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Archive for October, 2012

Oracle Secure Backup: Configuration

Posted by FatDBA on October 31, 2012

  • Steps to Configure Oracle Secure Backup (OSB):

Step 1. As the root user, check if the uncompress utility is installed on the system. If it is not,
create a symbolic link pointing to the gunzip utility:

(This is an important per-requisite and this is needed by the installed to uncompress files to installation directory and Mostly this does not comes pre-installed with Linux OS, create symbolic link with the Gunzip utility or install an RPM for this)
[root@lin32 ~]# uncompress
-bash: uncompress: command not found
[root@lin32 ~]# ln -s /bin/gunzip /bin/uncompress
Step 2. Create a directory for the download, and then issue the change directory command to
that directory:
[root@lin32 ~]# mkdir download
[root@lin32 ~]# cd download/
Step 3. Download OSB into the download directory and then unzip the product:
[root@lin32 download]# ls –l
total 43864
-rw-r–r– 1 root root 44866571 Jan 19 20:31 osb-10.3.0.1.0_linux32_release.zip
[root@lin32 download]# unzip osb-10.3.0.1.0_linux32_release.zip
Archive: osb-10.3.0.1.0_linux32_release.zip
creating: osb-10.3.0.1.0_linux32_cdrom090504/
extracting: osb-10.3.0.1.0_linux32_cdrom090504/OSB.10.3.0.1.0_LINUX32.rel
creating: osb-10.3.0.1.0_linux32_cdrom090504/doc/
creating: osb-10.3.0.1.0_linux32_cdrom090504/doc/dcommon/
creating: osb-10.3.0.1.0_linux32_cdrom090504/doc/dcommon/css/
inflating: osb-10.3.0.1.0_linux32_cdrom090504/doc/dcommon/css/blafdoc.css
inflating: osb-10.3.0.1.0_linux32_cdrom090504/doc/dcommon/css/bp_layout.css

inflating: osb-10.3.0.1.0_linux32_cdrom090504/welcome.html
inflating: osb-10.3.0.1.0_linux32_cdrom090504/doc.tar
Step 4. Create the directory where the install will place OSB files:
[root@lin32 download]# mkdir -p /usr/local/oracle/backup

Step 5. Issue the change directory command to the OSB destination and run setup:
[root@lin32 download]# cd /usr/local/oracle/backup/
[root@lin32 backup]# /root/download/osb-10.3.0.1.0_linux32_cdrom090504/setup
The following output is returned:
Welcome to Oracle’s setup program for Oracle Secure Backup. This program loads
Oracle Secure Backup software from the CD-ROM to a filesystem directory of your
choosing.
This CD-ROM contains Oracle Secure Backup version 10.3.0.1.0_LINUX32.
Please wait a moment while I learn about this host… done.
– – – – – – – – – – – – – – – – – – – – – – – – – – –
1. linux32
administrative server, media server, client
– – – – – – – – – – – – – – – – – – – – – – – – – – –
Loading Oracle Secure Backup installation tools… done.
Loading linux32 administrative server, media server, client… done.
– – – – – – – – – – – – – – – – – – – – – – – – – – –
Oracle Secure Backup has installed a new obparameters file.
Your previous version has been saved as install/obparameters.savedbysetup.
Any changes you have made to the previous version must be made to the new obparameters file.
Would you like the opportunity to edit the obparameters file
Please answer ‘yes’ or ‘no’ [no]:
Step 6. Leaving the default parameters for now, press ENTER to choose the default answer. The
following output is returned:
– – – – – – – – – – – – – – – – – – – – – – – – – – –
Loading of Oracle Secure Backup software from CD-ROM is complete.
You may unmount and remove the CD-ROM.
Would you like to continue Oracle Secure Backup installation with ‘installob’ now?
(The Oracle Secure Backup Installation Guide contains complete information about
installob.)
Please answer ‘yes’ or ‘no’ [yes]:
Step 7. Again, press ENTER to choose the default answer. The following output is returned:
– – – – – – – – – – – – – – – – – – – – – – – – – – –
Welcome to installob, Oracle Secure Backup’s installation program.
For most questions, a default answer appears enclosed in square brackets.
Press Enter to select this answer.
Please wait a few seconds while I learn about this machine… done.
Have you already reviewed and customized install/obparameters for your Oracle
Secure Backup installation [yes]?
Step 8. Again, press ENTER to choose the default answer and to leave the default parameters. The
following output is returned:
– – – – – – – – – – – – – – – – – – – – – – – – – – –
Oracle Secure Backup is not yet installed on this machine.
Oracle Secure Backup’s Web server has been loaded, but is not yet configured.
Choose from one of the following options. The option you choose defines the
software components to be installed.

Configuration of this host is required after installation completes.
You can install the software on this host in one of the following ways:
(a) administrative server, media server and client
(b) media server and client
(c) client
If you are not sure which option to choose, please refer to the Oracle Secure
Backup Installation Guide. (a,b or c) [a]?
Step 9. You are going to install all three components of OSB on the same server, so again press
ENTER to choose the default answer. The following output is returned:
Beginning the installation. This will take just a minute and will produce
several lines of informational output.
Installing Oracle Secure Backup on lin32 (Linux version 2.6.18-53.el5)
You must now enter a password for the Oracle Secure Backup encryption key store.
Oracle suggests you choose a password of at least 8 characters in length,
containing a mixture of alphabetic and numeric characters.
Please enter the key store password:
Re-type password for verification:
Step 10. Enter the OSB encryption key twice. The key is not displayed. You will see the
following output:
You must now enter a password for the Oracle Secure Backup ‘admin’ user. Oracle
suggests you choose a password of at least 8 characters in length, containing a
mixture of alphabetic and numeric characters.
Please enter the admin password:
Re-type password for verification:
Step 11. Enter the admin password twice. The password is not displayed. You will see the
following output:
You should now enter an email address for the Oracle Secure Backup ‘admin’ user.
Oracle Secure Backup uses this email address to send job summary reports and to
notify the user when a job requires input. If you leave this blank, you can set it
later using the obtool’s ‘chuser’ command.
Please enter the admin email address:
Step 12. Leave the e-mail address blank for now. The following output is returned:
generating links for admin installation with Web server
updating /etc/ld.so.conf
checking Oracle Secure Backup’s configuration file (/etc/obconfig)
setting Oracle Secure Backup directory to /usr/local/oracle/backup in /etc/obconfig
setting local database directory to /usr/etc/ob in /etc/obconfig
setting temp directory to /usr/tmp in /etc/obconfig
setting administrative directory to /usr/local/oracle/backup/admin in /etc/obconfig
protecting the Oracle Secure Backup directory
creating /etc/rc.d/init.d/observiced
activating observiced via chkconfig
initializing the administrative domain
****************************** N O T E ******************************
On Linux systems Oracle recommends that you answer no to the next two questions.
The preferred mode of operation on Linux systems is to use the /dev/sg devices for

attach points as described in the ‘ReadMe’ and in the ‘Installation and
Configuration Guide’.
Is lin32 connected to any tape libraries that you’d like to use with Oracle Secure Backup [no]?
Is lin32 connected to any tape drives that you’d like to use with Oracle Secure
Backup [no]?
Step 13. Since, in this example, you use a Linux system, answer “no,” as recommended by
Oracle, and configure the media server later. The following summary is returned:
Installation summary:
Installation Host OS Driver OS Move Reboot
Mode Name Name Installed? Required? Required?
admin lin32 Linux no no no
Oracle Secure Backup is now ready for your use.
The OSB administrative server, media server, and client are now installed. The OSB Web tool
is used to configure the tape library and tape drives.

Once configured launch your Web browser and supply the URL of the host running Oracle Secure Backup. Use the following syntax, where hostname can be a fully qualified domain name:

https://hostname
https://localhost.localdomain

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Oracle Secure Backup ?

Posted by FatDBA on October 31, 2012

What is Oracle Secure backup ?
Oracle Secure Backup is centralized tape backup management software providing secure data protection for heterogeneous file systems and the Oracle Database. Oracle has its own media management software solution, Oracle Secure Backup (OSB). OSB is a fully integrated, RMAN-to-tape solution that does not require any third-party vendor software plug-in, and OSB has come a long way since its introduction in 10gR2.

In Oracle 10gR2 and Oracle 11g, you can utilize OSB to provide free backup to tape functionality, provided that you have a single tape head and it is attached directly to the server that contains the Oracle database that you want to back up. In addition to tape backup, OSB delivers an integrated Oracle database backup to third-party cloud (Internet) storage, through the Oracle Secure Backup Cloud Module. Oracle Secure Backup offers two tape management editions: OSB and OSB Express.

Oracle Secure Backup Interfaces:
You can interact with Oracle Secure Backup by means of the following tools:
– Oracle Secure Backup Web tool
– Oracle Secure Backup command-line interface
– Oracle Enterprise Manager

OSB Roles and Admin Domains:
Administrative server:
Each administrative domain must have exactly one administrative server. This server stores data pertinent to the operation of the administrative domain in a set of configuration files. Metadata relating to backup and restore operations is also stored on the administrative server in a backup catalog.
The administrative server runs the scheduler, which starts and monitors jobs within the administrative domain.

Media Server
A media server has one or more secondary storage devices, such as a library and tape drives, connected to it. At a minimum, a media server must have one standalone tape drive. Many media servers utilize robotic tape libraries.

Client
A client host is a host that has locally-accessed data that is backed up or restored by Oracle Secure Backup. Any host where Oracle Secure Backup is installed, or that contains data that Oracle Secure Backup accesses through Network Data Management Protocol (NDMP), can act as a client. Each client host is associated with one administrative server.

 

 

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Standby: Protection Modes.

Posted by FatDBA on October 30, 2012

The protection modes run in the order from highest (most data protection) to the lowest (least data protection):

Minimum Requirements for Data Protection Modes
Maximum Protection Maximum Availability Maximum Performance
Redo Archival Process LGWR LGWR LGWR or ARCH
Network Transmission Mode SYNC SYNC ASYNC when using LGWR process. Not applicable when using ARCH process.
Disk Write Option AFFIRM AFFIRM NOAFFIRM
Standby Redo Logs Required? Yes Required for physical standby databases only. Standby redo logs are not supported for logical standby databases. Required for physical standby databases using the LGWR process.
Database Type Physical only Physical and Logical Physical and Logical

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Re-Creating the Control File: RMAN Effects during the activity.

Posted by FatDBA on October 29, 2012

It used to be that certain conditions required the occasional rebuild of the database control
file. If you use RMAN and you do not use a recovery catalog, be very careful of the control file
rebuild. When you issue the command

alter database backup control file to trace;

the script that is generated does not include the information in the control file that identifies
your backups. Without these backup records, you cannot access the backups when they are
needed for recovery. All RMAN information is lost, and you cannot get it back. The only
RMAN information that gets rebuilt when you rebuild the control file is any permanent
configuration parameters you have set with RMAN.
If you back up the control file to a binary file, instead of to trace, then all backup
information is preserved. This command looks like the following:

alter database backup controlfile to ‘/u01/backup/bkup_cfile.ctl’;

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Cumulative vs Differential vs Full Backups

Posted by FatDBA on October 27, 2012

Types of backups:

1. Full Backup or zero level backup.

2. Incremental Backup’s: Changed noted by the backup after a full backup. Broadly divided into two types

– Differential Incremental Backup (Figure a)

– Cumulative Incremental Backup (Figure b)

Level 0 and Level 1 Incremental Backups

Incremental backups can be either level 0 or level 1. A level 0 incremental backup, which is the base for subsequent incremental backups, copies all blocks containing data, backing the datafile up into a backup set just as a full backup would. The only difference between a level 0 incremental backup and a full backup is that a full backup is never included in an incremental strategy.

A level 1 incremental backup can be either of the following types:

  • A differential backup, which backs up all blocks changed after the most recent incremental backup at level 1 or 0
  • A cumulative backup, which backs up all blocks changed after the most recent incremental backup at level 0

Incremental backups are differential by default.

Differential Incremental Backups

In a differential level 1 backup, RMAN backs up all blocks that have changed since the most recent cumulative or differental incremental backup, whether at level 1 or level 0. RMAN determines which level 1 backup occurred most recently and backs up all blocks modified after that backup. If no level 1 is available, RMAN copies all blocks changed since the level 0 backup.

The following command performs a level 1 differential incremental backup of the database:

RMAN> BACKUP INCREMENTAL LEVEL 1 DATABASE;

If no level 0 backup is available, then the behavior depends upon the compatibility mode setting. If compatibility is >=10.0.0, RMAN copies all blocks changed since the file was created, and stores the results as a level 1 backup. In other words, the SCN at the time the incremental backup is taken is the file creation SCN. If compatibility <10.0.0, RMAN generates a level 0 backup of the file contents at the time of the backup, to be consistent with the behavior in previous releases.

Figure  Differential Incremental Backups (Default)

Description of Figure 4-1 follows

Cumulative Incremental Backups

In a cumulative level 1 backup, RMAN backs up all the blocks used since the most recent level 0 incremental backup. Cumulative incremental backups reduce the work needed for a restore by ensuring that you only need one incremental backup from any particular level. Cumulative backups require more space and time than differential backups, however, because they duplicate the work done by previous backups at the same level.

The following command performs a cumulative level 1 incremental backup of the database:

BACKUP INCREMENTAL LEVEL 1 CUMULATIVE DATABASE; # blocks changed since level 0

Figure Cumulative Incremental Backups

Description of Figure 4-2 follows

Posted in Uncategorized | Tagged: | 1 Comment »

News: ASMlib will not be certified or supported on Red Hat Enterprise Linux 6.

Posted by FatDBA on October 25, 2012

For More Click or go to News section of the Blog:

https://oracleant.wordpress.com/news/

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Real-Time Apply Error: ORA-38500: ‘USING CURRENT LOGFILE option not available without stand’

Posted by FatDBA on October 25, 2012

Hi Folks,

Going to discuss about one of the most recent problem that i faced while configuring/activating the Real-Time Apply service on one of the standby database.

(Using Oracle 10g r2)
Prior Status:
SQL> SELECT RECOVERY_MODE FROM V$ARCHIVE_DEST_STATUS WHERE DEST_ID=2 ;

RECOVERY_MODE
———————–
MANAGED

To start real-time apply i used CURRENT LOGFILE clause but received below provided error message:

SQL> alter database recover managed standby database disconnect using current logfile;
alter database recover managed standby database disconnect using current logfile
*
ERROR at line 1:
ORA-38500: USING CURRENT LOGFILE option not available without stand

Resolution:
1. I created Log Groups and Log Files for Standby Database to try fix this issue and as per my expectations it worked.

Added Three log groups of same size 50MB each on Primary Database for Standby (Log Groups should be always be of same size – What you have on Primary DB, Mine was – 52428800 (50MB)):

SQL>ALTER DATABASE ADD STANDBY LOGFILE GROUP 3 SIZE 50M;
Database Altered

SQL>ALTER DATABASE ADD STANDBY LOGFILE GROUP 4 SIZE 50M;
Database Altered

SQL>ALTER DATABASE ADD STANDBY LOGFILE GROUP 5 SIZE 50M;
Database Altered

SQL> select group#, member, type from v$logfile;

GROUP#         MEMBER                                                                        TYPE
———- ———————————————————————————————————————————–
4       /u01/app/oracle/flash_recovery_area/DOOM/onlinelog/o1_mf_4_88j4601r_.log                      STANDBY
3       /u01/app/oracle/flash_recovery_area/DOOM/onlinelog/o1_mf_3_88j4859l_.log                      STANDBY
5       /u01/app/oracle/flash_recovery_area/DOOM/onlinelog/o1_mf_5_88j4d4t5_.log                      STANDBY

On Standby Database:
2. Added a standby logfile on Std DB end:

SQL> alter database add standby logfile ‘/u01/app/oracle/admin/doom/stdy_log.log’ size 10m;
Database altered.

SQL> alter database recover managed standby database disconnect using current logfile;
Database altered.

SQL> SELECT RECOVERY_MODE FROM V$ARCHIVE_DEST_STATUS WHERE DEST_ID=2 ;
RECOVERY_MODE
———————–
MANAGED REAL TIME APPLY

SQL> select RECOVERY_MODE, DATABASE_MODE, PROTECTION_MODE from v$archive_dest_status;

RECOVERY_MODE           DATABASE_MODE   PROTECTION_MODE
———————– ————— ——————–
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE
MANAGED REAL TIME APPLY MOUNTED-STANDBY MAXIMUM PERFORMANCE

11 rows selected.

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Data Guard – Adding and Resizing a datafile on the Primary database

Posted by FatDBA on October 13, 2012

Standby Database (Data Guard) is slowly and steadily turning out to be my best topic/subject among others in High Availability. It attracts me to experiment to improve the HA features.

Alright, today I’ve fixed one of the problem i was facing from past few days and discovered that i was doing a stupid mistake and that i failed to catch too till the moment i rechecked some parameters in initialization file minute ago.

I tried to add/modify some data files and was not getting at the Standby End which resulted in several errors at Sb DB and lead to Standby Database crash. Otherwise i have to manual port log files from primary destination to the Standby party to maintain the sync between the two after datafiles addition.

Below were the error messages i was getting when tested the standby status:

SQL>  select message from v$dataguard_status;

MESSAGE
——————————————————————————–
ARC0: Archival stopped
ARC1: Archival stopped
Media Recovery Waiting for thread 1 seq# 197

Solution:
I’ve check and found Standby_File_Management was set to ‘MANUAL’
and both the db_file_name_convert and log_file_name_conver were different.

I’ve set all the three parameters to below provided values
Standby_File_Management=AUTO  (Both on Primary and Standby)
db_file_name_convert          ( I’ve left it unchanged on both sides – it was empty (default))
log_file_name_convert         ( I’ve left it unchanged on both sides – it was empty (default))

Snippets from my machine:
SQL> show parameter standby_file_management    (On both Primary and Standby)

NAME                                 TYPE        VALUE
———————————— ———– ——————————
standby_file_management              string      AUTO

SQL> show parameter db_file_name_convert

NAME                                 TYPE        VALUE
———————————— ———– ——————————
db_file_name_convert                 string

SQL> show parameter log_file_name_convert

NAME                                 TYPE        VALUE
———————————— ———– ——————————
log_file_name_convert                string

 

  1. Add a new tablespace to the primary database:
    SQL> CREATE TABLESPACE new_ts DATAFILE '/disk1/oracle/oradata/payroll/t_db2.dbf'
      2> SIZE 1m AUTOEXTEND ON MAXSIZE UNLIMITED;
  2. Archive the current online redo log file so the redo data will be transmitted to and applied on the standby database:
    SQL> ALTER SYSTEM ARCHIVE LOG CURRENT;
  3. Verify the new datafile was added to the primary database:
    SQL> SELECT NAME FROM V$DATAFILE;
    NAME
    ----------------------------------------------------------------------
    /disk1/oracle/oradata/payroll/t_db1.dbf
    /disk1/oracle/oradata/payroll/t_db2.dbf
  4. Verify the new datafile was added to the standby database:
    SQL> SELECT NAME FROM V$DATAFILE;
    NAME
    ----------------------------------------------------------------------
    /disk1/oracle/oradata/payroll/s2t_db1.dbf
    /disk1/oracle/oradata/payroll/s2t_db2.dbf

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Database Links Explained ?

Posted by FatDBA on October 7, 2012

Database Links are objects which we create to establish a connection from one database to another. They are classified in to three parts:

1. Private Database Links: Belongs to specific schema. Only the owner of the link can use it and is default DB link type.
2. Public Database Links: Belongs to all users exists in Database.
3. Global database link – Defined in an OID or Oracle Names Server. Anyone on the network can use it.
Conditions:
1. User should have Privilege ‘CREATE DATABASE LINK’.

Format:
Create Database Link <DB Link> connect to < User > identified by < Password > using < Service Name >;
OR
Create Public Database Link <DB Link> connect to < User > identified by < Password > using < Service Name >;

Example:

Create Database Link <DB Link Name> connect to < User > identified by < Password > using < Service Name >;
SQL> create database link larry1 connect to larry identified by oracle90 using ‘ORCL’;
Database link created.

SQL> select * from dual@larry1;

D

X

SQL> update etr@larry1 set ID=7  where NAME=’prashant’ and TEAM=’cis’;

1 row updated.

SQL> select * from etr@larry1;

NAME         TEAM       ID
———— ———- —
prashant     cis        7
shantanu     cis        12
saurabh      oracle     19
ram          helpdesk   3
prashant     unix       5
tondu        security   1
amit         qa

7 rows selected.

Posted in Basics | 1 Comment »

What is Yum in Linux and how to configure ?

Posted by FatDBA on October 1, 2012

Why to use: Many times while installing Database on Linux/Linux most of us encounters problems with the pre-installations which requires some of the Packages to be available to Oracle before the installation starts.  Searching required RPM’s online is a tedious job and needs lot of patience which could ultimately lead to errors about “Dependencies Failed”.  A best resolution of this problem is YUM, which resolves dependency part by itself  and allow the package search and install easily from the repository created.

The Yellow dog Updater Modified (YUM) is a package management application for computers running Linux operating systems. yum is a standard method of managing the installation and removal of software.

Steps to Configure YUM Repository on RED HAT:

1) Install vsftpd (FTP Server) & createrepo Packages
Insert RHEL 5 Installation DVD

# mkdir ~/Desktop/rhel_cd
# mount /dev/cdrom ~/Desktop/rhel_cd
# cd ~/Desktop/rhel_cd/Server
# rpm –ivh vsftpd*
# rpm –ivh createrepo*

2) Copy all packages from DVD to LINUX filesystem

# cp ~/Desktop/rhel_cd/Server/ /var/ftp/pub
# cd /
# eject

3) Configure Local Yum Repository Server

# cd /var/ftp/pub/Server/repodata
# cp comps-rhel5-server-core.xml /var/ftp/pub/Server/
# cd /var/ftp/pub/Server
# createrepo -vg comps-rhel5-server-core.xml /var/ftp/pub/Server/
# service vsftpd start
# chkconfig –add vsftpd

4) Configure Clients
Run following commands on clients

# vi /etc/yum.repos.d/yum_server.repo

Add:
[Server]
name=YUM_SERVER
baseurl=ftp://192.168.2.100/pub/Server
gpgcheck=0

# vi /etc/vsftpd/vsftpd.conf

Set the following parameter (if not already set)
anonymous_enable = yes

# service vsftpd restart

Now your clients can use this yum server to download & install packages & resolve
dependencies.

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