Oracle Cloud Infrastructure Documentation

Getting Started with Oracle Linux

Oracle Cloud Infrastructure has a set of Oracle Linux platform images that you can select when creating an instance.

For more information about Oracle Linux platform images, see Platform Images. For information about specific releases of platform images, see Release Information.

Key features for Oracle Linux on Oracle Cloud Infrastructure

Oracle Linux images available on Oracle Cloud Infrastructure include:

The advantages of Oracle Cloud Infrastructure Oracle Linux images over traditional Oracle Linux deployments are:

  • Instances automatically have access to Unbreakable Linux Network (ULN) content.

    • If the instance is connected to a service gateway, it has access to ULN content through the regional yum servers. Unlike the publicly available Oracle Linux yum server, the Oracle Cloud Infrastructure regional yum servers mirror all ULN channels. Thus, you can access ULN content without registering the system with ULN or using alternate tools to manage channel access, which simplifies software management on the instance.

  • All images have Oracle Ksplice installed by default.

    • You can run Ksplice to install patches manually or enable automatic updates to get the latest security patches without any need to reboot.

  • The default kernel is the latest version Unbreakable Enterprise Kernel (UEK) available for the image.

    • Setting the default kernel to UEK ensures the broadest functionality support immediately after deploying an instance.

  • Instances can use the OCI Utilities.

    • The OCI utilities are a set of custom tools that allow the instance to access information about infrastructure resources. These tools can help automatically discover or provision resources as you need them.

Creating an Instance

Create a Linux instance using the Embedded Marketplace, Oracle Images tab, or Oracle Cloud Marketplace.

Using the Embedded Marketplace

  1. Log in to the Oracle Cloud Infrastructure Console.

  2. Open the navigation menu and click Marketplace, then, under Marketplace, click All Applications.

  3. In the search box, type the name of the image. Options include:

  4. Press Enter and then select the image.

  5. Launch the instance:

    1. Select the Version of the image and the Compartment.

    2. Review and then accept the Oracle standard Terms and Restrictions.

    3. Click Launch Instance.

  6. Enter the Name, select the compartment from Create in compartment, and in the Placement section, select the Availability domain.

    You can add or change the name later. The name does not need to be unique, because an Oracle Cloud Identifier (OCID) uniquely identifies the instance.

  7. Optional: Change the instance type or the instance shape:

    1. Click Change Shape.

      The Browse all shapes window is displayed.

    2. Choose an Instance type of Virtual Machine or Bare metal machine.

    3. If displayed, select a compute Shape Series on which to deploy the image.

    4. Select the Shape name.

      The service limits status is displayed for the selected shape. You can optionally choose to request a service limit increase by clicking Request increase, or view the current service limits of the shape by clicking View limits.

    5. Click Select Shape.

  8. Under the Primary VNIC information and Primary VNIC IP addresses sections, make any necessary changes to the default settings.

  9. Under Add SSH keys, either generate a key pair or upload your own public key.

    If you provide an existing public key, then when you connect to the instance, you are prompted to also provide the associated private key. For more information about SSH keys, see Managing Key Pairs on Linux Instances.

  10. Under Boot volume, change the default boot volume size or encrypt the volume.

  11. Click Create to deploy your instance.

Using the Oracle Images Tab

  1. Log in to the Oracle Cloud Infrastructure Console.

  2. Open the navigation menu and click Compute, then, under Compute, click Instances.

  3. Click Create Instance.

  4. Enter the Name, select the compartment from Create in compartment, and in the Placement section, select the Availability domain.

    You can add or change the name later. The name does not need to be unique, because an Oracle Cloud Identifier (OCID) uniquely identifies the instance.

  5. Within the Image and Shape section, click Change Image.

    The Select an image window is displayed.

  6. From the Select an image window, click Oracle Linux as the type of image, and from the Image Name list, choose the name of the image. Options include:

  7. Optionally click View compatible shapes to see the shapes that are compatible with the image.

  8. Click Select Image.

    The Select an image window is closed.

  9. Optional: Change the instance type or the instance shape:

    1. Click Change Shape.

      The Browse all shapes window is displayed.

    2. Choose an Instance type of Virtual Machine or Bare metal machine.

    3. If displayed, select a compute Shape Series on which to deploy the image.

    4. Select the Shape name.

      The service limits status is displayed for the selected shape. You can optionally choose to request a service limit increase by clicking Request increase, or view the current service limits of the shape by clicking View limits.

    5. Click Select Shape.

  10. Under the Primary VNIC information and Primary VNIC IP addresses sections, make any necessary changes to the default settings.

  11. Under Add SSH keys, either generate a key pair or upload your own public key.

    If you provide an existing public key, then when you connect to the instance, you are prompted to also provide the associated private key. For more information about SSH keys, see Managing Key Pairs on Linux Instances.

  12. Under Boot volume, change the default boot volume size or encrypt the volume.

  13. Click Create to deploy your instance.

Using the Oracle Cloud Marketplace

The Oracle Cloud Marketplace is outside of Oracle Cloud Infrastructure. For more information, see Overview of Marketplace.

  1. Go to the Oracle Cloud Marketplace.

  2. In the search box, type the name of the image. Options include:

  3. Select the image version. Click Get App.

  4. Log into your Oracle Cloud Infrastructure Account.

  5. Launch the instance:

    1. Select the Version of the image and the Compartment.

    2. Review and then accept the Oracle standard Terms and Restrictions.

    3. Click Launch Instance.

  6. Enter the Name, select the compartment from Create in compartment, and in the Placement section, select the Availability domain.

    You can add or change the name later. The name does not need to be unique, because an Oracle Cloud Identifier (OCID) uniquely identifies the instance.

  7. Optional: Change the instance type or the instance shape:

    1. Click Change Shape.

      The Browse all shapes window is displayed.

    2. Choose an Instance type of Virtual Machine or Bare metal machine.

    3. If displayed, select a compute Shape Series on which to deploy the image.

    4. Select the Shape name.

      The service limits status is displayed for the selected shape. You can optionally choose to request a service limit increase by clicking Request increase, or view the current service limits of the shape by clicking View limits.

    5. Click Select Shape.

  8. Under the Primary VNIC information and Primary VNIC IP addresses sections, make any necessary changes to the default settings.

  9. Under Add SSH keys, either generate a key pair or upload your own public key.

    If you provide an existing public key, then when you connect to the instance, you are prompted to also provide the associated private key. For more information about SSH keys, see Managing Key Pairs on Linux Instances.

  10. Under Boot volume, change the default boot volume size or encrypt the volume.

  11. Click Create to deploy your instance.

For more information, see Creating a Compute Instance.

Accessing an Instance

Connect to your Oracle Cloud Infrastructure instance using SSH.

Prerequisites

Before connecting, obtain the following:

  • SSH client
  • Public IP address of the instance
  • Path to the SSH-2 RSA private key file

Connecting Using SSH

  1. Complete the Prerequisites.
  2. From an SSH client, use the default opc user to connect to the instance.

    For example:

    ssh -i PRIVATE_KEY_PATH opc@PUBLIC_IP_ADDRESS
  3. After you’re logged in as opc, you can use the sudo command to run administrative tasks.

    For example, run the following command to show details for all storage devices attached to your instance:

    sudo oci-iscsi-config --show

For more information, see:

Installing Software

Install software by enabling repositories from the Oracle Cloud Infrastructure regional yum servers.

Unlike the publicly available Oracle Linux yum server, the Oracle Cloud Infrastructure regional yum servers mirror all ULN channels. Therefore, compute instances can access ULN content without having to register the system with ULN. For more information, see:

Connecting to the Regional Yum Server

Instances connected to the service gateway automatically have access to the regional yum servers. The $ociregion and $ocidomain yum variables determine which regional server the instance connects to.

For example, the baseurl to the _latest repository for Oracle Linux 8 is: 

baseurl=https://yum$ociregion.$ocidomain/repo/OracleLinux/OL8/baseos/latest/$basearch/

  • Set the $ociregion variable by populating content in /etc/yum/vars/ociregion.

    If the ociregion file does not exist or is empty, the baseurl points to the publicly accessible Oracle Linux yum server. Typically, when you create the instance the $ociregion variable is set to point to the closest regional yum server on the Oracle Cloud Infrastructure service network. For example, if $ociregion is set to -phx, the baseurl expands to point to the regional yum server in Phoenix.

  • Set the $ocidomain variable by populating content in /etc/yum/vars/ocidomain.

Accessing ULN Content

To access ULN content on the regional yum servers, install the appropriate release-elx packages and enable the repositories that you require access to.

For example, on Oracle Linux 8, you can run the following commands to access the ol8_oci_included repository, where tools like Oracle InstantClient, the Oracle Java Development Kit and Oracle Java Runtime Environment are located: 

sudo dnf install oci-included-release-el8
sudo dnf config-manager --enable ol8_oci_included

Other ULN channels are also available directly through the Oracle Cloud Infrastructure regional yum servers. For example, to access the Ksplice channels on an Oracle Linux 8 compute instance, you can do: 

sudo yum install ksplice-release-el8
sudo yum-config-manager --enablerepo ol8_ksplice ol8_x86_64_userspace_ksplice

Most of these channels are installed and available by default in the latest platform images.

Using OS Management Hub

You can use OS Management Hub to manage packages on Oracle Linux instances, including installing, removing, and updating packages. See Oracle Linux Package Management for more information.

OS Management Hub uses software sources to provide packages to instances, and to track the available updates to those packages. A software source is a collection of packages. Software sources enable you to control which packages can be installed on instances without having to manually log in and configure the repositories on each instance. See Managing Software Sources for more information.

Updating an Instance

Use Oracle Ksplice, OS Management Hub, or Oracle Autonomous Linux to help automate system updates, but also follow recommended guidance to keep your system up to date.

Using Oracle Ksplice

You can use Oracle Ksplice to patch a system without requiring a reboot. However, these updates only occur in-memory. You must also update packages on-disk to their latest versions, so that when the system reboots, it starts from the most current release. Follow the recommendations in Maintaining the System.

Using Autonomous Linux

Autonomous Linux can automatically handle system package updates on a regular schedule. Autonomous Linux provides automatic daily updates in addition to the zero-downtime Ksplice updates for kernel, OpenSSL, and glibc libraries. These updates are referred to as autonomous updates. When you create an Autonomous Linux instance, the service automatically creates a controlled scheduled job for autonomous updates. You can update the start time for the daily autonomous updates using the Console, CLI, or API.

Maintaining the System

Regularly update the operating system and user space packages to obtain the latest bug fixes and security patches.

Oracle recommends that you:

  1. Subscribe the instance to the _latest yum repository for your Oracle Linux release.

  2. Update any software that was installed outside of the Oracle Linux yum package manager.

    For example, tools such as flatpak and snap, for installing desktop applications; and pip, gem and npm, for installing Python, Ruby and Node libraries and modules, all have their own software update mechanisms.

  3. Always update instances to the most recent release of the operating system.

    Oracle Linux uses a rolling update level approach for keeping software up to date. For example, Oracle Linux 8.4 or Oracle Linux 8 Update 4, are rolling snapshots of the latest supported packages for the Oracle Linux release and are not considered independent versions of Oracle Linux.

  4. Manually update packages or install and configure the appropriate tool for automatic updates.

Adding Users and Groups

Use the default opc user to add users and groups to a newly created instance.

Oracle recommends that you create and configure users and groups according to your access requirements. Access the instance as the opc user (see Accessing an Instance), and then add users and groups as necessary. See Create users and groups on Oracle Linux for a general introduction to users and groups on Oracle Linux.

What is the opc user?

Oracle Linux instances have a default opc user. Use this account to create and configure additional users and groups.

The opc account has:

  • Full sudo privileges.

  • No password configured.

    Instead you access the account over SSH with a key pair configured when you create the instance (see Accessing an Instance).

Adding a User

To add a user named alice to the system:

sudo useradd alice

To set a password for the user:

sudo passwd alice

Adding a Group

To add a group called staff to the system:

sudo groupadd staff

To add the user alice to the group staff:

sudo usermod -G staff alice

Manage the users in a group using the groupmems command. For example, to remove alice from the group staff:

sudo groupmems -d alice -g staff

Configuring Permissions

Define permissions by configuring users and groups within /etc/sudoers.

By default, members of the wheel group can use sudo to obtain all root privileges. You can add entries for users or groups by adding files to /etc/sudoers.d. For example, the privileges assigned to the opc user are defined in /etc/sudoers.d/90-cloud-init-users.

Migrating to Oracle Cloud Infrastructure

You can migrate on-premises Oracle Linux images to Oracle Cloud Infrastructure with the oci-image-migrate utilities. See OCI Image Migrate Utilities.

Oracle Linux Learning Resources

Use these resources to learn more about Oracle Linux.

General Oracle Linux Documentation
The general Oracle Linux documentation is not specific to Oracle Cloud Infrastructure but most of the content still applies.
Training Resources

Use the following Oracle Linux training resources to grow your skill set using free videos and hands-on tutorials and labs.

Blogs and Community Forums
Use these resources to track features highlighted by Oracle or to reach other community users for more help and information.