A Webmaster Trends Analyst for Google, John Mueller, wrote up a blog post that explains how SEOs and webmasters can handle site outages or closures that last for a day or longer.  Basically, this is when a webmaster will take down the site intentionally for maintenance, site moves, religious reason, or any other reason for that matter.

John offers three options:

  1. Block the cart functionality from Google and your users.
  2. Always show an interstitial or pop-up saying your site is offline today.
  3. Switch the whole website off for a period of time.

Every option here can be handled in a different way, but it blocking the cart functionality is the easiest option if you don’t want people buying from your site.

There will be some webmasters who want to take the whole site offline and offer a warning, such as an interstitial or pop-up with an explanation of why the site isn’t accessible.  Google has told those who are worried about this that interstitials for religious purposes are within their acceptable use guidelines. These sites won’t or shouldn’t, in this case, be hit by the Google interstitials penalty.

When doing this, John Mueller said “the server should return a 503 HTTP result code (“Service Unavailable”) … The 503 result code makes sure that Google doesn’t index the temporary content that’s shown to users. Without the 503 result code, the interstitial would be indexed as your website’s content.”

Same with turning off the site, but also add these tips to your to-do list:

  1. Set your DNS TTL to a low time (such as five minutes) a few days in advance.
  2. Change the DNS to the temporary server’s IP address.
  3. Take your main server offline once all requests go to the temporary server.
  4. … your server is now offline …
  5. When ready, bring your main server online again.
  6. Switch DNS back to the main server’s IP address.
  7. Change the DNS TTL back to normal.

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