I’ll let you in to a secret. I sometimes look at the analytics on this site. I anonymize the last octet of the address of course, using the piwik plugin. One of the things I look at is the referrers that are sending me traffic. In December and January I was seeing an improbably amount of traffic from semalt.com. And I realized that they were trying a marketing technique I had not seen before.
Semalt describe themselves as a professional webmaster analytics tool that opens the door to new opportunities for the market monitoring, yours and your competitors’ positions tracking and comprehensible analytics business information
. Which is a longwinded way of saying fuck all. I think that they are basically a competitor analysis tool.
The interesting thing is their new approach to marketing. It is pretty cheap to write a bot that visits a page on each bllog in the world, and one assumes that a reasonable percentage of those visited will be vain or curious enough to head over to semalt’s site. If even a small amount of them convert, that is still a reasonable investment.
Personally, I have no interest in their product. I have not received any visits from them in February, but for a while in January I had a few lines in my varnish config to discourage them from wasting my (and their) bandwidth. Here was what I did in /etc/varnish/default.vclsub vcl_recv {
if (req.http.referer && req.http.referer ~ "^http://semalt.com") {
error 403 "Why u waste my bandwidth, semalt?";
}
}
If you want an Apache rule to achieve the same thing you can follow Kenneth Yau’s advice and add this to your .htaccess or vhost config# block visitors referred from semalt.com
RewriteEngine on
RewriteCond %{HTTP_REFERER} semalt\.com [NC]
RewriteRule .* - [F]