> For the complete documentation index, see [llms.txt](https://docs.ovaledge.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ovaledge.com/deployment-and-maintenance/installation/java21-installation-on-rhel.md).

# Java21 Installation on RHEL

This article describes the steps required to install Java 21 (OpenJDK) on a Red Hat Enterprise Linux (RHEL) system. The procedure ensures that the required Java runtime is installed and verified for use with OvalEdge components.

The steps apply to RHEL 7, RHEL 8, and RHEL 9 environments with minor variations in package management commands.

## Prerequisites

Ensure the following before proceeding:

* Access to a RHEL 7, RHEL 8, or RHEL 9 machine
* Root or sudo privileges
* Internet connectivity to download packages from repositories

## Steps Involved

1. Update System Packages
   * Run the appropriate command to update system packages:
     * For RHEL 8 and RHEL 9:

       ```
       sudo dnf update -y
       ```
     * For RHEL 7:

       ```
       sudo yum update -y
       ```
2. Install Java 21 (OpenJDK)
   * For RHEL 8 and RHEL 9:

     ```
     sudo dnf install java-21-openjdk java-21-openjdk-devel -y
     ```
   * For RHEL 7:

     ```
     sudo yum install java-21-openjdk-devel -y
     ```
3. Verify Installation
   * Run the following command to verify the installation:

     ```
     java -version
     ```
   * Expected output:

     ```
     openjdk version "21.x.x"
     ```

     \
     Sample Reference Screenshot:

     <figure><img src="https://content.gitbook.com/content/gnJyYKHzsnoFOdZJtHsc/blobs/JvT75EQkTGuWgevLPZh7/unknown.png" alt=""><figcaption></figcaption></figure>

***

Copyright © 2026, OvalEdge LLC, Peachtree Corners, GA, USA.


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