mod_evasive adalah modul untuk Apache untuk memberikan tindakan mengelak dari aktivitas HTTP DoS atau serangan DDoS atau serangan brute force. Hal ini juga dirancang untuk menjadi alat deteksi dan manajemen jaringan, dan dapat dengan mudah dikonfigurasi untuk dikolaborasikan dengan ipchains, firewall, router, dan sebagainya. mod_evasive bisa memberikan laporan pelanggaran melalui email dan fasilitas syslog.
Saya akan coba memberikan langkah-langkah untuk instalasi mod_evasive pada server yang menggunakan cPanel.
Download & Instalasi
cd /usr/local/src
wget http://www.zdziarski.com/blog/wp-content/uploads/2010/02/mod_evasive_1.10.1.tar.gz
tar xzf mod_evasive_1.10.1.tar.gz
cd mod_evasive
apxs -cia mod_evasive20.c
/usr/local/cpanel/bin/apache_conf_distiller --update
Konfigurasi
Tambahkan kode dibawah ini pada file /usr/local/apache/conf/includes/post_virtualhost_2.conf bisa lewar console/ssh atau lewat WHM. Apache Configuration > Include Editor -> Post VirtualHost Include (pilih versi 2.2.xx).
LoadModule evasive20_module modules/mod_evasive20.so
<IfModule mod_evasive20.c>
DOSHashTableSize 3097
DOSPageCount 2
DOSSiteCount 50
DOSPageInterval 1
DOSSiteInterval 1
DOSBlockingPeriod 3600
</IfModule>
Lakukan pengecekan konfigurasi apache dengan perintah service httpd configtest sebelum apache anda restart.
Selamat mencoba ..
--
Berikut informasi detil mengenai mod_evasive :
What is mod_evasive?
mod_evasive is an evasive maneuvers module for Apache to provide evasive action in the event of an HTTP DoS or DDoS attack or brute force attack. It is also designed to be a detection and network management tool, and can be easily configured to talk to ipchains, firewalls, routers, and etcetera. mod_evasive presently reports abuses via email and syslog facilities.
Detection is performed by creating an internal dynamic hash table of IP Addresses and URIs, and denying any single IP address from any of the following:
- Requesting the same page more than a few times per second
- Making more than 50 concurrent requests on the same child per second
- Making any requests while temporarily blacklisted (on a blocking list)
This method has worked well in both single-server script attacks as well as distributed attacks, but just like other evasive tools, is only as useful to the point of bandwidth and processor consumption (e.g. the amount of bandwidth and processor required to receive/process/respond to invalid requests), which is why it’s a good idea to integrate this with your firewalls and routers for maximum protection.
This module instantiates for each listener individually, and therefore has a built-in cleanup mechanism and scaling capabilities. Because of this per-child design, legitimate requests are never compromised (even from proxies and NAT addresses) but only scripted attacks. Even a user repeatedly clicking on ‘reload’ should not be affected unless they do it maliciously. mod_evasive is fully tweakable through the Apache configuration file, easy to incorporate into your web server, and easy to use.
referensi:
- http://www.zdziarski.com/blog/?page_id=442