Website security is a continuous process. It’s not something that should be turned on when the time is right; rather integrated into the full scope of how you deploy a website, maintain it, and ensure the safety of your visitors.
At Sucuri, we protect websites with a wide range of website configurations, including business owners with a single website, multi-site WordPress installations, and web agencies who work with a number of clients. One of the biggest concerns for all of them – and an often overlooked aspect of security – is availability or downtime.
from Website Availability and Security When Migrating Hosts