Centos OS 7 + Oracle XE 21c Instructions of Installation

How to create a virtual machine (VM) with the Centos OS 7 template

Select, mark or enter:

  1. VM Name - create your VM name ;
  2. Hold - check the box;
  3. Memory - 4 GB;
  4. CPU - 2
  5. VCPU - 4
  6. centos7 - 20 GB

Open the virtual machine which you created:

  1. Add 1521 to TCP_PORT_FORWARDING 22;
  2. Expand the 5th function selection icon in the top menu bar on the right, and press Release;
  3. Wait for it to load.

Launch the Putty app and add your private key. More about Putty and private keys read here

Copy the login credentials from the server control panel CONNECT_INFO1. In Putty app enter the SSH key keyword as shown in the example and press Open.

On the command line, write the commands in order. Sometimes you will need to press “y “. You must wait until the command you have previously typed has been executed before typing another command. 

  sudo yum check-update
  sudo yum update
  sudo yum localinstall https://drive.mif.vu.lt/s/T4Z9WxzDgoDqoey/download/oracle-database-preinstall-21c-1.0-1.el7.x86_64.rpm
  sudo yum localinstall https://drive.mif.vu.lt/s/swmrJSjMsfjP5Ax/download/oracle-database-xe-21c-1.0-1.ol7.x86_64.rpm

After the installation, which may take some time, you need to enter the configuration command, set the password and wait for the configuration to finish. 

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

How to connect to the Oracle database

Register and download SQL DEVELOPER. Unzip the files and run the application.

At the top right with the right mouse button, click on Oracle Connections and select New Connection. In the window that appears, in the appropriate fields, type:

  1. Name - session title.
  2. Username - the first time you log in, the SYSTEM user is active, others can be created later.
  3. Password - the one you set during installation.
  4. Hostname - the external IP address that has been assigned.
  5. Port - port attributed by the OPEN NEBULA. You will find it in the main server panel, next to the 1521 you entered.

NOTE: If no new users can be created, enter alter session set “_ORACLE_SCRIPT”=true;