My Linode CPU suddenly won't run at all

Your Linode's CPU usage is likely reflecting as 0% because an application is not running as opposed to your CPU not being allowed to run. I would encourage you to review the following guide to make sure that all necessary applications are running for your web server to resume functioning:

• Troubleshooting Web Servers, Databases, and Other Services | Linode Docs

If you are encountering any difficulties with a program that has not started automatically on-boot or has unexpectedly stop, you can attempt to start/restart or troubleshoot using the following commands:

• Check the status of the Application/Service:

sudo systemctl status $APPLICATION

• Start or Restart your Application/Service:

sudo systemctl start $APPLICATION

---

sudo systemctl restart $APPLICATION

• Stop your Application/Service:

sudo systemctl stop $APPLICATION

• Enable your Application/Service to automatically start after a reboot:

sudo systemctl enable $APPLICATION

• Check the system error logs for the specific Application/Service:

journalctl -xe

It may also be beneficial to review this guide on what to do if your Linode becomes unreachable following major changes or system maintenance:

• My Linode is unreachable after maintenance (323) | Linode Questions

Although our Support Team won't be able to take server-internal or administrative action for you, it can also be helpful to open a ticket in Cloud Manager so that we can rule out issues with our infrastructure and provide topical guidance.