Notes for installing Oracle Database...
Preinstall
Oracle provides an RPM package to install dependencies required by the database. This will tune the system, create an 'oracle' user and install Xorg libraries needed for the 'graphical' installer.
For RHEL / CentOS, etc. you can find it on Oracle's yum server:
To install the RPM, type the appropriate 'yum' (aka 'dnf') command:
Example:
sudo yum install oracle-database-preinstall-21c
Update User Privileges (Optional)
The Oracle Database Preinstall will create an 'oracle' user. Here are some optional steps to making your life easier.
Give the 'oracle' user a password...
# passwd oracle
Add 'oracle' to the 'wheel' group, so it can use 'sudo'...
# usermod -aG wheel oracle
Use the command 'visudo' to edit the sudo properties to allow the 'wheel' group to run commands without a password.
## Allows people in group wheel to run all commands
#%wheel ALL=(ALL) ALL
## Same thing without a password
%wheel ALL=(ALL) NOPASSWD: ALL
Configure SELinux
Set SELinux to "permissive".
sudo sed -i 's/SELINUX=enforcing/SELINUX=permissive/g' /etc/selinux/config
sudo setenforce Permissive
Configure Firewall
Let's open necessary ports in the firewall.
sudo firewall-cmd --permanent --add-service=https
sudo firewall-cmd --permanent --add-service=snmp
sudo firewall-cmd --permanent --add-port=1521/tcp
sudo firewall-cmd --permanent --add-port=5500/tcp
sudo systemctl restart firewalld
Choose Installation Type
Oracle offers three types of installation: graphical, silent and rpm.
Graphical is the traditional installation option, but requires a working XOrg (X-Windows) connection.
Silent will run without X-Windows, but requires an input script.
RPM can be installed via YUM / DNF but makes many assumptions that may need to be altered in the future.
Choose your preferred method to continue: