>>>>> "DD" == David Dorgan <dorgand at eircom.net> writes:
>> This is where you find, read and implement the Firewalling HOWTO.
DD> The issue here is not Firewalling....it is detecting scans.
DD> As regards Firewalling...if I have a router and put a deny all
DD> and leave port 80 open, a host program will not inform you of
DD> a portscan...therefor Firewalling is useless in this case at
Which you can do with iptables/ipchains *without* having unnecessary
open ports that the whole world can see.
>> Of course, you still have to ensure that the applications
>> running on the still-open ports are up to date.
DD> Once again off the point.
Not if some random script kiddie is running exploits against your open
ports, such as maybe your httpd or your sshd
>> I believe there is a way to get Portsentry to use ipchains to
>> block IPs that are port-scanning you, which may be helpful.
DD> The point being made is that showing open ports and setting
DD> off alarm bells and exploits flying at you is the wrong
DD> thing...transparent yet clearly viewable logging of such
DD> events is what is needed.
Well, duh. That's why I brought up firewallling in the first place:
you can drop and log packets without ever giving any indication that
they were received. You get the best of both worlds: no spurious open
ports, and you can see when you're being scanned.
"Pity has no place at my table."
-- Dr Hannibal Lecter
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