Hi, all
On our servers, the following UAs are blocked and similar repeated requests against large iso files can be rejected:
map $http_user_agent $isbadbrowser {
default 0;
"~*Mozilla/5\.0 \(Linux; Android\)" 1;
"~*Chrome/49\.0\.2623\.87" 1;
"~*Firefox/3.6.3" 1;
}
According to our experience of operating largest mirror site in China, such User-Agent list is able to protect against most of those traffic, IP blocking is not needed and the list didn't require an update for several years.
Although the root cause not found, we suspect these behavior might be caused by some certain broken software and the problem might already be solved in a later version. It will be appreciated if anyone can report traffic with this pattern from AS4538, and we can try to figure out what is the root cause of such behavior.
Cheers,
Miao Wang
> 2020年10月06日 21:47，Didier Aeschimann <didier at calgah.com> 写道：
>
> Hello,
>
> We also had a similar issue in 2019
>
> May 2019 6768.16 GB
> Jun 2019 4571.42 GB
> Jul 2019 5033308.72 GB
> Aug 2019 1665015.47 GB
> Sep 2019 480864.23 GB
> Oct 2019 7492.56 GB
>
> All of the increase in traffic was China networks.
> In my case we waited it out and still have about 50% over normal from China.
> We were wondering what CentOS’ position on geoblocking is?
>
> Good day,
>
> Didier
>
> Didier Aeschimann
> Calgah Computer Systems Ltd. / IT Security Division
> 1405 Henri-Bourassa E.
> Montreal, Quebec, Canada H2C 1H1
> Tel:(514) 335 0405 Fax. (514) 335 6541
> Email: nospam at redwarning.com, didier at calgah.com
> http://www.calgah.com
>
>
>
> From: CentOS-mirror <centos-mirror-bounces at centos.org> On Behalf Of Cihan Nimsi via CentOS-mirror
> Sent: October-06-20 09:23
> To: centos-mirror at centos.org
> Subject: Re: [CentOS-mirror] [Ticket#2020100504000801] Potential DOS attack against a mirror
>
> Hello,
>
> We also had the same problem and blocked China. Problem solved.
>
> 6.10.2020 01:23 tarihinde Christopher Hawker yazdı:
>> Hi Thomas,
>>
>> You could simply use GeoIP Blocking to filter out any traffic from China. Here's a link to achieve this for Apache: https://www.cloudibee.com/geoip-based-country-blocking-for-apache/.
>>
>> Regards,
>> Christopher Hawker
>>
>>
>> From: CentOS-mirror <centos-mirror-bounces at centos.org> on behalf of Thomas Enos <thomas.enos at afghan-wireless.com>
>> Sent: Tuesday, 6 October 2020 4:34 AM
>> To: Mailing list for CentOS mirrors. <centos-mirror at centos.org>; CEDIA FOSS Mirrors <mirror at cedia.org.ec>
>> Subject: Re: [CentOS-mirror] [Ticket#2020100504000801] Potential DOS attack against a mirror
>>
>> We can confirm being hit by 27.221.66.0/24 pulling the same iso as well. What action was taken to address this by your networks?
>>
>> Thanks,
>>
>> From: CentOS-mirror <centos-mirror-bounces at centos.org> on behalf of Bogdan-Stefan Rotariu <bogdan.rotariu at chroot.ro>
>> Reply to: "Mailing list for CentOS mirrors." <centos-mirror at centos.org>
>> Date: Monday, 5 October 2020 at 9:30 PM
>> To: CEDIA FOSS Mirrors <mirror at cedia.org.ec>, "Mailing list for CentOS mirrors." <centos-mirror at centos.org>
>> Subject: Re: [CentOS-mirror] [Ticket#2020100504000801] Potential DOS attack against a mirror
>>
>> [EXTERNAL EMAIL] This is an external email, please make sure the sender is well known before clicking on any link or opening an attachment, if spam report it to CIRT at afghan-wireless.com
>>
>> Hi there,
>>
>> On Oct 5, 2020, at 20:24, CEDIA FOSS Mirrors via CentOS-mirror <centos-mirror at centos.org> wrote:
>> hi
>>
>> <snip>
>>
>> 112.95.214.226 - China Unicom Guangdong province network
>> 223.88.61.170 - China Mobile Communications Corporation
>> 171.41.7.29 - CHINANET Hubei province network
>> 120.84.10.190 - China Unicom Guangdong province network
>> 27.221.66.104 - China Unicom Shandong province network
>> 27.221.66.105 - China Unicom Shandong province network
>> 112.32.21.93 - China Mobile Communications Corporation
>> 27.221.49.135 - China Unicom Shandong province network
>>
>> Have you noticed that in your mirrors? look for these IP and notice if they have been trying to continously download iso
>>
>> We did encounter the same issues with the same IP addresses and same iso file. Till now I thought it was an isolated issue..
>>
>> —
>> Bogdan-Stefan Rotariu
>> CTO,Founder
>> Chroot Network SRL
>> WEB: http://www.chroot.ro<http://track.chroot.ro/?a=10395&m=&n=&s=12c000000d625fc&u=http%3a%2f%2fwww.chroot.ro%3futm_source%3d%26utm_medium%3demail%26utm_campaign%3dunspecified&t=&e=contact%40chroot.ro&h=8a6c74da>
>> Phone: +40-731-247-668<tel:+40-731-247-668>
>> Suport tehnic: suport at chroot.ro<mailto:suport at chroot.ro>
>> Suport vanzari: vanzari at chroot.ro<mailto:vanzari at chroot.ro>
>> Contact general: contact at chroot.ro<mailto:contact at chroot.ro>
>>
>> _______________________________________________
>> CentOS-mirror mailing list
>> CentOS-mirror at centos.org
>> https://lists.centos.org/mailman/listinfo/centos-mirror
>>
>>
>> _______________________________________________
>> CentOS-mirror mailing list
>> CentOS-mirror at centos.org
>> https://lists.centos.org/mailman/listinfo/centos-mirror
> --
> İyi Çalışmalar / Best Regards,
> Cihan Nimsi
> C-Level Executive
>
>
> İçerenköy Mh. Ertaç Sk. Ardil İş Merkezi
> No: 4/2 Kat: 1 Ataşehir/İSTANBUL
> Telefon +90 850 885 0 558 - 1001
> www.guzel.net.tr
>
> Bu e-mailin içeriği gizlidir ve sadece bu e-mailin alıcısına özeldir. Göndericinin izni olmadan bu mesajın 3. taraflarla paylaşılması yasaktır. Eğer bu e-mail size yanlışlıkla gönderildiyse, lütfen bu e-maili yanıtlayıp siliniz, böylece aynı hata tekrar olmayacaktır.
> The content of this email is confidential and intended for the recipient specified in message only. It is strictly forbidden to share any part of this message with any third party, without a written consent of the sender. If you received this message by mistake, please reply to this message and follow with its deletion, so that we can ensure such a mistake does not occur in the future.
>
> _______________________________________________
> CentOS-mirror mailing list
> CentOS-mirror at centos.org
> https://lists.centos.org/mailman/listinfo/centos-mirror