Tracking the DNS amplification attacks (was: isprime DOS in progress)

James Hess mysidia at gmail.com
Sun Jan 25 03:23:05 CST 2009


On Sat, Jan 24, 2009 at 9:00 PM, Frank Bulk <frnkblk at iname.com> wrote:
> I would not recommend sucking in your dns log into array, rather, read line
> by line and iterate over the file, line by line.
>
> Frank

True.. reading into an array can get a bit nasty, if your server logs
are a few gigabytes in size.

Could use C, also...

http://pastebin.com/f4c2ff010


Scanning your logs after the fact is definitely not as good as
separating DNS servers that
are authoritative for zones and picking nameserver software such as
TinyDNS or similar options
for authoritative DNS usage that won't respond  to queries for the
root  or other zones the DNS
server is not directed to be used for,

and using acls/firewalls to prevent outside queries against other DNS
servers that aren't
delegated zones.


It's a bit difficult to apply a BIND patch that doesn't exist  yet in
vendor-supplied implementations
of BIND, at least..

--
-J




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