What precautionary steps should I take before resizing a linode disk?

My linode server has unallocated storage that I'd like to use to upgrade the size of the main disk running the Ubuntu installation. There is a single WooCommerce site on the disk (and a smaller staging site), but the site is huge and growing at a rapid pace. I don't want to risk losing the site/installation when I resize the disk, so I was wondering, what's the most effective way to prepare for the worst?

Solution

All you really need to do is make sure you do a clean shutdown. Then you'll be fine. As a precaution you should backup as well.

On Linode you can do this a few different ways. Choose one or more depending on how paranoid you want to be:

freeze the image with Linode Images, then you can "thaw" it out later if you need it (https://www.linode.com/docs/platform/disk-images/linode-images/)
download the image via dd and SSH so that you have a local backup (https://www.linode.com/docs/platform/disk-images/copying-a-disk-image-over-ssh/)
duplicate the image before you resize it (you need enough room on your Linode plan for this)