Re: [gentoo-server] how to stop tracing

[Andrew Gaffney <agaffney@gentoo.org>]

Christopher Dale wrote:
> widyachacra wrote:
>> Dear List friends,
>>
>> When i scan my own domain from an out side host using 'nmap' tool it shows
>> following results. How do i block this kind of tracing using linux. Please
>> help me.
>>
>> nmap tracing result,
>>
>> PORT    STATE SERVICE    VERSION
>> 25/tcp  open  smtp       netqmail smtpd 1.04
>> 53/tcp  open  domain
>> 80/tcp  open  http       Apache httpd 2.2.6 ((Gentoo))
>> 110/tcp open  pop3       Courier pop3d
>> 119/tcp open  ssh        OpenSSH 4.7 (protocol 2.0)
>> 209/tcp open  tam?
>> 443/tcp open  http       Apache httpd 2.2.6 ((Gentoo))
>> 628/tcp open  tcpwrapped
>> 993/tcp open  ssl/imap   Courier Imapd (released 2005)
>> 995/tcp open  ssl/pop3   Courier pop3d
>>
>>
>>   
> Hi Widyachacra,
> 
> Great question and one that I have had in the past also. In a previous
> post to the gentoo mailing list, someone suggested that port knocking be
> used as a means of securing through obscurity. After looking at it
> (http://www.portknocking.org), I've found that it's a wonderful means to
> a personal server's security when exposed to the world wide web.
> 
> All the best in your attempts to obfuscate your server's open ports! :)

Unfortunately, this *only* works when it's a private server. This is not an 
acceptable solution on a server accessed by the "public".

-- 
Andrew Gaffney                                 http://dev.gentoo.org/~agaffney/
Gentoo Linux Developer             Catalyst/Installer + x86 release coordinator
-- 
gentoo-server@lists.gentoo.org mailing list