Oracle Noob

Scan and Add SAN disks in Linux (Redhat & Centos) without reboot

2014-06-15T20:30:00.000+02:00

This small guide will try to explain how to scan and add SAN disks to a Centos / Redhat server. To detect new disks that been added (zoned) to the server run the following commands.

for i in `seq 0 10`; do echo 1 > /sys/class/scsi_device/device$i/scan; done
for i in `seq 0 10`; do echo "- - -" > /sys/class/scsi_host/host$i/scan; done

The commands will loop thru all scsi_devices and activate a rescan. Note: if scsi_host does not exists, use fc_host instead.

If you have the sg3_utils package installed you can run this instead:

/usr/bin/rescan-scsi-bus.sh -l

But then LUN0 must be the first mapped logical unit for it to work.

To see the newly scanned disks run:

lsscsi

fdisk -l

If you are using multipath i also recommend you to run this to force a devmap reload:

multipath -r

Check that the new disks shows up with:

multipath -l

Now we can proceed with creating a LVM volume on those disks.

Show locks in a Netezza Database

2014-06-15T19:43:00.000+02:00

This SQL statement when run in Aginity or nzsql will show you all sessions that cause locks in a database.

select sessionid, 
       clientip,
       username, 
       relname as table_name, 
       requesttime as lock_request_time,
       granttime as lock_acquired_time, 
       command as sql, 
       lockstate  
from _t_pg_locks 
where relid in ( select relid from _t_pg_locks where lockstate='WAIT') 
order by requesttime, granttime

To kill a session / transaction you can simply right click it under current sessions in Netezza Administrator.

Unlock APEX admin user (when apxchpwd.sql doesn't work)

2014-05-26T22:55:00.000+02:00

First we need to find the Apex admin accounts user_id. We do that with the following statement.
You might have two. Mine was the second one

select user_id from APEX_040200.WWV_FLOW_FND_USER where user_name = 'ADMIN' order by last_update_date desc;

Set a new password for the Apex Admin with the user_id we selected.

update APEX_040200.WWV_FLOW_FND_USER
set web_password = 'password'
where user_name = 'ADMIN'
and user_id = 56502607595642;
commit;

Then we unlock the Admin account with this statement.

alter session set current_schema = APEX_040200;
begin
wwv_flow_security.g_security_group_id := 10;
wwv_flow_fnd_user_api.UNLOCK_ACCOUNT('ADMIN');
commit;
end;

Install Oracle Data Modeler 4.0 on Ubuntu 14.04

2014-01-11T22:53:00.000+01:00

This little HOW-TO will explain how to install Oracle's Data Modeler 4.0 on Ubuntu 14.04
First download the Oracle Data Modeler 4 rpm from Oracle's website http://www.oracle.com

Install alien to be able to convert .rpm packages to .deb

sudo apt-get install alien

Convert and install the Data Modeler 4 .rpm
This way you will be able to link the program on the launcher

sudo alien --scripts datamodeler-4.0.*.rpm 
sudo dpkg -i datamodeler_4.0.*.deb

Fix an install bug and the startscript for Data Modeler so it won't crash on startup
Edit /usr/local/bin/datamodeler and add:
unset -v GNOME_DESKTOP_SESSION_ID to the first line in the start script.

sudo touch /opt/datamodeler/datamodeler/types/defaultdomains.xml
sudo chown username.username /opt/datamodeler/datamodeler/types/defaultdomains.xml
sudo vi /usr/local/bin/datamodeler

Done! Now you can find and start it in unity!

Install Oracle SQL Developer 4.0 on Ubuntu 14.04

2014-01-11T22:25:00.000+01:00

This little HOW-TO will explain how to install Oracle's SQL Developer 4.0 on Ubuntu 14.04
First download the Oracle SQL developer 4 rpm from Oracle's website http://www.oracle.com

Install alien to be able to convert .rpm packages to .deb

sudo apt-get install alien

Convert and install the SQL developer 4 .rpm
This way you will be able to link the program on the launcher

sudo alien --scripts sqldeveloper-4.0.*.noarch.rpm 
sudo dpkg -i sqldeveloper_4.0.*.deb

Fix the startscript for SQL developer so it won't crash on startup
Edit /usr/local/bin/sqldeveloper and add:
unset -v GNOME_DESKTOP_SESSION_ID to the first line in the start script.

sudo vi /usr/local/bin/sqldeveloper

Done! Now you can find and start it in unity!

Enable RPMforge repository

2011-10-16T16:18:00.000+02:00

These few commands will help you add the RPMforge repository on your system.
They have alot of good and useful rpms that are often needed.

Open a terminal

su - root
rpm -ivh http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm
yum update

Done!

Install the Microsoft Core fonts

2011-10-16T14:20:00.001+02:00

This HOW-TO will show you how to install the Microsoft Core Fonts.
These steps will download build and install an rpm with the mscorefonts.
Open a terminal

su - root
cd ~
yum install chkfontpath rpm-build cabextract
mkdir rpmbuild
cd rpmbuild
wget http://corefonts.sourceforge.net/msttcorefonts-2.0-1.spec
rpmbuild -bb msttcorefonts-2.0-1.spec 
rpm -ivh RPMS/noarch/msttcorefonts-2.0-1.noarch.rpm

List current active users, sessions and programs in Oracle 11g

2011-10-15T18:16:00.000+02:00

List current users, sessions and programs
(not background processes)

SELECT username, sid, serial#, program
FROM v$session
WHERE username is NOT NULL
ORDER BY logon_time;

Remove there WHERE clause if you want to include all background processes like pmon.

Install the EPEL repository on CentOS 6, Oracle Linux and RHEL 6

2011-10-15T14:45:00.001+02:00

This little HOW-TO shows you how to enable the fedora EPEL repository on the 64 bit version of CentOS 6, Oracle Linux 6 and Red Hat Enterprise Linux 6 (x86_64)
It contains a lot of useful packages and software that you wont have access to otherwise

Add the EPEL repository from the fedora project
Open a terminal and become root

su - root
rpm -Uvh http://download.fedora.redhat.com/pub/epel/6/x86_64/epel-release-6-5.noarch.rpm

Thats it!

How to enable Media playback on CentOS, Oracle Linux and RHEL 6

2011-10-15T14:33:00.000+02:00

This HOW-TO will go thru the process of enabling multimedia like DivX, WMV and other codecs
(or MPlayer and its codecs) on CentOS 6 and other Enterprise Linux versions (like Oracle and Red Hat)

First make sure you have the ATrpms and RPMforge repositories enabled.
If you like Media player in gnome (based on totem and gstreamer) Then just install the 2 packages below. Otherwise see the Mplayer install.

Install plugins for gnome default media player
Open a terminal

yum install gstreamer-ffmpeg gstreamer-plugins-ugly gstreamer-plugins-bad libmms

Thats it! Now you can play almost everything.
If you feel that its not enough, then install MPlayer too.

Install Mplayer

su - root
yum install ffmpeg libdvdcss libdvdread libdvdnav lsdvd mplayer gnome-mplayer

# Then download the lastest complete codec pack. (This was the latest at the time)
cd ~
wget http://www.mplayerhq.hu/MPlayer/releases/codecs/all-20110131.tar.bz2
tar -jxvf all-20110131.tar.bz2
cd all-20110131

# Create the codecs directory and copy the plugins there.
mkdir /usr/lib/codecs
cp * /usr/lib/codecs

Now you should have GNOME-Mplayer under Sound & Video in the start menu.
Enjoy!

How to add the ATrpms repository on CentOS 6, Oracle Linux 6 and RHEL 6

2011-10-15T13:33:00.005+02:00

ATrpms have few but very good rpms
I use them to enable media playback on my desktop systems.

Open a terminal

# Become root
su - root

# Import the GPG key for ATrpms
rpm --import http://packages.atrpms.net/RPM-GPG-KEY.atrpms

# Open an editor
vi /etc/yum.repos.d/atrpms-stable.repo

# Paste this into the atrpms-stable.repo file    
[atrpms-stable]
name=RHEL 6 - atrpms-stable - $releasever - $basearch 
baseurl=http://dl.atrpms.net/el6-$basearch/atrpms/stable/
gpgcheck=1
enabled=1
priority=3
exclude=*release

# Update YUM
yum update

Done!

Install Symbol Browser plugin for Gedit on Centos 6

2011-10-15T13:12:00.000+02:00

HOW-TO install the Symbol Browser plugin for Gedit 2.28.4 (default for Centos 6)
You might need to install some more dependencies depending of your type of CentOS install.
(./configre will report what you are missing)

Open a terminal

# FIX DEPENDENCIES 
    su - root
    yum install enchant-aspell enchant-develiso-codes-devel    
    exit

# DOWNLOAD AND EXTRACT SOURCES
    cd ~
    wget http://ftp.acc.umu.se/pub/gnome/sources/gedit/2.28/gedit-2.28.4.tar.gz
    tar -xzf gedit-2.28.4.tar.gz
    cd gedit-2.28.4
    cd plugins
    wget http://sourceforge.net/projects/symbol-browser/files/symbol-browser/gedit-symbol-browser-plugin/gedit-symbol-browser-plugin-0.1.tar.gz
    tar -xzf gedit-symbol-browser-plugin-0.1.tar.gz

# EDIT MAKE AND CONFIGURE FILES
    sed -i 's/SUBDIRS =/SUBDIRS = \t\\\n\tsymbolbrowser\t/g' Makefile.am
    sed -i 's/DIST_SUBDIRS =/DIST_SUBDIRS =\t\\\n\tsymbolbrowser\t/g' Makefile.am
    cd ..
    sed -i 's/AC_CONFIG_FILES(\[/AC_CONFIG_FILES(\[\nplugins\/symbolbrowser\/Makefile/g' configure.ac

# BUILD THE PLUGIN
    autoconf
    automake
    ./configure
    cd plugins/symbolbrowser
    make

# COPY TO HOME FOLDER 
    cp symbolbrowser.gedit-plugin .libs/libsymbolbrowser.so ~/.gnome2/gedit/plugins/
    cp -r symbols ~/.gnome2/gedit/

Install Oracle 11gR2 XE on Centos 6, Oracle Linux 6, RHEL 6

2011-10-12T21:56:00.003+02:00

This little HOW-TO shows you how download and install the 64 bit version of Oracle 11gR2 XE APEX
on CentOS 6, Oracle Linux 6 and Red Hat Enterprise Linux 6 (x86_64)

Download Oracle 11gR2 XE from www.oracle.com
Open a terminal and become root, then go to the folder you downloaded the file to.

su - root
unzip oracle-xe-11.2.0-1.0.x86_64.rpm.zip
cd Disk1
rpm -Uvh oracle-xe-11.2.0-1.0.x86_64.rpm
/etc/init.d/oracle-xe configure

Thats it!

You can now stop and start the database with:

/etc/init.d/oracle-xe stop
/etc/init.d/oracle-xe start

You might also want to add the oracle binaries in your $PATH so you can access sqlplus, rman and other commands.
Open a terminal and become root. Then cut n' paste the script below into:
/etc/profile.d/oracle.sh

su - root
vi /etc/profile.d/oracle.sh

Enter this script:

if ! echo ${PATH} | /bin/grep -q /u01/app/oracle/product/11.2.0/xe/bin ; then
PATH=/u01/app/oracle/product/11.2.0/xe/bin:${PATH}
fi

Save it, then close the terminal and open a new one for the change to take effect.
To access the webgui and/or apex:
Go go http://localhost:8080

How to get command-line history in SQL*PLUS with rlwrap

2011-10-12T21:05:00.007+02:00

sql*plus does not have a command-line history function under Linux and Unix.
rlwrap is a readline wrapper for shell commands which uses input from the controlling terminal.
It adds a persistent input history for each command and supports user-defined completion.

You can install it via yum if you have enabled the EPEL repository.
Or you can download the sources from here
Then open a terminal and go to the catalog you downloaded it to

If you have the EPEL repository enabled
Open a terminal

su - root
yum install rlwrap

Otherwise you do like this. Again in the folder you downloaded the file to.
Open a terminal

su - root
tar -zxvf rlwrap-0.37.tar.gz
./configure
make
make install

Now you can call sqlplus like this:

rlwrap sqlplus user/password@sid

I also recommend creating an alias like this

alias sqlp =”rlwrap sqlplus”

Now you can start the wrapped sqlplus with sqlp and have command history with the ↑ and ↓ keys on your keyboard.

Install Oracle Java 6 JDK on CentOS 6 and RHEL 6

2011-10-09T21:54:00.008+02:00

This little HOW-TO shows you how install Oracle's Java 6 JDK on the 64 bit version of CentOS 6 and Red Hat Enterprise Linux 6 (x86_64) and how to configure your system and browser to use this faster java.

Install Java6 JDK
Download it from Oracle's website www.oracle.com and make it executable

wget http://download.oracle.com/otn-pub/java/jdk/6u27-b07/jdk-6u27-linux-x64-rpm.bin
chmod u+x jdk-6u27-linux-x64-rpm.bin
./jdk-6u27-linux-x64-rpm.bin

Make our system and browsers use our new java

/usr/sbin/alternatives --install /usr/bin/java java /usr/java/default/bin/java 20000 
/usr/sbin/alternatives --install /usr/lib/mozilla/plugins/libjavaplugin.so libjavaplugin.so /usr/java/default/jre/lib/i386/libnpjp2.so 20000

Install Adobe flash plugin on CentOS 6 and RHEL 6

2011-10-09T21:28:00.005+02:00

This little HOW-TO shows you how install the Adobe flash plugin on the 64 bit version of CentOS 6 and Red Hat Enterprise Linux 6 (x86_64)
by using Adobe's own YUM repository. This way you will get easy updates!

Install Adobe FLASH plugin
Download the rpm from http://get.adobe.com/flashplayer/otherversions/ and select Linux 64bit and flashplayer 11 for other linux (YUM)
Go to download folder (for the user that downloaded the files)

su - root
cd /home/yourusername/Downloads
rpm -ivh adobe-release-x86_64-1.0-1.noarch.rpm
yum install flash-plugin

Restart your browser

Install Nvidia drivers on CentOS 6 and RHEL 6

2011-10-09T21:09:00.002+02:00

This little HOW-TO shows you how to disable nouveau and install the Nvidia drivers on the 64 bit version of CentOS 6 and Red Hat Enterprise Linux 6 (x86_64)

Add ELrepo repository and key
Open a terminal and become root

su - root
rpm --import http://elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvh http://elrepo.org/elrepo-release-6-4.el6.elrepo.noarch.rpm

Install NVIDIA drivers and blacklist nouveau
Edit /etc/grub.conf and add nomodeset rdblacklist=nouveau at the end of the kernel line

su - root
echo "blacklist nouveau options nouveau modeset=0" > /etc/modprobe.d/blacklist-nouveau.conf
yum install kmod-nvidia
vi /etc/grub.conf

Add nomodeset rdblacklist=nouveau at the end of the kernel line
Restart your machine