[54450] in North American Network Operators' Group
Re: DDos syn attack
daemon@ATHENA.MIT.EDU (Sean Donelan)
Wed Jan 1 23:50:16 2003
Date: Wed, 1 Jan 2003 23:49:41 -0500 (EST)
From: Sean Donelan <sean@donelan.com>
To: Avleen Vig <lists-nanog@silverwraith.com>
Cc: "nanog@merit.edu" <nanog@merit.edu>
In-Reply-To: <20030101192642.T45157@guava.silverwraith.com>
Errors-To: owner-nanog-outgoing@merit.edu
On Wed, 1 Jan 2003, Avleen Vig wrote:
> Tracing back an IP from bind logs to see which name servers looked up an
> attacked address immediately before the attack started. This at leads to
> the offender's ISP which is a good start.
Relatively few people restrict the use of their name servers to only
local users. More folks have been getting DNS servers from DHCP/Radius,
but there are still a lot of users with hard-coded resolvers. There may
be a few DNS resolvers which keep track of query sources, but more than
likely you'll end up at another dead-end because the true source will be
somewhere else.
Let's add port 53 to the every growing list of ports to block.
