alert http $EXTERNAL_NET any -> $HTTP_SERVERS any (msg:"ET POLICY Pingdom.com Monitoring detected"; flow:to_server,established; http.user_agent; content:"Pingdom"; startswith; nocase; reference:url,royal.pingdom.com/?p=46; classtype:attempted-recon; sid:2003214; rev:6; metadata:created_at 2010_07_30, confidence High, signature_severity Informational, updated_at 2024_02_06;)