My website gains approximately 3000 visits per day and increasing steadily due to natural process, no spamming or black hat technique. But since it's on a shared host, I upgraded it to VPS for more performance. Unfortunately, the processing was too long and the website was down for 3 days. Now the website doesn't show up on Google search result with usual keywords, even the domain name (ie. romajidesu), as a result the traffic drop to 1/3 of normal. Has anyone experienced similar problem? How long will it take to regain the normal traffic? And what should I do now? Thank you very much!
This happened to me before when my host's server had a problem due to a defacement attack and was down for 1 week. But after I added my site's Sitemap to Google Webmaster Tools (GWT), the indexing of pages recovered after a few days. So just make sure that you add your site to GWT.