some minutes ago one of my collegues reported to me that he was unable to visit certain websites (like www.consist.de). Chrome returned that the connection was refused. However the website was in none of the categories that we block… (we block nudity, porn, weapons and hacking websites).
Furthermore the connection was slow… like something in the dome firewall was working slow. After I turned off the url filter the internet speed was back to normal and the refused websites started working again.
Hope you can investigate this.