Tag: 11gr2

VirtualBox command line start, stop and clone

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I find it convenient to install the oracle 11gr2 rdbms on Oracle Enterprise Linux 5, running as a virtual host using  VirtualBox  VM (That way i dont have to go through the pains of installing it on Ubuntu Linux, which is unsupported). I use this database on a daily basis for testing different oracle functionality.

I use the following virtualbox command line commands to start and stop the virtual machine. It is much faster that booting up the operating system and then starting oracle.

To stop the virtual machine(I have named the VM OEL7) , in its current state (With the oracle rdbms running)

$ VBoxManage  controlvm OEL7 savestate

To start it

$VBoxManage  startvm OEL7

It takes about 10 seconds to start it.

To make a clone of the Virtual Machine to a entirely new location. First shutdown the virtual machine and then

$VBoxManage clonevm OEL7 –options keepallmacs –name OEL7E –basefolder “/media/ExternalDrive/vimage2”

The –basefolder can be specified to be a new location on disk to create the new image.

11gr2 new awr reports for Real Application Clusters

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There are two new awr reports in 11gr2, which will be helpful to dba’s in Real Application Clusters Environments (RAC).

awrgrpt.sql

This is a cluster wide awr report, so you can see a lot of the information from all the nodes in the same section, and you can also see aggregated statistics from all the instances at the same time (You can see totals, averages and standard deviations).

awrgdrpt.sql

This is a cluster wide stats diff report (like you had awrddrpt.sql in 11gr1), comparing the stats differences between two different snapshot intervals, across all nodes in the cluster.

These are huge additions to the awr reports, that enable understanding the database performance in real application clusters environments.

11gR2 rac installation on 64 bit Linux step by step

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Yesterday i completed a 11g Release 2 real application clusters installation on 64 bit Oracle Enterprise Linux 4. The installation process is very similar to the 10g and 11gr1 installations, but much simpler. This was a two node cluster. There are some new concepts that are introduced in 11gR2 real application clusters. Below are some of my notes on 11gr2 new features for Rac and detailed steps that i followed to complete the installation.

Some new concepts in 11gR2 Rac


Oracle clusterware and ASM now are installed into the Same Oracle Home, and is now called the grid infrastructure install.

Raw devices are no longer supported for use for anything (Read oracle cluster registry, voting disk, asm disks), for new installs.

OCR and Voting disk can now be stored in ASM, or a certified cluster file system.

The redundancy level of your ASM diskgroup (That you choose to place voting disk on) determines the number of voting disks you can have.
You can place

  • Only One voting disk on an ASM diskgroup configured as external redundancy
  • Only Three voting disks on an ASM diskgroup configured as normal redundancy
  • Only Five voting disks on an ASM diskgroup configured as high redundancy


The contents of the voting disks are automatically backed up into the OCR

ACFS (Asm cluster file system) is only supported on Oracle Enterprise Linux 5 (And RHEL5), not on OEL4.

There is a new service called cluster time synchronization service that can keep the clocks on all the servers in the cluster synchronized (In case you dont have network time protocol (ntp) configured)

Single Client Access Name (SCAN), is a hostname in the DNS server that will resolve to 3 (or at least one) ip addresses in your public network. This hostname is to be used by client applications to connect to the database (As opposed to the vip hostnames you were using in 10g and 11gr1). SCAN provides location independence to the client connections connecting to the database. SCAN makes node additions and removals transparent to the client application (meaning you dont have to edit your tnsnames.ora entries every time you add or remove a node from the cluster).

Oracle Grid Naming Service (GNS), provides a mechanism to make the allocation and removal of VIP addresses a dynamic process (Using dynamic Ip addresses).

Intelligent Platform Management Interface (IPMI) integration, provides a new mechanism to fence server’s in the cluster, when the server is not responding.

The installer can now check the O/S requirements, report on the requirements that are not met, and give you fixup scripts to fix some of them (like setting kernel parameters).

The installer can also help you setup SSH between the cluster nodes.

There is a new deinstall utility that cleans up a existing or failed install.

And the list goes on an on.

I have broken up the installation process into 3 distinct documents, which can be found below

Installing 11gr2 grid infrastructure

Installing 11gr2 Real Application Clusters

Creating the 11gr2 Clustered database