Snort mailing list archives
Re: Bad Loop Back Traffic
From: "Scott Elgram" <SElgram () verifpoint com>
Date: Wed, 25 Feb 2004 15:03:47 -0800
Actually my set-up goes like this; Internet connects to router, connects to hub, hub connects to firewall. Also connected to the hub is eth0 on the SNORT machine with no IP. A second card (eth1) on the SNORT machine connects to the internal network so that I can monitor with ACID. This setup works good, the SNORT sensor sees all traffic coming in from the router and going out to the router. So far the only problem it seems to have is the Bad Loop Back Traffic -Scott Elgram ----- Original Message ----- From: "SN ORT" <snort_on_acid () yahoo com> To: <SElgram () verifpoint com> Cc: <snort-users () lists sourceforge net> Sent: Wednesday, February 25, 2004 2:01 PM Subject: Re: [Snort-users] Bad Loop Back Traffic
So you have this hub, connected to both the firewall and the router. Do you also have another connection, connecting the router to the firewall? Now the firewall and the router have two connections to each other? If you have a switch in between as well, this would cause a spanning tree problem. Or is this hub the only connection between the two? If not, then I would suggest a different way to monitor the connections, such as a switch between the router/fw and if you have that already, the switch should then mirror the router port only. If the hub is the only connection then is your sensor acting as a router? And your IP of you non-sniffing Interface is an internal IP connected internally? Cheese! MarcMessage: 5 Reply-To: "Scott Elgram" <SElgram () verifpoint com> From: "Scott Elgram" <SElgram () verifpoint com> To: <snort-users () lists sourceforge net> Subject: Re: [Snort-users] Bad Loop Back Traffic Date: Tue, 24 Feb 2004 09:52:35 -0800 Organization: VerifPoint/CreDENTALsHummm, interesting, I have my SNORT installed on RH9 with 2 interfaces. The interface with the sensor is connected to a hub between my router and firewall. The interface has no IP address and catches onlyout->bound and in-bound trafficfrom the internet. For a while I was under the impression that this "Bad Loop Back Traffic" was the result of having an interface up with no IP or configuration. Could this be the reason you think? -Scott Elgram----- Original Message ----- From: <bclark () bwkip com> To: <snort-users () lists sourceforge net> Cc: <SElgram () verifpoint com> Sent: Tuesday, February 24, 2004 9:01 AM Subject: Re: [Snort-users] Bad Loop Back TrafficI have also seen this type of traffic about 200,000alerts last night. Iam not sure but I think it is a clients Windowsmachine.Hello, I have an abundance of alerts telling me url[snort] BAD-TRAFFIC loopback traffic on127.0.0.1:80According to snort this is due to improperlyconfigured interfaces. =Which part is improperly configured and how can Ifix this? Or have I =been hacked? -Scott Elgram IT/Systems Support VerifPoint/CreDENTALs (949)770-5290 ext. 26__________________________________ Do you Yahoo!? Yahoo! Mail SpamGuard - Read only the mail you want. http://antispam.yahoo.com/tools
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Current thread:
- Bad Loop Back Traffic Scott Elgram (Feb 24)
- <Possible follow-ups>
- Re: Bad Loop Back Traffic bclark (Feb 24)
- Re: Bad Loop Back Traffic Mat Harris (Feb 24)
- Re: Bad Loop Back Traffic Frank Knobbe (Feb 24)
- Re: Bad Loop Back Traffic Scott Elgram (Feb 25)
- RE: Bad Loop Back Traffic Finney Charles E (Feb 24)
- Re: RE: Bad Loop Back Traffic Scott Elgram (Feb 25)
- Re: RE: Bad Loop Back Traffic James Nonya (Feb 24)
- Re: Bad Loop Back Traffic SN ORT (Feb 25)
- Re: Bad Loop Back Traffic Scott Elgram (Feb 27)
- Re: Bad Loop Back Traffic Mark . Schutzmann (Feb 27)