Oracle 12c RAC on Oracle Linux 6 and 7 using NFS

linux-tuxFollowing on from the last post, I’ve brought my NFS RAC stuff up to date also.

I noticed I had not done a RAC install using NFS on Oracle Linux 6, so I threw that in for good measure too. :)

Just as a little (more...)

Issue with Perl in $ORACLE_HOME during installs

I’ve been doing some Enterprise Manager installs a bit more lately. At the same time, I’ve been working on Data Integration items such as GoldenGate and ODI.  What these products have in common are that they require an Oracle Database for a repository.  Needless to say I’ve been installing a lot of databases in test and production environments.  The one thing that has been consistent is the issue I keep seeing (more...)

Fixing a problem with the ASM spfile preventing RAC 12c from starting

This is a little note to myself on how to fix a corrupt spfile in clustered ASM. I hope you find it useful, too.

Let’s assume you made a change to the ASM (server) parameter file that causes an issue. You are most likely to notice this once CRS is restarted but parts of the stack fail to come up. If “crsctl check crs” mentions any component not started you can try to find out (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...)

The Importance of the In-Memory DUPLICATE Clause for a RAC System

With the INMEMORY clause you can specify 4 sub-clauses:

  • The MEMCOMPRESS clause specifies whether and how compression is used
  • The PRIORITY clause specifies the priority (“order”) in which the segments are loaded when the IMCS is populated
  • The DISTRIBUTE clause specifies how data is distributed across RAC instances
  • The DUPLICATE clause specifies whether and how data is duplicated across RAC instances

The aim of this post is not to describe these attribues in detail. Instead, (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...)

Clusterware 12c and Restricted Service Registration for RAC

Topic: This post is about exploring the mechanisms used by Oracle Clusterware to restrict remote service registration, i.e. the 12c new feature "Restricting Service Registration for Oracle RAC Deployments"

Why is this useful? This improvement of 12c clusterware and listeners over the 11.2 version is useful mainly for security purposes, for example as a measure against TNS poisoning attacks (see also CVE-2012-1675), and it is particularly relevant for (more...)

Oracle GI 12.1 error when using NFS

I had quite an interesting case recently where I had to build stretch cluster for a customer using Oracle GI 12.1 and placing quorum voting disk on NFS. There is a document at OTN regarding the stretch clusters and using NFS as a third location for voting disk but it has information for 11.2 only as of the moment. Assuming there is no difference in the NFS parameters I used the Linux parameters (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...)

Oracle Database Appliance (ODA) Patch 2.4 is out

This is just a post ot point out that ODA Patch 2.4 is out. ODA Patch 2.4 requires 2.2 or above to install.
A couple of Highlights of this release seem to be
  1. Enhanced odachk 2.16
  2. A trace file analyzer 
  3. The ability to now use normal (more...)

Scipt to automatically move RAC 11gR2 services back to preferred instances

When instance fails in Oracle RAC, the services that were using this instance as a preferred instance are automatically relocated to instances marked as available for this service. But after the failed instance recovers and starts up again, the relocated services are not moved back and need manual srvctl relocate service command from administrator to move them back.

Here is a little Bash script to automate this process. Oracle Clusterware (Grid Infrastructure) can execute user callout scripts on FAN events, like INSTANCE up/down. Place this script under $GRID_HOME/racg/usrco/ and set the execute bits on the file. Then clusterware will execute (more...)

SQL Monitor details for later tuning.

Tuning has always being good fun and something like a challenge for me.

From time to time we are being asked to find out why something did run slow while you are sleeping; answering this question is, in most cases, a challenge.

The problem:

My batch did run slow last night, can you let us know why? Or why did this query run slow? Are questions we, as DBAs, have to answer from time to (more...)

Who is using your Undo space? – Improved Script

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Hi folks!
I have extended the Undo usage scripts to include two additional indicators:
1) undo change vector size statistics
2) Used undo records/blocks

and support for RAC infrastructure, so you can spot the hungriest UNDO eaters for any given instance.

Then the script for Oracle 11g is as follows:
set pagesize 400
set linesize 140
col name for a25
col program for a50
col username for a12
col osuser for a12
SELECT a.inst_id, a.sid, c.username, c.osuser, c.program,,
a.value, d.used_urec, d.used_ublk
FROM gv$sesstat a, v$statname  (more...)