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

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 

or

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.

Install Oracle Data Modeler 4.0 on Ubuntu 14.04

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

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!

Install the Microsoft Core fonts

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

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

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

Install Nvidia drivers on CentOS 6 and RHEL 6

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