Thanks guys. I want my visitors to read my contents. Thats why I'm more intersted to set up this. While going through facebook I found the below information. Can you please let me know is this is possible in our forum?
2. Facebook Crawler access
The Facebook Crawler fetches content from your site and generates a preview for people on Facebook. When someone shares a URL on Facebook and Likes or Recommends a page on your site using a plugin, it activates the Facebook Crawler. If your content is publicly available, we should have no problem accessing it.
If your content requires someone to login or if you restrict access after some amount of free content has been consumed, you will need to enable access for the Facebook Crawler. This access is only used to generate previews, and Facebook will not publicly expose your private content.
There are two methods to give Facebook’s Crawler access to your content:
IP whitelisting, which is more secure, but requires upkeep
User agent whitelisting, which is less secure, but requires little to no upkeep)
Your engineers can allow the following IP addresses access to pages that would otherwise be inaccessible to the public.
Please note that these IP ranges can and do change regularly, so you should periodically run the following command to receive an updated list
whois -h whois.radb.net -- '-i origin AS32934' | grep ^route
User agent whitelisting
Your engineers can allow the following user-agent access to pages that would otherwise be inaccessible to the public. We rarely update these user-agents, and users can spoof them. But since only a very small percentage of users know how to change their browser’s user-agent, the expected number of users who would exploit this is very low. Additionally, you also do not need to include all the URL's regular content to our crawler, just a valid HTML document with the appropriate meta tags.
Facebook’s crawler crawls with facebookexternalhit/<version_number>, where <version_number> is either 1.0 or 1.1, as of March 2013.
As of May 28th, 2014 you may also see a crawler with the following user agent string:
The Facebot crawler may crawl your entire website instead of just a single page. Facebot will respect your robots.txt settings.
Crawler rate limiting
You can label pages and objects to change how long Facebook's crawler will wait to check them for new content. Use the og:ttl object property to limit crawler access if our crawler is being too aggressive.