of 'ora.crsd' on 'oradb-grid1' succeededCRS-4256: Updating the profileSuccessful addition of voting disk 659585bf3a834f39bf281fd47e9ed6db.Successful addition of voting disk 762177cd6f844f25bfc677fb681a02ab.Successful addition of voting disk 154c17a0de9c4ffdbff9a3b2f22b52f6.Successfully replaced voting disk group with +DATA.CRS-4256: Updating the profileCRS-4266: Voting file(s) successfully replaced## STATE File Universal Id File Name Disk group-- ----- ----------------- --------- --------- 1. ONLINE 659585bf3a834f39bf281fd47e9ed6db (/dev/oracleasm/disks/VOL1) [DATA] 2. ONLINE 762177cd6f844f25bfc677fb681a02ab (/dev/oracleasm/disks/VOL2) [DATA] 3. ONLINE 154c17a0de9c4ffdbff9a3b2f22b52f6 (/dev/oracleasm/disks/VOL4) [DATA]Located 3 voting disk(s).


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./orainstRoot.sh

CRS-2673: Attempting to stop 'ora.crsd' on 'oradb-grid1'CRS-2677: Stop of 'ora.crsd' on 'oradb-grid1' succeededCRS-2673: Attempting to stop 'ora.asm' on 'oradb-grid1'CRS-2677: Stop of 'ora.asm' on 'oradb-grid1' succeededCRS-2673: Attempting to stop 'ora.ctssd' on 'oradb-grid1'CRS-2677: Stop of 'ora.ctssd' on 'oradb-grid1' succeededCRS-2673: Attempting to stop 'ora.cssdmonitor' on 'oradb-grid1'CRS-2677: Stop of 'ora.cssdmonitor' on 'oradb-grid1' succeededCRS-2673: Attempting to stop 'ora.cssd' on 'oradb-grid1'CRS-2677: Stop of 'ora.cssd' on 'oradb-grid1' succeededCRS-2673: Attempting to stop 'ora.gpnpd' on 'oradb-grid1'CRS-2677: Stop of 'ora.gpnpd' on 'oradb-grid1' succeededCRS-2673: Attempting to stop 'ora.gipcd' on 'oradb-grid1'CRS-2677: Stop of 'ora.gipcd' on 'oradb-grid1' succeededCRS-2673: Attempting to stop 'ora.mdnsd' on 'oradb-grid1'CRS-2677: Stop of 'ora.mdnsd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.mdnsd' on 'oradb-grid1'CRS-2676: Start of 'ora.mdnsd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.gipcd' on 'oradb-grid1'CRS-2676: Start of 'ora.gipcd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.gpnpd' on 'oradb-grid1'CRS-2676: Start of 'ora.gpnpd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.cssdmonitor' on 'oradb-grid1'CRS-2676: Start of 'ora.cssdmonitor' on 'oradb-grid1' succeeded


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./orainstRoot.sh

CRS-2672: Attempting to start 'ora.cssd' on 'oradb-grid1'CRS-2672: Attempting to start 'ora.diskmon' on 'oradb-grid1'CRS-2676: Start of 'ora.diskmon' on 'oradb-grid1' succeededCRS-2676: Start of 'ora.cssd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.ctssd' on 'oradb-grid1'CRS-2676: Start of 'ora.ctssd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.asm' on 'oradb-grid1'CRS-2676: Start of 'ora.asm' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.crsd' on 'oradb-grid1'CRS-2676: Start of 'ora.crsd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.evmd' on 'oradb-grid1'CRS-2676: Start of 'ora.evmd' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.asm' on 'oradb-grid1'CRS-2676: Start of 'ora.asm' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.DATA.dg' on 'oradb-grid1'CRS-2676: Start of 'ora.DATA.dg' on 'oradb-grid1' succeededCRS-2672: Attempting to start 'ora.registry.acfs' on 'oradb-grid1'CRS-2676: Start of 'ora.registry.acfs' on 'oradb-grid1' succeeded


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./orainstRoot.sh

oradb-grid1 2009/10/02 10:37:08 /u01/app/oracle/product/11.2.0/grid/cdata/oradb-grid1/backup_20091002_103708.olrPreparing packages for installation...cvuqdisk-1.0.7-1Configure Oracle Grid Infrastructure for a Cluster ... succeededUpdating inventory properties for clusterwareStarting Oracle Universal Installer...

Checking swap space: must be greater than 500 MB. Actual 39997 MB PassedThe inventory pointer is located at /etc/oraInst.locThe inventory is located at /home/oracle/oraInventory'UpdateNodeList' was successful.

oradb-grid2 output :-

[root@oradb-grid2 oraInventory]# pwd/home/oracle/oraInventory[root@oradb-grid2 oraInventory]# ./orainstRoot.shChanging permissions of /home/oracle/oraInventory.


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Step 16


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Step 16 cont.…


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Grid CRS Startup sequence


OHASD

oraRootAgent oraAgent cssdAgent cssdMonitor

crsd ctssd Diskmon ACFS

mdnsd gipcd gpnpd evmd

crsdRootAgent

GCS VIP

ASM

crsdOraAgent

networkResource SCAN VIPs Node VIPs ACFS Reg

DB Resource SCAN Listener Services ONS

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Clusterware verification

Clusterware processes–$ ps -ef|grep -v grep |grep d.binoracle 9824 1 0 Jul14 ? 00:00:00 /u01/app/grid11gR2/bin/oclskd.bin root 22161 1 0 Jul13 ? 00:00:15 /u01/app/grid11gR2/bin/ohasd.bin reboot oracle 24161 1 0 Jul13 ? 00:00:00 /u01/app/grid11gR2/bin/mdnsd.bin oracle 24172 1 0 Jul13 ? 00:00:00 /u01/app/grid11gR2/bin/gipcd.bin oracle 24183 1 0 Jul13 ? 00:00:03 /u01/app/grid11gR2/bin/gpnpd.bin oracle 24257 1 0 Jul13 ? 00:01:26 /u01/app/grid11gR2/bin/ocssd.bin root 24309 1 0 Jul13 ? 00:00:06 /u01/app/grid11gR2/bin/octssd.bin root 24323 1 0 Jul13 ? 00:01:03 /u01/app/grid11gR2/bin/crsd.bin reboot root 24346 1 0 Jul13 ? 00:00:00 /u01/app/grid11gR2/bin/oclskd.binoracle 24374 1 0 Jul13 ? 00:00:03 /u01/app/grid11gR2/bin/evmd.bin


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Clusterware checks–$ crsctl check crs CRS-4638: Oracle High Availability Services is online CRS-4537: Cluster Ready Services is online CRS-4529: Cluster Synchronization Services is online CRS-4533: Event Manager is online $ crsctl check has CRS-4638: Oracle High Availability Services is online $ crsctl query crs activeversion Oracle Clusterware active version on the cluster is [11.2.0.2.0]


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Clusterware processes$ crsctl check cluster -all ************************************************************** rat-rm2-ipfix006: CRS-4537: Cluster Ready Services is online CRS-4529: Cluster Synchronization Services is online CRS-4533: Event Manager is online ************************************************************** rat-rm2-ipfix007: CRS-4537: Cluster Ready Services is online CRS-4529: Cluster Synchronization Services is online CRS-4533: Event Manager is online ************************************************************** rat-rm2-ipfix008: CRS-4537: Cluster Ready Services is online CRS-4529: Cluster Synchronization Services is online CRS-4533: Event Manager is online **************************************************************


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$ crsctl status resource -t NAME TARGET STATE SERVER STATE_DETAILS ------------------------------------------------ ora.DATA.dg ASM disk group (new resource) ONLINE ONLINE rat-rm2-ipfix006 ONLINE ONLINE rat-rm2-ipfix007 ONLINE ONLINE rat-rm2-ipfix008 ora.LISTENER.lsnr ONLINE ONLINE rat-rm2-ipfix006 ONLINE ONLINE rat-rm2-ipfix007 ONLINE ONLINE rat-rm2-ipfix008 ora.asm ONLINE ONLINE rat-rm2-ipfix006 StartedONLINE ONLINE rat-rm2-ipfix007 Started ONLINE ONLINE rat-rm2-ipfix008 Started ora.eons new resource ONLINE ONLINE rat-rm2-ipfix006 ONLINE ONLINE rat-rm2-ipfix007 ONLINE ONLINE rat-rm2-ipfix008 ora.gsd


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Post Install Steps

• One-off patch –unlock the Grid home first• # perl rootcrs.pl -unlock -crshome

/u01/app/11.2.0/grid• Download and Install the latest Patch Updates• Back Up the root.sh Script• Install Cluster Health Management• Install OS Watcher and RACDDT• Check the backups of OCR and voting disks• Lock the Grid home after patch installation


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Manageability

• Grid control

• Adding/dropping nodes

• Automatically discovers services

• Policy-based cluster management

• Automated Cluster Patching

• End to end management of the cluster


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flexibilityScalability & Flexibility

• Sever pools of hardware available

• Consolidation of hardware and storage

• Rapid provisioning of resources to add capacity where its required

• Improved utilization of resources

• Better ROI


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Summary

• Reduced Hardware• Improved availability –SLAs• Shorter Time to add additional server or storage• Higher Security• Data Sharing & visibility• Better application performance• Centralized backup and archive• Higher ROI – higher utilization• Manageability• Pride in Ownership, Eliminating the Assembly Line• Bottom line = reduce TCO!


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References

• 11gR2Oracle® Clusterware Administration and Deployment Guide• Metalink ID 1054902.1 for Network configuration• RAC Assurance Support Team: RAC Starter Kit and Best Practices

(Linux)• Metalink NOTE:887522.1 - 11gR2 Grid Infrastructure Single Client

Access Name • Metalink NOTE:946452.1 - DNS and DHCP Setup Example for Grid

Infrastructure GNS Metalink Pre 11.2 Database Issues in 11gR2 Grid Infrastructure

Environment [ID 948456.1]


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11GR2 Grid cluster

Q & AEmail @ [email protected]


11gr2 rac/grid clusterware: best practices, pitfalls, and lessons learned presented during doug...

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