I did a test on my personal server of filtering every IP network assigned to China for a few months and over 90% of SSH attempts and other noise just went away. It was pretty remarkable. Working for a public university I can't block China outright, but there are times it has been tempting. :-) The majority of DDOS attacks I see are sourced from addresses in the US, though (likely spoofed). Just saw a pretty large one last week which was SSDP 1900 to UDP port 80, 50K+ unique host addresses involved. On Wed, Mar 18, 2015 at 8:32 AM, Eric Rogers <ecrogers@precisionds.com> wrote:
We are using Mikrotik for a BGP blackhole server that collects BOGONs from CYMRU and we also have our servers (web, email, etc.) use fail2ban to add a bad IP to the Mikrotik. We then use BGP on all our core routers to null route those IPs.
The ban-time is for a few days, and totally dynamic, so it isn't a permanent ban. Seems to have cut down on the attempts considerably.
Eric Rogers PDSConnect www.pdsconnect.me (317) 831-3000 x200
-----Original Message----- From: NANOG [mailto:nanog-bounces@nanog.org] On Behalf Of Roland Dobbins Sent: Wednesday, March 18, 2015 6:04 AM To: nanog@nanog.org Subject: Re: Getting hit hard by CHINANET
On 18 Mar 2015, at 17:00, Roland Dobbins wrote:
This is not an optimal approach, and most providers are unlikely to engage in such behavior due to its potential negative impact (I'm assuming you mean via S/RTBH and/or flowspec).
Here's one counterexample:
<https://ripe68.ripe.net/presentations/176-RIPE68_JSnijders_DDoS_Damage_ Control.pdf>
----------------------------------- Roland Dobbins <rdobbins@arbor.net>
-- Ray Patrick Soucy Network Engineer University of Maine System T: 207-561-3526 F: 207-561-3531 MaineREN, Maine's Research and Education Network www.maineren.net