Review: Oracle RAC Performance Tuning

Some time ago, I received a free review copy of Brian Peasland‘s recent book, Oracle RAC Performance Tuning.

First, a note on my RAC background: I spent 7 years on Oracle’s RAC Support team. When customers had an intractable RAC performance issue, I was on the other end of the “HELP!” line until it was resolved.

I made Brian’s acquaintance through the MOS RAC Support forum, where Brian stood out as a frequent (more...)

racattack, meet ansible-oracle!

A while back I was approached by Jeremy Schneider, who is one of the original contributors to the racattack project and he wanted to know if I was interested in integrating ansible-oracle with the RAC Attack automation project, and of course I was! The idea was to provide a completely hands off installation of an […]

Creating a RAC Flex Cluster using ansible-oracle

As of version 1.3 it is possible to create a RAC Flex Cluster using ansible-oracle. From a ansible-oracle configuration perspective there is not a huge difference from a normal ‘standard’ cluster, basically a few new parameters. There are other differences though, specifically in how you have to run the playbook and deal with the inventory configuration. In […]

ansible-oracle, the RAC edition

First off, I’ll be setting up page, where I intend to have a complete list of parameters used in all roles and a description of what they actually do. Up until now I’ve kept it in a file in the github repo, but I think it will be easier to maintain this way. The page is […]

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.





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 11.2.0.3 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

(more...)

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...)

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, b.name,
a.value, d.used_urec, d.used_ublk
FROM gv$sesstat a, v$statname  (more...)

On demand AWR Report Generator, for Many Node Cluster

update ( 10/10/2012 ): I have changed the script to make work better with hourly requests at it was causing issues. Thanks to Dominic Brooks for the trick
update ( 11/10/2012 ): Added ADDM and Global report generation

Since I got turbo boost (over 1000 hits a day-wooow) from Tanel Poder the Great, better I write something to deserve the fame. This one is a real quick one which made my life easier.

On my second week at current company, I had to cover Exadata for 2 weeks which were completely nightmare due to some problems. I had to (more...)

Oracle Database Appliance (ODA) Installation / Configuration

Earlier Oracle announced the Oracle Database Appliance which is a really cool RAC-in-a-box. And here at Enkitec office we are very lucky to get our hands dirty and play with this new beast ;) On the photo below you will see the Oracle Database Appliance.

Andy Colvin has some detailed reviews about the Oracle Database Appliance.. check out these links if you want to see the internals of the machine
http://blog.oracle-ninja.com/2011/09/inside-the-oracle-database-appliance-part-1/
http://blog.oracle-ninja.com/2011/09/oracle-announces-oracle-database-appliance/

But this post will walk you through the installation and configuration of the Oracle Database Appliance.. well all I can say.. at the end of (more...)

How to list files on a directory from Oracle Database.

Couple of days ago I had an interesting request, “How can I see the contents of nfs_dir”?

The problem:

We were using DBFS to store our exports. This was the perfect solution as the business could “see” the files on the destination folder, but it did not meet our requirements performance wise on our Exadata.

We have decided to mount NFS and performance did improve, but we had a different problem. NFS is mounted on the database server and business do not have access for security reasons and segregation of duties.

Since then, the export jobs run, but business could (more...)

ORA-16072: a minimum of one standby database destination is required

This is a quick post regarding the error on the subject. This is the second time it happens to me, so I thought I will write a bit about it.

The problem:

I am refreshing one of my UAT environments (happens to be a Full Rack Exadata) using Oracle RMAN duplicate command. Then the following happens (on both occasions).

1.- Duplicate command fails (lack of space for restoring archivelogs, or any other error). This is can be fixed quite easy.

2.- following error while trying to open the database after restore and recover has finished:

SQL> alter database  (more...)

Oracle: Rename single/RAC Database

Method 1: Recreate control file with the new DB name, the old tried and tested method.
Method 2: Use new utility called NID
Steps to rename Databases using the new NID utility:
1.) Stop database

[oracle@testing1]~% srvctl status database -d test
Instance test1 is running on node testing1
Instance test2 is running on node testing2

srvctl stop database -d test


2.) startup mount the database:

[oracle@testing1]~% sqlplus / as sysdba

SQL*Plus: Release 11. (more...)

Check status voting disk.

This is a quick blog as to how to check the status of Voting Disks.

The problem:

You receive a call/email from you 1st line support with something similar to:

----
[cssd(9956)]CRS-1604:CSSD voting file is offline: o/xxx.xxx.xx.xx/SYSTEMDG_CD_05_SSSSSin; details at (:CSSNM00058:) in /apps/oracle/grid_11.2/log/sssss/cssd/ocssd.log.
----

The solution:

Easy to check using crsctl:

oracle$ crsctl query css votedisk

## STATE File Universal Id File Name Disk group
-- ----- ----------------- --------- ---------
1. ONLINE a0a559213xxxxxxffa67c2df0fdc12 (o/xxx.xxx.xx.xx/SYSTEMDG_CD_05_SSSSSin) [SYSTEMDG]
2. ONLINE 121231203xxxxxxfc4523c5c34d900 (o/xxx.xxx.xx.xx/SYSTEMDG_CD_05_SSSSSin) [SYSTEMDG]
3. ONLINE a6b3c0281xxxxxxf3f6f9f1fd230ea (o/xxx.xxx.xx.xx/SYSTEMDG_CD_05_SSSSSin) [SYSTEMDG]

Located 3 voting disk(s).

As always, comments are welcome.


Creating listeners on the private network interfaces of RAC nodes or use that Exadata Infiniband network

In general usage, everyone configures tns listeners on the public interfaces of RAC nodes so that clients can connect through the public network. Conventionally the private network interfaces are used for the interconnect traffic so most people do not open them to the application because the application traffic may interfere with the interconnect messaging.

But what if we have a high-speed and high-bandwidth interconnect network that some applications can also use for fast communication to the nodes? Can we create tns listeners on the private interfaces, if we can how? This high-speed interconnect network is especially true for Exadata where (more...)