Another great article from Yoast.com
How bad hosting can lead to losing SEO rankings
Downtime of your website can lead to vastly decreased performance in organic search. I’ve been saying this for years, and have had some small examples to show for it. Now though, I’ve got a great example that I wanted to share with you. The client in this case was Independer.nl and they lost a very important ranking (for the word autoverzekering, Dutch for car insurance) for half a day due to unscheduled downtime. It’s a perfect example of why good hosting and monitoring are so important.
What happened was that at around midnight, the servers would start to run a backup. A very smart process to have in place, of course, but for the course of that backup, about 10-15 minutes, a small percentage of visitors would be redirected to a “temporarily not available” page. This page gave a 404 error, causing Google to remove the page from its index, because it thought the page no longer existed. Good thing Google checks pages that have given a 404 error again after a while, so they didn’t loose their rankings forever but just for the course of about half a day.
Several things are wrong here: first of all the page should have given a 503 status code, which means “temporarily unavailable”. If it had, Google would just have come back to it rather quickly and not have removed the page from its index. Second; the page shouldn’t have been redirecting or giving an error at all; your backup process should run without that much influence on your website. That’s the only proper way of not having your hosting affect your SEO.