Ethical Hacking Learn to find vulnerabilities before the bad guys do! Gain real world hands on hacking experience in our state of the art hacking lab. Course designed and taught by expert instructors with years of penetration testing experience. 12 student maximum in every class. Certification attempt included in every package. | Computer Forensics Training at InfoSec Institute Gain the in-demand skills of a certified computer examiner, learn to recover trace data left behind by fraud, theft, and cybercrime perpetrators. Discover the source of computer crime and abuse at your organization so that it never happens again. All of our class sizes are guaranteed to be 12 students or less to facilitate one-on-one interaction with one of our expert instructors. |

| Subject: | Re: [Snort-users] Alerts of the ICMP relationship with smtp connection? |
|---|---|
| Date: | Tue, 31 May 2005 02:22:20 -0500 |
On Mon, 2005-05-30 at 13:40 -0700, Paulo wrote:
I didn't solve this yet. Please, anyone can help me?
Maybe you didn't get responses because it's not a Snort related issue. To answer your question, read up on Path Maximum Transmit Unit (PMTU) Discovery by googling it. Here a couple links that Google spit out right away. http://www.netheaven.com/pmtu.html which also references ftp://ftp.rfc-editor.org/in-notes/rfc1191.txt While you are learning about PTMU, please review your firewall rule set and make sure you don't block ALL inbound ICMP packets. Please let at least type 3 and type 11 ICMP packets through. (Hint: The remote mail servers are sending a large ICMP packet in order to discover the MTU between them and you. It is harmless traffic.) Hope that helps, Frank
signature.asc
Description: This is a digitally signed message part
| <Prev in Thread] | Current Thread | [Next in Thread> |
|---|---|---|
| ||
| Previous by Date: | Re: [Snort-users] Alerts of the ICMP relationship with smtp connection?, Paulo |
|---|---|
| Next by Date: | [Snort-users] Query, Mukesh |
| Previous by Thread: | Re: [Snort-users] Alerts of the ICMP relationship with smtp connection?, Paulo |
| Next by Thread: | [Snort-users] writing virus signatures, Siddhartha Jain |
| Indexes: | [Date] [Thread] [Top] [All Lists] |