ORA-17612: Failed to discover Oracle Disk Manager Library, return value 2

DBA’s you must have come across below error post cloning a RAC database to single instance node

RAC database shared server storage must have been managed by third party cluster vendor tools like VERITAS or so

Refer below steps to resolve it 


ORA-17612: Failed to discover Oracle Disk Manager Library, return value 2


Improving FTS oracle

This blog is written after resolving sev1 performance issue post DB migration to new setup

Issue: Sql Full table Scan (FTS) Slowness due to change in execution plan post db migration

Recently we have migrated 11gr2 Single Node prod. DB (ASM/AIX) to 11gr2 RAC 2 node (Linux) using Data Pump, since then started facing the below issue

ORA-01157 ORA-01110 ORA-27037 ASM file Addition Issues

This blog is intended to make DBA’s aware of what havoc it will create if we misplace a command of datafile addition in ASM disk group especially in RAC.

Last night I missed the ‘+’ sign of DG01 while adding a tempfile in new prod RAC DB resulted in below error & file creation in default local/non-shared location of $ORACLE_HOME/dbs
Which is not readable by other instance, being a temp file it had less impact on DB but such incident can happen while adding data DB files which will lead to db outage

My Mistake: 

I missed ‘+’ sign of DG01

SQL>alter tablespace TEMP add tempfile 'DG01' size 20G;

Impact: Any Running session using this file will receive & log error in alert log
SQL> select * from dba_temp_free_space;
ORA-01157: cannot identify/lock data file 1010 - see DBWR trace file
ORA-01110: data file 1010: '/u01/app/ora11g/product/11.2.0/db_1/dbs/DG01'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory

What is Oracle Database ?

An Oracle Database is a Relational Database management System used to store & retrieve the related information.

An Oracle Database server/instance consists of shared memory structure, background processes & storage which handles the functional requirement to manage concurrent & shared data access by users.

Oracle Database product has evolve though its 8i, 9i, 10g & 11g version

Oracle database server is a part of multitier architecture includes Client Machine/Webserver, Middleware Application & Database Server.

Error connecting ASM ORA-15055: unable to connect to ASM instance Fatal NI connect error 12547 ORA-12547: TNS:lost contact

This Blog is intended to resolve below errors observed in DB alert log file due connectivity issue between DB Instance & ASM disk/Instance


Fatal NI connect error 12547, connecting to:
TNS-12547: TNS:lost contact
    ns secondary err code: 12560
    nt main err code: 517

Cross OS Platform Oracle DB Migration Using RMAN


Document highlights cross OS platform migration of Oracle 10g database from HP UX to Sun using RMAN convert method.  

Oracle Doc. For Reference:
Cross-Platform Migration on Destination Host Using RMAN Convert Database [ID 414878.1]

Activity Index:

On Source:

           1. Verify invalid objects on source, invalid indexes, db component status
           2. Re-open DB in read only mode
           3. Verify external references & transportable compatibility w.r.t target platform
           4. Generate transport & convert script, parameter file using RMAN
           5. Shut down database,copy datafiles & transport/convert script/pfile to Target

On Target:

 6. Prepare pfile & create controlfile 
 7. Perform RMAN convert on SYSTEM/UNDO datafiles using convert script generated on source
 8. Re-create Control file with converted datafiles
 9. Execute transport script for migration 
10. Rename datafiles,create spfile 
11. Verify invalid objects, invalid indexes, db component status

Activity Steps:

ORA-00600 ORA-01114 ORA-27063 WARNING: failed to write mirror WARNING: IO Failed

Post related to below ORA- errors

ORA-00600: internal error code, arguments: [17183], [0x11041A2C8], [], [], [], [], [], []
ORA-01114: IO error writing block to file  (block # )
ORA-27063: number of bytes read/written is incorrect
WARNING: failed to write mirror side 0 of virtual extent  of file in group
WARNING: IO Failed.  au: diskname:


ORA-00600: internal error code, arguments: [17183], [0x11041A2C8], [], [], [], [], [], []
ORA-01114: IO error writing block to file  (block # )
ORA-01114: IO error writing block to file 201 (block # 647794)
ORA-27063: number of bytes read/written is incorrect

Oracle 10g Standard Edition Installation & Features


Document highlights oracle standard edition installation steps, database hardening as per SOX compliances and issues faced during a project setup along with best practices

Table of Content(TOC):

1.     Platform OS/DB Version  

2.     How to download oracle software
3.     Difference between Enterprise & Standard Edition

4.     Server Pre-requisites
5.     Software & database Installation

6.     Issues faced
7.     Practices

Disabling Oracle Performance Pack

Method 1:  Revoking Management Pack Access through OEM
Home Page>setup>Management Pack Access <Remove Access> <Apply>

Method 2:
ΓΌ  Step 1

Oracle Performance Tuning I

Oracle Performance Tuning : Tuning Pack 

Oracle has introduced Performance tuning & Diagnostic Pack (10g onwards), let me brief you about Tuning Pack first

Oracle Tuning Pack :

The Oracle Tuning Pack provides database administrators with expert performance management for the Oracle environment, including SQL tuning and storage optimizations. The Oracle Diagnostic Pack is a prerequisite product to the Oracle Tuning Pack. Therefore, to use the Tuning Pack, you must also have a Diagnostic Pack. The Tuning Pack includes the following features:

1.SQL Access Advisor :

ORA-00600 , PLS-707, ORA-06553, ORA-06544

ORA-06553 unsupported construct or internal error 

Follow Below for errors observed in Oracle 8i,9i DB's due to unsupported pl/sql tool version