https://DevOpsCloud.io -- Cloud Monk Losang Jinpa, Ph.D., MCSE/MCT, GitOps DevOps Engineer

Return to yum

The command `yum update` is used to update all installed packages on a system that uses the Yellowdog Updater, Modified (YUM) package manager. YUM is commonly found on Linux distributions like CentOS, Fedora, and Red Hat Enterprise Linux.

**Here's what happens when you run `yum update`:**

1. **Checks for Updates:** YUM connects to configured repositories (online sources for packages) and checks if there are any newer versions available for the packages installed on your system.

2. **Lists Updates:** If updates are found, YUM displays a list of packages that will be updated and the version changes.

3. **Prompts for Confirmation:** YUM asks you to confirm if you want to proceed with the updates. You can type 'y' to continue or 'n' to cancel.

4. **Downloads and Installs Updates:** If you confirm, YUM downloads the necessary packages and installs them, replacing the older versions.

5. **Resolves Dependencies:** YUM automatically handles dependencies, ensuring that any required libraries or other packages are also updated or installed.

**Important Considerations:**

• **Root Privileges:** You need to run `yum update` with root privileges (using `sudo` or logging in as root) because it modifies system files.
• **Network Connection:** An active internet connection is required to download updates from the repositories.
• **System Reboot:** In some cases, a system reboot may be necessary after updating the kernel or other critical packages. YUM will inform you if a reboot is required.
• **Backup:** It's always a good practice to back up your important data before performing major system updates, although YUM is generally reliable.

**Alternative:**

If you only want to update a specific package instead of all packages, you can use `yum update package_name`.

**Remember:** Keeping your system up-to-date is crucial for security and stability. Regularly running `yum update` helps ensure that you have the latest bug fixes, security patches, and feature enhancements.

**References:**

• **YUM Command Cheat Sheet:** s://access.redhat.com/sites/default/files/attachments/rh_yum_cheatsheet_1214_jcs_print-1.pdf(https://access.redhat.com/sites/default/files/attachments/rh_yum_cheatsheet_1214_jcs_print-1.pdf)
• **Chapter 9. Yum ]] | //docs.redhat.com/en/documentation/red_hat_enterprise_linux/7/html/system_administrators_guide/ch-yum) * **Linux package management with YUM and RPM | [[ Enable Sysadmin - Red Hat:** s://www.redhat.com/sysadmin/how-manage-packages(https://www.redhat.com/sysadmin/how-manage-packages)