Oracle XE 21c on Centos 8

Why XE 21c?
For development or small sites, 21c is a great way to test the waters with Oracle. As per the press release - "You get an Oracle Database to use in any environment, plus the ability to embed and redistribute – all completely free!"

Features:

• 2 CPU threads
• 2 GB of RAM
• 12GB of user data
• Supports Pluggable databases

Resources:

• Press Release.
• Quick Start Guide

Create a host
For my purposes I created a Digital Ocean droplet.

• CentOS 8 Stream x64
• Basic, 2CPU, 2GB, 60GB, regular SSD is $15/mo
• Select Data Center central to your usual user activity, NYC3 for me
• Select preferred login method (password or SSH key)

Harden host
Initial Server Setup with Centos 8

Upon first login:

# Install utilities and get image packages current
 yum install wget
 yum -y update

Install Oracle XE 21c

# Download and install Pre-Install .rpm
wget https://yum.oracle.com/repo/OracleLinux/OL8/appstream/x86_64/getPackage/oracle-database-preinstall-21c-1.0-1.el8.x86_64.rpm
yum -y install oracle-database-preinstall-21c-1.0-1.el8.x86_64.rpm

# Download and install RDBMS .rpm
wget https://download.oracle.com/otn-pub/otn_software/db-express/oracle-database-xe-21c-1.0-1.ol8.x86_64.rpm
yum -y install oracle-database-xe*

Create database

/etc/init.d/oracle-xe-21c configure

Enter password ( Oracle1234 for low security test systems )
Post DB Creation

• Default PDB created is XEPDB1
• Sys/system/pdbsys passwords were set above in configure script, add them to your Password Vault!

100% complete
Database creation complete. For details check the logfiles at:
 /opt/oracle/cfgtoollogs/dbca/XE.
Database Information:
Global Database Name:XE
System Identifier(SID):XE
Look at the log file "/opt/oracle/cfgtoollogs/dbca/XE/XE.log" for further details.

Connect to Oracle Database using one of the connect strings:
     Pluggable database: localhost.localdomain/XEPDB1
     Multitenant container database: localhost.localdomain
Use https://localhost:5500/em to access Oracle Enterprise Manager for Oracle Database XE

Set DB to autostart as root:

systemctl daemon-reload
systemctl enable oracle-xe-21c

Config updates:

alter system set db_create_file_dest='/opt/oracle/oradata' scope=both sid='*';
drop pluggable database XEPDB1 including datafiles;

create pluggable database apexdev admin user pdbsys identified by Oracle1234;
create pluggable database apextst admin user pdbsys identified by Oracle1234;
create pluggable database apexprd admin user pdbsys identified by Oracle1234;

alter pluggable database apexdev open;
alter pluggable database apextst open;
alter pluggable database apexprd open;

alter pluggable database apexdev save state;
alter pluggable database apextst save state;
alter pluggable database apexprd save state;

Firewall

firewall-cmd --zone=public --add-port=1521/tcp