How to Uninstall OpenStack on Ubuntu

OpenStack is a popular open-source cloud computing platform that provides infrastructure as a service (IaaS). While it offers a robust set of tools for deploying and managing virtualized resources, there may come a time when you need to uninstall it, perhaps to free up resources, troubleshoot, or transition to a different platform.

This guide will walk you through the process of uninstalling OpenStack on an Ubuntu system. Before proceeding, it’s essential to understand the implications of this action. Uninstalling OpenStack will remove all associated data, configurations, and virtual instances.

Let’s get started.

Step 1: Backup Your Data

Before making any significant changes to your system, it’s always a good practice to backup essential data. This includes any configurations, databases, or virtual instances you may have within OpenStack.

Navigate to the /etc/openstack directory and create a backup of all configuration files.

sudo tar -czvf openstack-config-backup.tar.gz /etc/openstack/

Backup any databases used by OpenStack. If you’re using MySQL or MariaDB, you can use the mysqldump command.

Step 2: Stop OpenStack Services

Before uninstalling, ensure all OpenStack services are stopped.

sudo service openstack stop

Step 3: Remove OpenStack Packages

OpenStack consists of multiple components, each with its own set of packages. Use the package manager to remove them.

sudo apt-get purge nova* cinder* glance* neutron* keystone* horizon* openstack*

Step 4: Remove Dependencies

After uninstalling OpenStack packages, you might have unused dependencies left on your system. Clean them up using:

sudo apt-get autoremove

Step 5: Remove Configuration Files and Directories

Even after uninstalling the packages, configuration files and directories might remain. Ensure you remove them to free up space and avoid potential conflicts in the future.

sudo rm -r /etc/nova /etc/cinder /etc/glance /etc/neutron /etc/keystone /etc/horizon /etc/openstack

Step 6: Clean Up Databases

If you’ve used databases like MySQL or MariaDB with OpenStack, it’s a good idea to clean them up to ensure no remnants of OpenStack remain.

sudo mysql -u root -p -e "DROP DATABASE nova;"
sudo mysql -u root -p -e "DROP DATABASE cinder;"
sudo mysql -u root -p -e "DROP DATABASE glance;"
sudo mysql -u root -p -e "DROP DATABASE neutron;"
sudo mysql -u root -p -e "DROP DATABASE keystone;"

Step 7: Remove Users and User Groups

OpenStack creates specific users and groups for its services. To ensure a complete cleanup, remove these users and groups.

sudo userdel -r nova
sudo userdel -r cinder
sudo userdel -r glance
sudo userdel -r neutron
sudo userdel -r keystone
sudo groupdel nova
sudo groupdel cinder
sudo groupdel glance
sudo groupdel neutron
sudo groupdel keystone

Step 8: Clean Up Networking

If you’ve set up networking configurations specific to OpenStack, such as bridges or virtual interfaces, ensure you remove or reconfigure them as needed.

Step 9: Reclaim Disk Space

OpenStack can use significant disk space, especially if you’ve had many instances or images. After uninstalling, it’s a good idea to reclaim this space.

sudo rm -rf /var/lib/nova
sudo rm -rf /var/lib/cinder
sudo rm -rf /var/lib/glance
sudo rm -rf /var/lib/neutron

Step 10: Final System Update

After all the cleanup, it’s a good practice to update your system to ensure all packages are up-to-date.

sudo apt-get update && sudo apt-get upgrade

Commands Mentioned

• sudo tar -czvf openstack-config-backup.tar.gz /etc/openstack/ – Backs up OpenStack configurations.
• sudo service openstack stop – Stops all OpenStack services.
• sudo apt-get purge nova* cinder* glance* neutron* keystone* horizon* openstack* – Removes all OpenStack packages.
• sudo apt-get autoremove – Removes unused dependencies.
• sudo rm -r /etc/nova /etc/cinder /etc/glance /etc/neutron /etc/keystone /etc/horizon /etc/openstack – Deletes OpenStack configuration files and directories.
• sudo mysql -u root -p -e “DROP DATABASE …;” – Drops OpenStack-related databases.
• sudo userdel -r … – Removes OpenStack-related users.
• sudo groupdel … – Removes OpenStack-related user groups.
• sudo rm -rf /var/lib/nova … – Deletes OpenStack data directories.
• sudo apt-get update && sudo apt-get upgrade – Updates and upgrades system packages.

FAQ

1. Why would I need to uninstall OpenStack?

   There are several reasons to uninstall OpenStack, including freeing up system resources, troubleshooting issues, transitioning to a different platform, or performing a clean reinstallation.

2. Is it safe to uninstall OpenStack?

   Yes, but it’s crucial to backup any essential data and configurations before proceeding. Uninstalling OpenStack will remove all associated data, configurations, and virtual instances.

3. What happens to the virtual instances after uninstalling?

   Once OpenStack is uninstalled, all virtual instances managed by it will be deleted, and their data will be lost unless backed up separately.

4. Can I reinstall OpenStack after uninstalling?

   Yes, you can reinstall OpenStack after uninstalling. Ensure you have all necessary configurations and data backed up if you wish to restore your previous setup.

5. Are there alternatives to OpenStack?

   Yes, there are several alternatives to OpenStack for cloud computing, such as VMware vCloud, Microsoft Azure Stack, and Apache CloudStack. Additionally, for hosting solutions, consider dedicated servers, VPS, cloud hosting, or shared hosting.

Conclusion

Uninstalling OpenStack from Ubuntu is a multi-step process that requires careful attention to detail. By following this guide, you ensure that all components of OpenStack are thoroughly removed from your system.

Always remember to backup essential data and configurations before making significant changes.

If you’re looking for other cloud or hosting solutions, there are various options available, each with its own set of advantages. Whether you’re considering a dedicated server, VPS, cloud hosting, or shared hosting, ensure you choose a solution that aligns with your needs and goals.