DDoS Protection Methods

DDoS (Distributed Denial of Service) attacks can target your servers and disrupt your services. In this guide, we'll explain in detail how to protect your servers against DDoS attacks.

What is DDoS?

A DDoS attack is a type of cyber attack that aims to make your server or network unavailable through intense traffic from multiple sources. Attackers use networks of infected computers called botnets to overload the target server.

Types of DDoS Attacks

1. Volumetric Attacks

UDP Flood
ICMP Flood
DNS Amplification
NTP Amplification

These attacks exhaust your bandwidth, making the system unusable.

2. Protocol Attacks

SYN Flood
Ping of Death
Smurf Attack

These attacks target server resources or intermediate hardware (firewall, load balancer).

3. Application Layer Attacks

HTTP Flood
Slowloris
DNS Query Flood

These attacks target your web application and consume server resources.

Basic Protection Methods

1. Firewall Configuration

A well-configured firewall is your first line of defense:

bash

# Basic protection with UFW
sudo ufw default deny incoming
sudo ufw default allow outgoing
sudo ufw allow ssh
sudo ufw allow http
sudo ufw allow https
sudo ufw enable

2. Rate Limiting

Rate limiting example with Nginx:

nginx

http {
    limit_req_zone $binary_remote_addr zone=one:10m rate=1r/s;
    
    server {
        location / {
            limit_req zone=one burst=5;
        }
    }
}

3. SYN Cookies

Protection against SYN flood attacks:

bash

# Enable SYN cookies
sudo sysctl -w net.ipv4.tcp_syncookies=1

# Make it permanent
echo "net.ipv4.tcp_syncookies=1" | sudo tee -a /etc/sysctl.conf

Advanced Protection

1. Cloudflare or CDN Usage

CDN services reduce the impact by distributing DDoS attacks:

Cloudflare
AWS CloudFront
Akamai

2. Fail2ban Configuration

Automatic IP blocking with Fail2ban:

bash

# Install Fail2ban
sudo apt install fail2ban

# Configuration
sudo cp /etc/fail2ban/jail.conf /etc/fail2ban/jail.local
sudo nano /etc/fail2ban/jail.local

jail.local example:

ini

[DEFAULT]
bantime = 3600
findtime = 600
maxretry = 5

[sshd]
enabled = true
port = ssh
logpath = /var/log/auth.log

[nginx-limit-req]
enabled = true
port = http,https
logpath = /var/log/nginx/error.log

3. Traffic Monitoring

Real-time traffic monitoring:

bash

# Monitor network traffic with iftop
sudo apt install iftop
sudo iftop -i eth0

# Monitor connections with netstat
netstat -an | grep :80 | wc -l

Adahost DDoS Protection Service

At Adahost, we offer professional DDoS protection services to our customers:

Features

12 Tbps+ Capacity: Absorbs large-scale attacks
Automatic Threat Response: Attacks are automatically detected and blocked
Smart Filtering: Attack traffic is filtered without affecting legitimate users
24/7 Monitoring: Our security team constantly monitors the system
Real-time Reporting: You can see attack details instantly

How It Works?

Traffic Analysis: All incoming traffic is analyzed in real-time
Threat Detection: Abnormal traffic patterns are detected
Automatic Filtering: Attack traffic is automatically blocked
Clean Traffic: Only legitimate traffic reaches your server

What to Do During an Attack

1. Identify the Situation

bash

# Check CPU and memory usage
top

# Check network connections
netstat -an | grep :80 | wc -l

# Check log files
tail -f /var/log/nginx/access.log

2. Emergency Measures

bash

# Block suspicious IPs
sudo iptables -A INPUT -s SUSPICIOUS_IP -j DROP

# Tighten rate limiting
# Lower the rate value in nginx.conf

3. Get Support

In professional DDoS attacks, getting support from your hosting provider is critical. Adahost technical support team is available 24/7.

Preventive Measures

1. Infrastructure Preparation

Scalable Infrastructure: Be ready for sudden traffic spikes
Load Balancing: Distribute load using load balancers
CDN Usage: Serve static content via CDN

2. Application Security

Input Validation: Validate all user inputs
API Rate Limiting: Protect your API endpoints
Cache Usage: Reduce database load

3. Monitoring and Alerting

Uptime Monitoring: Continuously monitor server accessibility
Performance Monitoring: Monitor CPU, RAM, network usage
Alert Setup: Automatically notify abnormal situations

Conclusion

DDoS attacks are serious threats but their impact can be minimized with proper measures. A combination of basic security configurations, professional DDoS protection services, and continuous monitoring can keep your servers safe.

At Adahost, we offer professional DDoS protection service on all our servers. Our customers can activate DDoS protection via the panel and monitor attack statistics in real-time.

The security of your servers is our priority. Our 24/7 technical support team is at your service for any questions or support needs.

DDoS Protection Methods

DDoS Protection Methods

What is DDoS?

Types of DDoS Attacks

1. Volumetric Attacks

2. Protocol Attacks

3. Application Layer Attacks

Basic Protection Methods

1. Firewall Configuration

2. Rate Limiting

3. SYN Cookies

Advanced Protection

1. Cloudflare or CDN Usage

2. Fail2ban Configuration

3. Traffic Monitoring

Adahost DDoS Protection Service

Features

How It Works?

What to Do During an Attack

1. Identify the Situation

2. Emergency Measures

3. Get Support

Preventive Measures

1. Infrastructure Preparation

2. Application Security

3. Monitoring and Alerting

Conclusion

Virtual Server

Dedicated Server

Datacenter

Corporate Information