In a webmaster hangout on YouTube, Google’s John Mueller said that your log files can show you if your website has been moved to the mobile-first index.
According to John Mueller, 80% of Googlebot crawling is done by their desktop crawler, and 20% are done by the mobile crawler. If your website is in the mobile-first index, you will see an 80% crawl rate by the mobile version of Googlebot in your log files and a 20% crawl rate by the desktop version:
“You would probably recognize it in the log files. If you see, if you look now, probably something like 80% of the crawling is with the Googlebot desktop and maybe 20% is with mobile with the smartphone Googlebot.
That will shift over and most of the crawling will be done with the smartphone Googlebot and less crawling with the desktop Googlebot. So if you really watch out for your log files probably you can notice that fairly obviously.”
You can view the video here:
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