TROUG Exadata SIG Meeting 2012

TROUG Özel İlgi Grubu (SIG) etkinliklerine hız kesmeden devam ediyor. Nisan ayında gerçekleşen "TROUG Exadata SIG Meeting 2012" de Türkiye'deki Exadata kullanıcıları bir araya geldi ve birbirinden faydalı sunumlar yapıldı. Etkinliğin sonunda ise "DWH Global Leaders" program yöneticisi Reiner Zimmermann'ın katıldığı bir sohbet toplantısı gerçekleştirildi. 

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Book Review: Oracle Database 11gR2 Performance Tuning Cookbook

I started reading this book last week, and I'm half way through right now. But i wanted to write this review because what i found in the book is fairly enough for this.
As the book's tittle expresses it involves examples, recipes, different test cases for almost all topics in the chapters. This is great, because just definitions and descriptions are not enough to fully understand the concept (especially) in a performance tuning book.
Book covers the most important performance tuning topics for an Oracle database. You'll find it useful even you're a developer or a dba. It describes the tuning methods with different aspects. Performance tuning is not like many other Oracle database topics becuse there is not a general "true" many times. A tuning method may halve the job duration in a database, where it may double the time for another database. This is the most important fact that you need to know when searching for tuning recommendations. The data type, database structure is very important in evaluating a tuning method. This book is explaining the tuning methods with almost every aspects. In which conditions we should use it or not and why. Here i want to share some highlighted parts of the topic "Index Clusters" which i think will help you see what i mean.

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My Presentation at OUG Ireland Conference 2012

I'll present at OUG Ireland Conference, Wednesday 21st March in Dublin. My presentation will be on Oracle Data Guard as in the Open World last year. I'm looking forward to present, listen to and meet with new people. There are a wide range of topics from Oracle professionals in the agenda. There will be 6 streams and 35 sessions in total. Well known Oracle ACEs/ACE Directors and Oracle employees will be on the stage. Some of the presentations are:

Roel Hartman, ACE Director - LOGICA - 5 Cool things you can do with HTML5
Mark Rittman, ACE Director - Rittman Mead - Inside Oracle Data Integrator 11g
Simon Haslam, ACE Director - Veriton Limited - WebLogic for DBAs
Frits Hoogland, ACE Director - VX Company - About multiblock reads
Lonneke Dikmans, ACE Director - Vennster - How do we integrate our packaged app?
Grant Ronald, ACE - Oracle - What is The Future of Forms?
Marcin Przepiorowski, ACE - Amazon - Performance troubleshooting using Active Session History
David Hall, ACE - Peak Indicators Ltd - OBIEE in Education in Action
Brendan Tierney, ACE - Dublin Institute of Technology ; Co-Presenter Antony Heljula – Peak Indicators Ltd - Getting Started with Oracle Data Miner

Event page is here and the full agenda is here.

Automatic Block Media Recovery on Maximum Performance Mode

Automatic Block Media Recovery is a cool 11gR2 feature. If the database on which a corruption occurs is associated with a real-time query physical standby database, then the database automatically attempts to perform block media recovery. The primary database searches for good copies of blocks on the standby database and, if found, repairs the blocks with no impact to the query that encountered the corrupt block. Only if the database is unable to repair the corruption is the Oracle physical block corruption message (ORA-1578) displayed.

Oracle Database High Availability Overview11g Release 2 (11.2) guide explains the requirements of this feature as below:

Automatic block repair requires the use of the Oracle Active Data Guard option so that you can open a physical standby database for read-write I/O. Also, note that this feature requires that Oracle Data Guard is running in maximum availability mode and has the LOG_ARCHIVE_DEST_n initialization parameter set to the SYNC redo transport mode

But, in a case we experienced in my company last week, we saw in the primary database alert.log, that the database tried to use ABMR in a Maximum Performance Data Guard configuration. Here is the log:

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A Grid Infrastructure Installation Adventure

I was very used to create ASM instance manually before 11gR2. With 11gR2 we must to install Grid Infrastructure even on sigle instance databases if we’re going to use ASM. In my last installation i had strange errors that i’ll share below. First error was complaining about the password and the log file is:

INFO: Executing ASMCA

INFO: Command /u01/app/oracle/product/11.2.0/grid/bin/asmca -silent -oui_internal -configureASM -diskString '/dev/ORACLE/ASMDISKS/*' -diskGroupName DATA -diskList /dev/ORACLE/ASMDISKS/hostx_asm0,/dev/ORACLE/ASMDISKS/hostx_asm1 -redundancy EXTERNAL

INFO: ... GenericInternalPlugIn.handleProcess() entered.

INFO: ... GenericInternalPlugIn: getting configAssistantParmas.

INFO: ... GenericInternalPlugIn: checking secretArguments.

INFO: ... GenericInternalPlugIn: starting read loop.

INFO: Read: SYS_PASSWORD_PROMPT

INFO: Processing: SYS_PASSWORD_PROMPT for argument tag -sysAsmPassword

INFO: Read: ASMSNMP_PASSWORD_PROMPT

INFO: Processing: ASMSNMP_PASSWORD_PROMPT for argument tag -asmMonitorPassword

INFO: End of argument passing to stdin

INFO: Read:

INFO: Read: Configuring ASM failed with the following message:

INFO: Read: Adding Monitor user failed. The following error occured:

INFO: Read: ORA-00922: missing or invalid option

INFO: Read:

INFO: Read:

INFO: Completed Plugin named: Automatic Storage Management Configuration Assistant

INFO: Automatic Storage Management Configuration Assistant failed.

INFO: Automatic Storage Management Configuration Assistant failed.

INFO: ConfigClient.executeToolsInAggregate action performed

INFO: Exiting ConfigClient.executeToolsInAggregate method                                          INFO: Calling event ConfigToolsExecuted

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[INS-20802] Oracle Net Configuration Assistant failed

I had the following error on 11gR2 Grid Infrastructure installation:

[INS-20802] Oracle Net Configuration Assistant failed. 

The plug-in failed in its perform method

tail -50 /u01/app/oraInventory/logs/installActions2012-01-06_09-45-58AM.log

INFO: Oracle Net Listener Startup:

INFO: The information provided for this listener is currently in use by other software on this computer.

INFO:     Listener start failed.

INFO: Check the trace file for details: /u01/app/oracle/cfgtoollogs/netca/trace_Ora11g_gridinfrahome1-1201069AM5717.log

INFO: Oracle Net Services configuration failed.  The exit code is 1

WARNING:

 Log file indicates that it’s not possible to start listener, because “The information provided for this listener is currently in use by other software on this computer.” Not very helpful, so i checked the trace file.

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Book Review: Oracle WebCenter 11g PS3 Administration Cookbook

I knew a little about Webcenter and Packt's Oracle Webcenter 11g book was very helpful for me to learn about the new version and developing the administration skills. Yannick Ongena did a greate job on this book with a uniqe style of teaching. In this book topics are covered with 4 dimensions.
"Getting ready"
"How to do it..."
"How it works..."
and  "There's more..."



With this way of teaching, the prerequests for testing the case are defined, the way to implement the topic on WebCenter is defined, "what is happening behind the scenes" is explained and the details of the issue are told. I think this is a great way of explaning a test case.

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Book Review: Oracle Enterprise Manager Grid Control 11gR1: Business Service Management

Here is another greate book i read and recommend, published by Packt and written by  Ashwin Kumar Karkala and Govinda Raj Sambamurthy. This is about Oracle Enterprise Grid Control. Book is named with "Business Service Management" to impress the capabilities of Grid Control. Grid Control is not just for your Database Monitoring needs, but also for a complete service management which includes servers, applications, clusters also building and monitoring business services. This book is very well detailed to understand how big are the boundaries of Grid Control in monitoring the IT infrastructure.


Book starts with defining Business Service Management, how to manage the complexities of today's data centers and also touch upon Information Technology Infrastructure Library (ITIL) guidelines. Then continues with modelling groups and systems. OEM Grid Control offers capabilities to model IT infrastructure as systems, groups, and redundancy groups. Book covers all the three areas. Then modeling services like generic service target, web application target, forms application, and so on is discussed. A detailed topic of "Service Modeling Using Synthetic Transactions", dives deeper into the area of active monitoring using beacons and service tests. Book continues with "Modeling Service Metrics", "Service-Level Management", "Modeling Composite Business Services" and "Real-Time Business Service Monitoring". At the end you'll find a chapter which provides some of the best practices and recommendations around Business Service Management with OEM Grid Control. This chapters includes very valuable real world scenarios which add this book a great worth. 


I strongly advise this book for current users of Enterprise Manager Grid Control to dive deep into details and take advantage of Grid Control in the widest sense. Also potential users of Grid Control will find very valuable information about the capabilities of this software.


You can find information and buy this book here: http://link.packtpub.com/GZNpvq. 


Thanks to Ashwin Kumar Karkala and Govinda Raj Sambamurthy for the nights and weekends they spend for this book :)

RMAN Channels, Parallelism, Multisection Backups & Multiplexing

I wanted to summirize some complicated RMAN concepts, using the "11gR2 Backup and Recovery User's Guide" definitions.

Channel & Parallelism

The number of channels available for use with a device when you run a command determines whether RMAN reads from or write to this device in parallel while performing the command. When the work is done in parallel, the backup of the files is done by more than one channel. Each channel may back up more than one file, but unless a multisection backup is performed, no file is backed up by more than one channel.

The number of channels available for a device type when you run a command determines whether RMAN reads or writes in parallel. As a rule, the number of channels used in executing a command should match the number of devices accessed. Thus, for tape backups, allocate one channel for each tape drive. For disk backups, allocate one channel for each physical disk, unless you can optimize the backup for your disk subsystem architecture with multiple channels. Failing to allocate the right number of channels adversely affects RMAN performance during I/O operations.

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My OOW 2011 Presentation

I submitted for Open World 2011 with a presentation titled "Effectively using Oracle Data Guard for multiple purposes". After the voting phase, Oracle reviewed and accepted my session. Here are some details of my presentation. Hope to see you there.

Type:                               Conference
Presenter:                         Emre Baransel
Primary Track Database:   High Availability
Optional Track:                 Performance and Scalability
Session Category:             Best Practices
Attendee Role:                  Database Administrator and Architect

Abstract:
Turkcell, the leader GSM operator of Turkey, has a large disaster recovery environment which includes 30 standby databases with different versions & characteristics, on various storage options and operating systems. In this session, hear the Turkcell scenario of using standby databases as a source for datawarehouse extraction and test purposes, in the meantime keeping the primary aim of disaster recovery. Learn the challenges arising from database version deficiencies, RTO&RPO objectives, performance needs and solutions for these problems. 11g features such as Active Data Guard, snapshot standby, RMAN integration, compression of redo traffic, lost-write detection, heterogeneous configuration will also be touched on.