[CentOS-mirror] DDOS Attacks

Tue Aug 5 23:24:09 UTC 2014
Anssi Johansson <centos at miuku.net>

6.8.2014 1.59, Paul Stewart kirjoitti:
> Hi there…
>
> Today, we started getting hit with DDOS attacks specifically against our
> CentOS mirror.  Has anyone else seen this behavior before?
>
> These are TCP SYN and TCP RST misuse type attacks.

I don't run a mirror myself, but please note that what you're seeing 
might be simply yum-plugin-fastestmirror doing what's it's supposed to 
do. yum-plugin-fastestmirror determines the closest mirror by opening a 
TCP connection to each mirror and then closing the connection 
immediately. The time spent is measured, and the fastest mirror as 
determined by this process gets selected.