SergeyZ
Actually they use different servers/proxies/ip's to make the checks of vulnerable servers and sites. Also they use robots. This is why they check your site every 3-5 mins.
 
 
Below is the legacy version of the Boonex site, maintained for Dolphin.Pro 7.x support.
The new Dolphin solution is powered by UNA Community Management System.
PET:0.034720182418823