You are in trouble when more than 8 kernel options are enabled in oracle executable

A brief headsup for everyone responsible for maintaining kernel options in the oracle executable.

The environment where I discovered this is a 3 node racattack cluster with Oracle GI & RDBMS After enabling Unified auditing in my database I noticed that all of a sudden database startup started failing with an almost  unlimited amount of core dump files being generated.

SQL*Plus: Release (more...), failed and IB listener

So this customer has an Exadata quarter rack and they have an IB listener configured on both DB nodes (for DB connections from a multi-racked Exalogic system). We were adding a new DB node to this rack. So just followed the standard procedure of creating users, directories etc on the new node, setting up ssh equivalence and running All went fine but failed. Little looking into the logs revealed that it (more...)

Grid Infrastructure 12c installation fails because of 255 in the subnet ID

I was doing another GI cluster installation last month when I got really weird error.

While was running on the first node I got the following error:

2016/07/01 15:02:10 CLSRSC-343: Successfully started Oracle Clusterware stack
2016/07/01 15:02:23 CLSRSC-180: An error occurred while executing the command '/ocw/grid/bin/oifcfg setif -global eth0/ eth1/' (error code 1)
2016/07/01 15:02:24 CLSRSC-287: FirstNode configuration failed
Died at /ocw/grid/crs/install/  (more...)

SCAN Listener Crash After Applying July 2016 PSU

I ran in to a small issue while applying the July 2016 quarterly patch to a couple of Exadata racks last week.  The systems were running GI, previously with the January 2016 PSU.  The patches applied successfully, and we were beginning the process of running the post-patch scripts on the databases in the cluster.  This process involves manually starting the database in upgrade mode, and we saw a message in SQL*Plus that the (more...)

12cR1 RAC Installation on OEL7

To build Oracle Clusterware Database at Home, I believe , RAC ATTACK is the best place to learn. Its is a free curriculum and platform for hands-on learning labs related to Oracle RAC. While reviewing the article, I thought to perform 12cR1 RAC installation on OEL 7.2.

Attached is the document :- 12c_RAC_on_OEL7

The attached article is inspired by


Tim Hall’s article :- 

Deploying Oracle RAC (more...)

Using External Table on Windows RAC ACFS

One of my customer is using Oracle RAC ( on Windows 2012. This is might not be the most ideal setup I’ve ever seen, but it works and we’ll leave it by that.

One of the side effects of using Oracle RAC on Windows is that some of the basic things I am used to do when using RAC on Linux (for example) is behaving differently when it comes to windows. Here (more...)

UKOUG RDBMS and RAC-CIA Special Interest Groups

On Thursday 21st April, there is a dual UKOUG Database and RAC, Cloud, Infrastructure and Availability special interest group.

For the first time, this even is being held in the fabulous Northern city of Manchester!

There are a dozen interesting, career-assisting, educational talks from end users, Oracle employees and a number of well known Oracle ACE’s at all levels, including Carl Dudley, Jonathan Lewis, Phil Brown and myself.

I will be talking about how (more...)

When should you use Oracle RAC?

Over the past years we've worked on many Oracle projects, some with RAC, some without, some which intended to implement RAC and failed, and some which implemented poorly and ripped it out at the last minute. 

For those new to Oracle, RAC is the Real Application Cluster option for the database which lets you cluster the database servers. The main reason for using for RAC is that it brings resilience to a system, it (more...)

Killing Sessions

You have a session which is out of control. You decide to kill it. What options are available to you as a DBA?

Assuming you don’t have access to the O/S to be able to use O/S commands to kill the session (using kill -9 in Unix/Linux or orakill in windows to kill the thread within the process – “orakill sid thread”), you probably turn to:

alter system kill session 'sid, serial#, @inst_id' immediate;

(note (more...)

Configuring VNCR for Oracle RAC

By default on an Oracle RAC installation, the listeners are configured to allow any database to register with them.  There is no security out of the box to determine which databases may register.  While this makes it easy to create new databases without worrying about listener registration, this can cause potential problems in a real environment.

This can be dangerous working with RAC environments where the database registers with both a local and remote listener.  The (more...)

HAIP and Exadata

If you’ve run an exachk report, y0u may have seen the following message with regard to your databases:

Status Type Message Status On Details
FAIL Database Check Database parameter CLUSTER_INTERCONNECTS is NOT set to the recommended value db01:dbm011, db02:dbm012 View

This check is commonly seen when a database is created on Exadata without using the custom “Exadata” templates included with the database creation assistant.  These customized templates include a multitude of recommended parameter settings found in (more...)

Rolling Out-of-Place patching para Oracle Grid Infrastructure 12c y 11gR2: clonación en esteroides

Mi artículo más reciente para ToadWorld, dentro de una serie dedicada a aplicar patches con mínima suspensión del servicio. Ahora detallando cómo aplicar patches a Grid Infrastructure usando un Golden Image.

Convert 12cR1 non-RAC database to RAC database using rconfig

I have recently configured Active/Passive Failover cluster using Grid Infrastructure 12cR1 and wrote document on that subject. Now I plan to use this environment and convert "test12" database from Single-Instance to RAC database.

There are several ways to convert non-RAC database to RAC database:
- using Database Configuration Assistant (DBCA)
- Oracle Enterprise Manager
- rconfig command line utility
- manually

In this post I will describe how to perform conversion using rconfig utility.

Before (more...)

Database Shutdown With crsctl

I noticed something for the first time tonight when I was playing around in the Enkitec lab – something that I have been doing wrong for a while.  When working in the lab, I often rely on the crsctl command to shut down the entire cluster stack for me.  It’s really easy to use “crsctl stop cluster -all” followed by “dcli -l root -g ~/dbs_group /u01/app/ stop crs” to get everything down (more...)

12c Improvement in Database Service Management

Removing a service via srvctl has not historically resulted in the service being fully removed from the database and it would still be visible in DBA_SERVICES as show below in an database:

Create the service:

$ srvctl add service -d orcl -s demo -r "ORCL1,ORCL2"

Have (more...)

Oracle SOA Suite 11g tuning tips for Oracle RAC database 11.2

During my project work I had to tune the SOA dehydration store on more than one occasion. Through this posting I would like to share the tuning tips collected during these exercises. It is not a step-by-step guide, because with tuning there never is a 'one-size-fits-all' in my humble opinion, but I provide in general a guidance that you can use as a reference for your own situation. I will also refer to related Oracle (more...)

MGMTDB: Grid Infrastructure Management Repository

Original Post can be viewed at MGMTDB: Grid Infrastructure Management Repository

MGMTDB is new database instance which is used for storing Cluster Health Monitor (CHM) data. In 11g this was being stored in berkley database but starting Oracle database 12c it is configured as  Oracle Database Instance. In 11g, .bdb files (more...)

Openfiler on Virtualbox and 12c Oracle Flex ASM

Original Post can be viewed at Openfiler on Virtualbox and 12c Oracle Flex ASM

Last week Oracle released 12c database and Oracle blogosphere is bustling with lot of people posting details about new versions and setup. I too decided to take plunge and setup my own RAC cluster. I had (more...)

portmap: unrecognized service on RHEL6

Original Post can be viewed at portmap: unrecognized service on RHEL6

Quick note for people using NFS for shared storage on RAC database. Till RHEL5 we had to ensure nfs,nfslock and portmap service has to be running. These services are required otherwise you will get following errors while mounting database


Build an 11gR2 RAC cluster in VirtualBox in 1 Hour using OVM templates

[I originally posted this over at the Pythian blog. If you're not following it, you should! Way more content, by far smarter people than lil ol' me.]

After reviewing my blog post about running EBS OVM templates in VirtualBox, two of my teammates suggested that I work on something with potentially broader appeal. Their basic message was, "This is really cool for us EBS nerds, but what about the Core DBAs?"

So how does "11gR2 RAC in an hour" sound? :-) In this post, I'll demonstrate how to deploy the pre-built Oracle VM templates to create a two-node (more...)