Microsoft has jumped on the bandwagon for allowing you to verify if the useragent, MSNBot, that is crawling your site, is truly from Microsoft or being spoofed by some content scraper. Google has released information in the past for verifying Googlebot and it is excellent to see Microsoft doing the same.
To catch fake MSNBots you can do as follows:
- When you get a page view request, it specifies a user-agent and an IP address. As I described above, all requests from Live Search use a user agent starting with the word ‘MSNBot’.
- If you see the MSNBot user-agent, it’s time to check the identity of the bot. Starting with the IP address (i.e. 220.127.116.11), you can use reverse DNS lookup to find out the registered name of the machine.
- Once you have the host name (in this case, livebot-207-46-98-149.search.live.com), you can check that it really is coming from Live Search. The name of all live search crawlers will end with ‘search.live.com’. If the name doesn’t end with ‘search.live.com’, you know it’s not really our crawler.
- Finally, you need to verify that the name is accurate. In order to do this, you can use Forward DNS to see the IP address associated with the host name. This should match the IP address you used in Step 2 – if it doesn’t, it means the name was fake.
More details at the Live Search Blog.
Forum discussion at WebmasterWorld.