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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The problem is you have both of those IP addresses in the same subnet with 192.168.50.0/24 so 192.168.50.1 is not in your EXTERNAL_NET.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Are you trying to trigger on outbound traffic?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Is HOST A on one interface and HOST B on another interface? Where is HOST B trying to send traffic to?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> oisf-users-bounces@openinfosecfoundation.org [mailto:oisf-users-bounces@openinfosecfoundation.org] <b>On Behalf Of </b>mouna amani<br><b>Sent:</b> Friday, June 14, 2013 1:07 PM<br><b>To:</b> oisf-users@openinfosecfoundation.org<br><b>Subject:</b> [Oisf-users] (no subject)<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>here is the deal I am a beginner with ips and everything<o:p></o:p></p><div><p class=MsoNormal>I have a host A with ip 192.168.50.3<o:p></o:p></p></div><div><p class=MsoNormal>an Host B with ip 192.168.50.1<o:p></o:p></p></div><div><p class=MsoNormal>the HostB sometimes sends good traffic and sometimes attacks .<o:p></o:p></p></div><div><p class=MsoNormal>I set HOME_NET:<a href="http://192.168.50.0/24">192.168.50.0/24</a><o:p></o:p></p></div><div><p class=MsoNormal>and EXTERNAL_NET: "!$HOME_NET"<o:p></o:p></p></div><div><p class=MsoNormal>if my hostB decides to send bad traffic the ips will generate an alert??<o:p></o:p></p></div><div><p class=MsoNormal> (I did not change the rules to drop)<o:p></o:p></p></div><div><p class=MsoNormal>or should I set EXTERNAL_NET to any<br clear=all><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div></body></html>