In case of a critical system failure which prevents your server from functioning, or access to it, such as:
Bad kernel update
Broken file system
Lost password
Misconfigured network interface or firewall
And other issues
You can use the "Server Recovery" option in your dedicated server management page to load up System Rescue live image, which allows you to use a number of tools to help you fix various issues.
Once you have navigated to this section, enter a temporary root password (does not need to match your current server root password), and press "Submit".
After 5-10 minutes you will be able to log in-to the Rescue image loaded onto your Dedicated server via ssh.
Connect to your: ssh root@255.255.255.255 (replace the IP with the main IP of your dedicated server).
You might need to remove your current host fingerprint.
Use the password that you provided.
You can find the list of available tools here: https://www.system-rescue.org/System-tools/
You can also add any other tools you might need via pacman: https://www.system-rescue.org/manual/Installing_packages_with_pacman/
Additionally, in order to manage the data on your server, you will commonly use chroot: https://wiki.archlinux.org/title/chroot
Feel free to install any tools required to restore your server to working order.
Once you are done diagnosing/fixing your server, press "Cancel operation" under the "Server Recovery" tab and restart the server via the "Server Power control" tab.