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<div style="font-family: Calibri, sans-serif;">Additionally, if you are not running it in NFQ mode, you could also leverage the pass feature assuming that you can easily identify traffic that you don’t want to inspect: <a href="http://suricata.readthedocs.io/en/suricata-4.0.4/performance/ignoring-traffic.html?highlight=pass">http://suricata.readthedocs.io/en/suricata-4.0.4/performance/ignoring-traffic.html?highlight=pass</a></div>
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<div style="font-family: Calibri, sans-serif;">Best Regards, </div>
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<p class="MsoNormal" style="font-family: Calibri, sans-serif;"><b><span style="font-family:Arial;color:#1D0E00">Brad Woodberg
</span></b><span style="font-family:Arial;color:#1D0E00">l<b> </b>Group Product Manager, ETPro, Security Tools</span><span style="font-size:16.0pt"><o:p></o:p></span></p>
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<span style="font-weight:bold">From: </span>Oisf-users <<a href="mailto:oisf-users-bounces@lists.openinfosecfoundation.org">oisf-users-bounces@lists.openinfosecfoundation.org</a>> on behalf of Amar Rathore - CounterSnipe Systems <<a href="mailto:amar@countersnipe.com">amar@countersnipe.com</a>><br>
<span style="font-weight:bold">Date: </span>Monday, April 23, 2018 at 6:30 AM<br>
<span style="font-weight:bold">To: </span>Kevin Branch <<a href="mailto:kevin@branchnetconsulting.com">kevin@branchnetconsulting.com</a>>, "<a href="mailto:oisf-users@lists.openinfosecfoundation.org">oisf-users@lists.openinfosecfoundation.org</a>" <<a href="mailto:oisf-users@lists.openinfosecfoundation.org">oisf-users@lists.openinfosecfoundation.org</a>><br>
<span style="font-weight:bold">Subject: </span>Re: [Oisf-users] How to prevent Suricata from inspecting traffic already locally blocked by iptables<br>
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<p style="font-size: 12pt; font-family: arial, helvetica, sans-serif; color: rgb(0, 0, 128);">
Hello Kevin</p>
<p style="font-size: 12pt; font-family: arial, helvetica, sans-serif; color: rgb(0, 0, 128);">
Assuming you are running Suricata in NFQ mode, you should be able to direct (by iptables rule) just the http/https traffic to Suri. You control this further by destination/port based rule too. In which case you won't be seeing any other alerts! </p>
<p style="font-size: 12pt; font-family: arial, helvetica, sans-serif; color: rgb(0, 0, 128);">
You should also be able to fine tune the IDS rule set to a point that it only monitors the traffic you require.</p>
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We have a number of in cloud servers running exactly the same way and will be happy to share configs if required.</p>
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Amar</p>
<blockquote type="cite">On April 22, 2018 at 10:26 PM Kevin Branch <<a href="mailto:kevin@branchnetconsulting.com">kevin@branchnetconsulting.com</a>> wrote:
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Hi all,</div>
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<span style="color: #222222; font-family: arial,sans-serif; font-size: 12.8px; font-style: normal; font-weight: 400; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; background-color: #ffffff; float: none; display: inline;">I've
used Suricata for years but always on a dedicated NIDS server for inspecting traffic behind a network firewall. Now I am trying a local install of Suricata on a Linux cloud server whose traffic I want to inspect. The server uses iptables to block all incoming
connections other than http/https. My problem is that Suricata is generating lots of alerts about incoming connection attempts (scanning noise) that iptables is blocking anyway, which I would rather not hear about.</span>
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Is there a way to make Suricata ignore packets that have already been dropped by the local iptables? I've toyed with the idea of using the iptables tee facility to pump a subset of eth0 traffic to a dummy0 interface and then having Suricata inspect that instead,
but I thought I'd check in here to see if anyone has a better approach already working for them.</div>
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Thanks,</div>
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Kevin</div>
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