Sunday, August 14, 2011

Oracle 11g Release 1 RAC On Linux Using NFS


Oracle 11g Release 1 RAC On Linux Using NFS

This article describes the installation of Oracle 11g release 1 (11.1) RAC on Linux (Oracle Enterprise Linux 5.0) using NFS to provide the shared storage.

  • Introduction
  • Download Software
  • Operating System Installation
  • Oracle Installation Prerequisites
  • Create Shared Disks
  • Install the Clusterware Software
  • Install the Database Software
  • Create a Database using the DBCA
  • TNS Configuration
  • Check the Status of the RAC
  • Direct NFS Client

Introduction

NFS is an abbreviation of Network File System, a platform independent technology created by Sun Microsystems that allows shared access to files stored on computers via an interface called the Virtual File System (VFS) that runs on top of TCP/IP. Computers that share files are considered NFS servers, while those that access shared files are considered NFS clients. An individual computer can be either an NFS server, a NFS client or both.

We can use NFS to provide shared storage for a RAC installation. In a production environment we would expect the NFS server to be a NAS, but for testing it can just as easily be another server, or even one of the RAC nodes itself.

To cut costs, this articles uses one of the RAC nodes as the source of the shared storage. Obviously, this means if that node goes down the whole database is lost, so it's not a sensible idea to do this if you are testing high availability. If you have access to a NAS or a third server you can easily use that for the shared storage, making the whole solution much more resilient. Whichever route you take, the fundamentals of the installation are the same.

This article was inspired by the blog postings of
Kevin Closson.


Download Software

Download the following software.


Operating System Installation

This article uses Oracle Enterprise Linux 5.0, but it will work equally well on CentOS 5 or Red Hat Enterprise Linux (RHEL) 5. A general pictorial guide to the operating system installation can be found here. More specifically, it should be a server installation with a minimum of 2G swap, firewall and secure Linux disabled. Oracle recommend a default server installation, but if you perform a custom installation include the following package groups:

  • GNOME Desktop Environment
  • Editors
  • Graphical Internet
  • Text-based Internet
  • Development Libraries
  • Development Tools
  • Server Configuration Tools
  • Administration Tools
  • Base
  • System Tools
  • X Window System

To be consistent with the rest of the article, the following information should be set during the installation:

RAC1:

  • hostname: rac1.localdomain
  • IP Address eth0: 192.168.2.101 (public address)
  • Default Gateway eth0: 192.168.2.1 (public address)
  • IP Address eth1: 192.168.0.101 (private address)
  • Default Gateway eth1: none

RAC2:

  • hostname: rac2.localdomain
  • IP Address eth0: 192.168.2.102 (public address)
  • Default Gateway eth0: 192.168.2.1 (public address)
  • IP Address eth1: 192.168.0.102 (private address)
  • Default Gateway eth1: none

You are free to change the IP addresses to suit your network, but remember to stay consistent with those adjustments throughout the rest of the article.

Once the basic installation is complete, install the following packages whilst logged in as the root user.

# From Enterprise Linux 5 Disk 1

cd /media/cdrom/Server

rpm -Uvh binutils-2.*

rpm -Uvh elfutils-libelf-0.*

rpm -Uvh glibc-2.*

rpm -Uvh glibc-common-2.*

rpm -Uvh libaio-0.*

rpm -Uvh libgcc-4.*

rpm -Uvh libstdc++-4.*

rpm -Uvh make-3.*

cd /

eject



# From Enterprise Linux 5 Disk 2

cd /media/cdrom/Server

rpm -Uvh compat-libstdc++-33*

rpm -Uvh elfutils-libelf-devel-*

rpm -Uvh glibc-headers*

rpm -Uvh glibc-devel-2.*

rpm -Uvh libgomp*

rpm -Uvh gcc-4.*

rpm -Uvh gcc-c++-4.*

rpm -Uvh libaio-devel-0.*

rpm -Uvh libstdc++-devel-4.*

rpm -Uvh unixODBC-2.*

rpm -Uvh unixODBC-devel-2.*

cd /

eject



# From Enterprise Linux 5 Disk 3

cd /media/cdrom/Server

rpm -Uvh sysstat-7.*

cd /

eject

Oracle Installation Prerequisites

Perform the following steps whilst logged into the RAC1 virtual machine as the root user.

The /etc/hosts file must contain the following information.

127.0.0.1       localhost.localdomain   localhost

# Public

192.168.2.101   rac1.localdomain        rac1

192.168.2.102   rac2.localdomain        rac2

#Private

192.168.0.101   rac1-priv.localdomain   rac1-priv

192.168.0.102   rac2-priv.localdomain   rac2-priv

#Virtual

192.168.2.111   rac1-vip.localdomain    rac1-vip

192.168.2.112   rac2-vip.localdomain    rac2-vip

#NAS

192.168.2.101   nas1.localdomain        nas1

Notice that the NAS1 entry is actually pointing to the RAC1 node. If you are using a real NAS or a third server to provide your shared storage put the correct IP address into the file.

Add the following lines to the /etc/sysctl.conf file.

kernel.shmmni = 4096

# semaphores: semmsl, semmns, semopm, semmni

kernel.sem = 250 32000 100 128

net.ipv4.ip_local_port_range = 1024 65000

net.core.rmem_default=4194304

net.core.rmem_max=4194304

net.core.wmem_default=262144

net.core.wmem_max=262144



# Additional and amended parameters suggested by Kevin Closson

#net.core.rmem_default = 524288

#net.core.wmem_default = 524288

#net.core.rmem_max = 16777216

#net.core.wmem_max = 16777216

net.ipv4.ipfrag_high_thresh=524288

net.ipv4.ipfrag_low_thresh=393216

net.ipv4.tcp_rmem=4096 524288 16777216

net.ipv4.tcp_wmem=4096 524288 16777216

net.ipv4.tcp_timestamps=0

net.ipv4.tcp_sack=0

net.ipv4.tcp_window_scaling=1

net.core.optmem_max=524287

net.core.netdev_max_backlog=2500

sunrpc.tcp_slot_table_entries=128

sunrpc.udp_slot_table_entries=128

net.ipv4.tcp_mem=16384 16384 16384

Run the following command to change the current kernel parameters.

/sbin/sysctl -p

Add the following lines to the /etc/security/limits.conf file.

oracle               soft    nproc   2047

oracle               hard    nproc   16384

oracle               soft    nofile  1024

oracle               hard    nofile  65536

Add the following line to the /etc/pam.d/login file, if it does not already exist.

session    required     /lib/security/pam_limits.so

session    required     pam_limits.so

Disable secure linux by editing the /etc/selinux/config file, making sure the SELINUX flag is set as follows.

SELINUX=disabled

Alternatively, this alteration can be done using the GUI tool (System > Administration > Security Level and Firewall). Click on the SELinux tab and disable the feature.

Create the new groups and users.

groupadd oinstall

groupadd dba

groupadd oper

groupadd asmadmin



useradd -u 500 -g oinstall -G dba,oper,asmadmin oracle

passwd oracle

Configure SSH on each node in the cluster. Log in as the "oracle" user and perform the following tasks on each node.

su - oracle

mkdir ~/.ssh

chmod 700 ~/.ssh

/usr/bin/ssh-keygen -t rsa # Accept the default settings.

The RSA public key is written to the ~/.ssh/id_rsa.pub file and the private key to the ~/.ssh/id_rsa file.

Log in as the "oracle" user on RAC1, generate an "authorized_keys" file on RAC1 and copy it to RAC2 using the following commands.

su - oracle

cd ~/.ssh

cat id_rsa.pub >> authorized_keys

scp authorized_keys rac2:/home/oracle/.ssh/

Next, log in as the "oracle" user on RAC2 and perform the following commands.

su - oracle

cd ~/.ssh

cat id_rsa.pub >> authorized_keys

scp authorized_keys rac1:/home/oracle/.ssh/

The "authorized_keys" file on both servers now contains the public keys generated on all RAC nodes.

To enable SSH user equivalency on the cluster member nodes issue the following commands on each node.

ssh rac1 date

ssh rac2 date

ssh rac1.localdomain date

ssh rac2.localdomain date

exec /usr/bin/ssh-agent $SHELL

/usr/bin/ssh-add

You should now be able to SSH and SCP between servers without entering passwords.

Login as the oracle user and add the following lines at the end of the .bash_profile file.

# Oracle Settings

TMP=/tmp; export TMP

TMPDIR=$TMP; export TMPDIR



ORACLE_HOSTNAME=rac1.localdomain; export ORACLE_HOSTNAME

ORACLE_BASE=/u01/app/oracle; export ORACLE_BASE

ORACLE_HOME=$ORACLE_BASE/product/11.1.0/db_1; export ORACLE_HOME

ORACLE_SID=RAC1; export ORACLE_SID

ORACLE_TERM=xterm; export ORACLE_TERM

PATH=/usr/sbin:$PATH; export PATH

PATH=$ORACLE_HOME/bin:$PATH; export PATH



LD_LIBRARY_PATH=$ORACLE_HOME/lib:/lib:/usr/lib; export LD_LIBRARY_PATH

CLASSPATH=$ORACLE_HOME/JRE:$ORACLE_HOME/jlib:$ORACLE_HOME/rdbms/jlib; export CLASSPATH



if [ $USER = "oracle" ]; then

  if [ $SHELL = "/bin/ksh" ]; then

    ulimit -p 16384

    ulimit -n 65536

  else

    ulimit -u 16384 -n 65536

  fi

fi

Remember to set the correct values for the ORACLE_SID and ORACLE_HOSTNAME on the second node.


Create Shared Disks

First we need to set up some NFS shares. In this case we will do this on the RAC1 node, but you can do the on a NAS or a third server if you have one available. On the RAC1 node create the following directories.

mkdir /shared_config

mkdir /shared_crs

mkdir /shared_home

mkdir /shared_data

Add the following lines to the /etc/exports file.

/shared_config               *(rw,sync,no_wdelay,insecure_locks,no_root_squash)

/shared_crs                  *(rw,sync,no_wdelay,insecure_locks,no_root_squash)

/shared_home                 *(rw,sync,no_wdelay,insecure_locks,no_root_squash)

/shared_data                 *(rw,sync,no_wdelay,insecure_locks,no_root_squash)

Run the following command to export the NFS shares.

chkconfig nfs on

service nfs restart

On both RAC1 and RAC2 create the directories in which the Oracle software will be installed.

mkdir -p /u01/app/crs/product/11.1.0/crs

mkdir -p /u01/app/oracle/product/11.1.0/db_1

mkdir -p /u01/oradata

mkdir -p /u01/shared_config

chown -R oracle:oinstall /u01/app /u01/app/oracle /u01/oradata /u01/shared_config

chmod -R 775 /u01/app /u01/app/oracle /u01/oradata /u01/shared_config

Add the following lines to the "/etc/fstab" file. The mount options are suggestions from Kevin Closson.

nas1:/shared_config /u01/shared_config  nfs  rw,bg,hard,nointr,tcp,vers=3,timeo=300,rsize=32768,wsize=32768,actimeo=0  0 0

nas1:/shared_crs    /u01/app/crs/product/11.1.0/crs  nfs  rw,bg,hard,nointr,tcp,vers=3,timeo=300,rsize=32768,wsize=32768,actimeo=0  0 0

nas1:/shared_home   /u01/app/oracle/product/11.1.0/db_1  nfs  rw,bg,hard,nointr,tcp,vers=3,timeo=300,rsize=32768,wsize=32768,actimeo=0  0 0

nas1:/shared_data   /u01/oradata  nfs  rw,bg,hard,nointr,tcp,vers=3,timeo=300,rsize=32768,wsize=32768,actimeo=0  0 0

Mount the NFS shares on both servers.

mount /u01/shared_config

mount /u01/app/crs/product/11.1.0/crs

mount /u01/app/oracle/product/11.1.0/db_1

mount /u01/oradata

Create the shared OCR Configuration and Voting Disk files.

touch /u01/shared_config/ocr_configuration

touch /u01/shared_config/voting_disk

Make sure the permissions on the shared directories are correct.

chown -R oracle:oinstall /u01/shared_config

chown -R oracle:oinstall /u01/app/crs/product/11.1.0/crs

chown -R oracle:oinstall /u01/app/oracle/product/11.1.0/db_1

chown -R oracle:oinstall /u01/oradata

Before installing the clusterware, check the prerequisites have been met using the "runcluvfy.sh" utility in the clusterware root directory.

/mountpoint/clusterware/runcluvfy.sh stage -pre crsinst -n rac1,rac2 -verbose

If you get any failures be sure to correct them before proceeding.


Install the Clusterware Software

Unzip the clusterware and database software.

unzip linux_11gR1_clusterware.zip

unzip linux_11gR1_database.zip

Login to RAC1 as the oracle user and start the Oracle installer.

cd clusterware

./runInstaller

On the "Welcome" screen, click the "Next" button.



Accept the default inventory location by clicking the "Next" button.



Enter the appropriate name and path for the Oracle Home and click the "Next" button.



Wait while the prerequisite checks are done. If you have any failures correct them and retry the tests before clicking the "Next" button.



The "Specify Cluster Configuration" screen shows only the RAC1 node in the cluster. Click the "Add" button to continue.



Enter the details for the RAC2 node and click the "OK" button.



Click the "Next" button to continue.



The "Specific Network Interface Usage" screen defines how each network interface will be used. Highlight the "eth0" interface and click the "Edit" button.



Set the "eht0" interface type to "Public" and click the "OK" button.



Leave the "eth1" interface as private and click the "Next" button.



Click the "External Redundancy" option, enter "/u01/shared_config/ocr_configuration" as the OCR Location and click the "Next" button. To have greater redundancy we would need to define another shared disk for an alternate location.



Click the "External Redundancy" option, enter "/u01/shared_config/voting_disk" as the Voting Disk Location and click the "Next" button. To have greater redundancy we would need to define another shared disk for an alternate location.



On the "Summary" screen, click the "Install" button to continue.



Wait while the installation takes place.



Once the install is complete, run the orainstRoot.sh and root.sh scripts on both nodes as directed on the following screen.



The output from the orainstRoot.sh file should look something like that listed below.

# cd /u01/app/oraInventory

# ./orainstRoot.sh

Changing permissions of /u01/app/oraInventory to 770.

Changing groupname of /u01/app/oraInventory to oinstall.

The execution of the script is complete

#

The output of the root.sh will vary a little depending on the node it is run on. The following text is the output from the RAC1 node.

# cd /u01/app/crs/product/11.1.0/crs

# ./root.sh

WARNING: directory '/u01/app/crs/product/11.1.0' is not owned by root

WARNING: directory '/u01/app/crs/product' is not owned by root

WARNING: directory '/u01/app/crs' is not owned by root

WARNING: directory '/u01/app' is not owned by root

Checking to see if Oracle CRS stack is already configured

/etc/oracle does not exist. Creating it now.



Setting the permissions on OCR backup directory

Setting up Network socket directories

Oracle Cluster Registry configuration upgraded successfully

The directory '/u01/app/crs/product/11.1.0' is not owned by root. Changing owner to root

The directory '/u01/app/crs/product' is not owned by root. Changing owner to root

The directory '/u01/app/crs' is not owned by root. Changing owner to root

The directory '/u01/app' is not owned by root. Changing owner to root

Successfully accumulated necessary OCR keys.

Using ports: CSS=49895 CRS=49896 EVMC=49898 and EVMR=49897.

node :

node 1: rac1 rac1-priv rac1

node 2: rac2 rac2-priv rac2

Creating OCR keys for user 'root', privgrp 'root'..

Operation successful.

Now formatting voting device: /u01/shared_config/voting_disk

Format of 1 voting devices complete.

Startup will be queued to init within 30 seconds.

Adding daemons to inittab

Expecting the CRS daemons to be up within 600 seconds.

Cluster Synchronization Services is active on these nodes.

        rac1

Cluster Synchronization Services is inactive on these nodes.

        rac2

Local node checking complete. Run root.sh on remaining nodes to start CRS daemons.

#

The output from the RAC2 node is listed below.

# /u01/app/crs/product/11.1.0/crs

# ./root.sh

WARNING: directory '/u01/app/crs/product/11.1.0' is not owned by root

WARNING: directory '/u01/app/crs/product' is not owned by root

WARNING: directory '/u01/app/crs' is not owned by root

WARNING: directory '/u01/app' is not owned by root

Checking to see if Oracle CRS stack is already configured

/etc/oracle does not exist. Creating it now.



Setting the permissions on OCR backup directory

Setting up Network socket directories

Oracle Cluster Registry configuration upgraded successfully

The directory '/u01/app/crs/product/11.1.0' is not owned by root. Changing owner to root

The directory '/u01/app/crs/product' is not owned by root. Changing owner to root

The directory '/u01/app/crs' is not owned by root. Changing owner to root

The directory '/u01/app' is not owned by root. Changing owner to root

clscfg: EXISTING configuration version 4 detected.

clscfg: version 4 is 11 Release 1.

Successfully accumulated necessary OCR keys.

Using ports: CSS=49895 CRS=49896 EVMC=49898 and EVMR=49897.

node :

node 1: rac1 rac1-priv rac1

node 2: rac2 rac2-priv rac2

clscfg: Arguments check out successfully.



NO KEYS WERE WRITTEN. Supply -force parameter to override.

-force is destructive and will destroy any previous cluster

configuration.

Oracle Cluster Registry for cluster has already been initialized

Startup will be queued to init within 30 seconds.

Adding daemons to inittab

Expecting the CRS daemons to be up within 600 seconds.

Cluster Synchronization Services is active on these nodes.

        rac1

        rac2

Cluster Synchronization Services is active on all the nodes.

Waiting for the Oracle CRSD and EVMD to start

Waiting for the Oracle CRSD and EVMD to start

Oracle CRS stack installed and running under init(1M)

Running vipca(silent) for configuring nodeapps



Creating VIP application resource on (2) nodes...

Creating GSD application resource on (2) nodes...

Creating ONS application resource on (2) nodes...

Starting VIP application resource on (2) nodes...

Starting GSD application resource on (2) nodes...

Starting ONS application resource on (2) nodes...





Done.

#

Here you can see that some of the configuration steps are omitted as they were done by the first node. In addition, the final part of the script ran the Virtual IP Configuration Assistant (VIPCA) in silent mode.

You should now return to the "Execute Configuration Scripts" screen on RAC1 and click the "OK" button.



Wait for the configuration assistants to complete.



When the installation is complete, click the "Exit" button to leave the installer.



The clusterware installation is now complete.


Install the Database Software

Login to RAC1 as the oracle user and start the Oracle installer.

cd database

./runInstaller

On the "Welcome" screen, click the "Next" button.



Select the "Enterprise Edition" option and click the "Next" button.



Enter the name and path for the Oracle Home and click the "Next" button.



Select the "Cluster Install" option and make sure both RAC nodes are selected, the click the "Next" button.



Wait while the prerequisite checks are done. If you have any failures correct them and retry the tests before clicking the "Next" button.



Select the "Install Software only" option, then click the "Next" button.



On the "Summary" screen, click the "Install" button to continue.



Wait while the database software installs.



Execute the "root.sh" scripts on both nodes, as instructed on the "Execute Configuration scripts" screen, then click the "OK" button.



When the installation is complete, click the "Exit" button to leave the installer.





Create a Database using the DBCA

Login to RAC1 as the oracle user and start the Database Configuration Assistant.

dbca

On the "Welcome" screen, select the "Oracle Real Application Clusters database" option and click the "Next" button.



Select the "Create a Database" option and click the "Next" button.



Highlight both RAC nodes and click the "Next" button.



Select the "Custom Database" option and click the "Next" button.



Enter the values "RAC.WORLD" and "RAC" for the Global Database Name and SID Prefix respectively, then click the "Next" button.



Accept the management options by clicking the "Next" button. If you are attempting the installation on a server with limited memory, you may prefer not to configure Enterprise Manager at this time.



Enter database passwords then click the "Next" button.



Select the "Cluster File System" option, then click the "Next" button.



Select the "Use Oracle-Managed Files" option and enter "/u01/oradata/" as the database location, then click the "Next" button.



Check the "Specify Flash Recovery Area" option and and enter "/u01/oradata/" as the location, then click the "Next" button. Note.I wouldn't normally expect to see the flash recovery area and datafiles in the same location, but this is only a test.



Uncheck all but the "Enterprise Manager Repository" option, then click the "Standard Database Components..." button.



Uncheck all but the "Oracle JVM" and "Oracle XML DB" options, then click the "OK" button, followed by the "Next" button on the previous screen. If you are attempting the installation on a server with limited memory, you may prefer not to install the JVM at this time.



Accept the "Typical" memory management option by clicking the "Next" button.



Accept the 11g enhanced security settings by clicking the "Next" button.



Accept the automatic maintenance tasks by clicking the "Next" button.



Accept the database storage settings by clicking the "Next" button.



Accept the database creation options by clicking the "Finish" button.



Accept the summary information by clicking the "OK" button.



Wait while the database is created.



When prompted, click the "Yes" button to configure the listeners with the default settings.



Once the database creation is complete you are presented with the following screen. Make a note of the information on the screen and click the "Exit" button.



The RAC database creation is now complete.


TNS Configuration

Once the installation is complete, the "$ORACLE_HOME/network/admin/listener.ora" file in the shared $ORACLE_HOME will contain the following entries.

# listener.ora Network Configuration File: /u01/app/oracle/product/11.1.0/db_1/network/admin/listener.ora

# Generated by Oracle configuration tools.



LISTENER_RAC2 =

  (DESCRIPTION_LIST =

    (DESCRIPTION =

      (ADDRESS_LIST =

        (ADDRESS = (PROTOCOL = TCP)(HOST = rac2-vip)(PORT = 1521)(IP = FIRST))

      )

      (ADDRESS_LIST =

        (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.2.102)(PORT = 1521)(IP = FIRST))

      )

      (ADDRESS_LIST =

        (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC))

      )

    )

  )



LISTENER_RAC1 =

  (DESCRIPTION_LIST =

    (DESCRIPTION =

      (ADDRESS_LIST =

        (ADDRESS = (PROTOCOL = TCP)(HOST = rac1-vip)(PORT = 1521)(IP = FIRST))

      )

      (ADDRESS_LIST =

        (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.2.101)(PORT = 1521)(IP = FIRST))

      )

      (ADDRESS_LIST =

        (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC))

      )

    )

  )

The shared "$ORACLE_HOME/network/admin/tnsnames.ora" file will contain the following entries.

# tnsnames.ora Network Configuration File: /u01/app/oracle/product/11.1.0/db_1/network/admin/tnsnames.ora

# Generated by Oracle configuration tools.



RAC =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac2-vip)(PORT = 1521))

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac1-vip)(PORT = 1521))

    (LOAD_BALANCE = yes)

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = RAC.WORLD)

    )

  )



LISTENERS_RAC =

  (ADDRESS_LIST =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac2-vip)(PORT = 1521))

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac1-vip)(PORT = 1521))

  )



RAC2 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac2-vip)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = RAC.WORLD)

      (INSTANCE_NAME = RAC2)

    )

  )



RAC1 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac1-vip)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = RAC.WORLD)

      (INSTANCE_NAME = RAC1)

    )

  )

This configuration allows direct connections to specific instance, or using a load balanced connection to the main service.

$ sqlplus / as sysdba



SQL*Plus: Release 11.1.0.6.0 - Production on Tue Aug 14 19:16:47 2007



Copyright (c) 1982, 2007, Oracle.  All rights reserved.





Connected to:

Oracle Database 11g Enterprise Edition Release 11.1.0.6.0 - Production

With the Partitioning, Real Application Clusters, OLAP, Data Mining

and Real Application Testing options



SQL> CONN sys/password@rac1 AS SYSDBA

Connected.

SQL> SELECT instance_name, host_name FROM v$instance;



INSTANCE_NAME     HOST_NAME

----------------  ----------------------------------------------------------------

RAC1              rac1.lynx.co.uk



SQL> CONN sys/password@rac2 AS SYSDBA

Connected.

SQL> SELECT instance_name, host_name FROM v$instance;



INSTANCE_NAME     HOST_NAME

----------------  ----------------------------------------------------------------

RAC2              rac2.lynx.co.uk



SQL> CONN sys/password@rac AS SYSDBA

Connected.

SQL> SELECT instance_name, host_name FROM v$instance;



INSTANCE_NAME     HOST_NAME

----------------  ----------------------------------------------------------------

RAC1              rac1.lynx.co.uk



SQL>

Check the Status of the RAC

There are several ways to check the status of the RAC. The srvctl utility shows the current configuration and status of the RAC database.

$ srvctl config database -d RAC

rac1 RAC1 /u01/app/oracle/product/11.1.0/db_1

rac2 RAC2 /u01/app/oracle/product/11.1.0/db_1

$



$ srvctl status database -d RAC

Instance RAC1 is running on node rac1

Instance RAC2 is running on node rac2

$

The V$ACTIVE_INSTANCES view can also display the current status of the instances.

$ sqlplus / as sysdba



SQL*Plus: Release 11.1.0.6.0 - Production on Tue Aug 14 19:21:37 2007



Copyright (c) 1982, 2007, Oracle.  All rights reserved.





Connected to:

Oracle Database 11g Enterprise Edition Release 11.1.0.6.0 - Production

With the Partitioning, Real Application Clusters, OLAP, Data Mining

and Real Application Testing options



SQL> SELECT * FROM v$active_instances;



INST_NUMBER INST_NAME

----------- ------------------------------------------------------------

          1 rac1.lynx.co.uk:RAC1

          2 rac2.lynx.co.uk:RAC2



SQL>

Finally, the GV$ allow you to display global information for the whole RAC.

SQL> SELECT inst_id, username, sid, serial# FROM gv$session WHERE username IS NOT NULL;



   INST_ID USERNAME                              SID    SERIAL#

---------- ------------------------------ ---------- ----------

         2 SYS                                   116        841

         2 SYSMAN                                118         78

         2 SYS                                   119       1992

         2 SYSMAN                                121          1

         2 SYSMAN                                122         29

         2 SYS                                   123          2

         2 SYSMAN                                124         50

         2 DBSNMP                                129          1

         2 DBSNMP                                130          6

         2 DBSNMP                                134          1

         2 SYSMAN                                145         53



   INST_ID USERNAME                              SID    SERIAL#

---------- ------------------------------ ---------- ----------

         2 SYS                                   170         14

         1 SYSMAN                                117        144

         1 SYSMAN                                118        186

         1 SYSMAN                                119         31

         1 SYS                                   121          3

         1 SYSMAN                                122        162

         1 SYSMAN                                123         99

         1 DBSNMP                                124          3

         1 SYS                                   125          2

         1 SYS                                   126         19

         1 SYS                                   127        291



   INST_ID USERNAME                              SID    SERIAL#

---------- ------------------------------ ---------- ----------

         1 DBSNMP                                131         61

         1 SYS                                   170         17



24 rows selected.



SQL>

If you have configured Enterprise Manager, it can be used to view the configuration and current status of the database using a URL like "https://rac1.localdomain:1158/em".




Direct NFS Client

For improved NFS performance, Oracle recommend using the Direct NFS Client shipped with Oracle 11g. The direct NFS client looks for NFS details in the following locations:

  1. $ORACLE_HOME/dbs/oranfstab
  2. /etc/oranfstab
  3. /etc/mtab

Since we already have our NFS mount point details in the "/etc/fstab", and therefore the "/etc/mtab" file also, there is no need to configure any extra connection details.

For the client to work we need to switch the libodm11.so library for the libnfsodm11.so library, as shown below.

srvctl stop database -d RAC



cd $ORACLE_HOME/lib

mv libodm11.so libodm11.so_stub

ln -s libnfsodm11.so libodm11.so



srvctl start database -d RAC

With the configuration complete, you can see the direct NFS client usage via the following views:

  • v$dnfs_servers
  • v$dnfs_files
  • v$dnfs_channels
  • v$dnfs_stats

For example:

SQL> SELECT svrname, dirname FROM v$dnfs_servers;



SVRNAME        DIRNAME

-------------  -----------------

nas1           /shared_data



SQL>

The Direct NFS Client supports direct I/O and asynchronous I/O by default.

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