ClamAV Installation Guide Installation Guide

ClamAV is a free and open-source Antivirus. Open source antivirus engine

Hardware Requirements:

CPU: 2 cores minimum (4+ cores recommended)

RAM: 2GB minimum (4GB+ recommended)

Storage: 1GB for installation

Network: 3310 ports

Operating System:

Linux: Any modern distribution (RHEL, Debian, Ubuntu, CentOS, Fedora, Arch, Alpine, openSUSE)

macOS: 10.14+ (Mojave or newer)

Windows: Windows Server 2016+ or Windows 10

FreeBSD: 11.0+

Network Requirements:

Port 3310 (default clamav port)

Dependencies:

clamav-freshclam, clamav-update

System Access: root or sudo privileges required

This guide supports installation on:

RHEL 8/9 and derivatives (CentOS Stream, Rocky Linux, AlmaLinux)

Debian 11/12

Ubuntu 20.04/22.04/24.04 LTS

Arch Linux (rolling release)

Alpine Linux 3.18+

openSUSE Leap 15.5+ / Tumbleweed

SUSE Linux Enterprise Server (SLES) 15+

macOS 12+ (Monterey and later)

FreeBSD 13+

Windows 10/11/Server 2019+ (where applicable)

bash

# Install EPEL repository if needed
sudo dnf install -y epel-release

# Install clamav
sudo dnf install -y clamav clamav-freshclam, clamav-update

# Enable and start service
sudo systemctl enable --now clamav-daemon

# Configure firewall
sudo firewall-cmd --permanent --add-service=clamav
sudo firewall-cmd --reload

# Verify installation
clamav --version || systemctl status clamav-daemon

bash

# Update package index
sudo apt update

# Install clamav
sudo apt install -y clamav clamav-freshclam, clamav-update

# Enable and start service
sudo systemctl enable --now clamav-daemon

# Configure firewall
sudo ufw allow 3310

# Verify installation
clamav --version || systemctl status clamav-daemon

bash

# Install clamav
sudo pacman -S clamav

# Enable and start service
sudo systemctl enable --now clamav-daemon

# Verify installation
clamav --version || systemctl status clamav-daemon

bash

# Install clamav
apk add --no-cache clamav

# Enable and start service
rc-update add clamav-daemon default
rc-service clamav-daemon start

# Verify installation
clamav --version || rc-service clamav-daemon status

bash

# Install clamav
sudo zypper install -y clamav clamav-freshclam, clamav-update

# Enable and start service
sudo systemctl enable --now clamav-daemon

# Configure firewall
sudo firewall-cmd --permanent --add-service=clamav
sudo firewall-cmd --reload

# Verify installation
clamav --version || systemctl status clamav-daemon

bash

# Using Homebrew
brew install clamav

# Start service
brew services start clamav

# Verify installation
clamav --version

bash

# Using pkg
pkg install clamav

# Enable in rc.conf
echo 'clamav-daemon_enable="YES"' >> /etc/rc.conf

# Start service
service clamav-daemon start

# Verify installation
clamav --version || service clamav-daemon status

powershell

# Using Chocolatey
choco install clamav

# Or using Scoop
scoop install clamav

# Verify installation
clamav --version

bash

# Create configuration directory if needed
sudo mkdir -p /etc/clamav

# Set up basic configuration
sudo tee /etc/clamav/clamav.conf << 'EOF'
# ClamAV Configuration
MaxThreads 12, MaxConnectionQueueLength 30
EOF

# Test configuration
sudo clamav -t || sudo clamav-daemon configtest

# Reload service
sudo systemctl reload clamav-daemon

bash

# Set appropriate permissions
sudo chown -R clamav:clamav /etc/clamav
sudo chmod 750 /etc/clamav

# Enable security features
# See security section for detailed hardening steps

bash

# Enable service
sudo systemctl enable clamav-daemon

# Start service
sudo systemctl start clamav-daemon

# Stop service
sudo systemctl stop clamav-daemon

# Restart service
sudo systemctl restart clamav-daemon

# Reload configuration
sudo systemctl reload clamav-daemon

# Check status
sudo systemctl status clamav-daemon

# View logs
sudo journalctl -u clamav-daemon -f

bash

# Enable service
rc-update add clamav-daemon default

# Start service
rc-service clamav-daemon start

# Stop service
rc-service clamav-daemon stop

# Restart service
rc-service clamav-daemon restart

# Check status
rc-service clamav-daemon status

bash

# Enable in /etc/rc.conf
echo 'clamav-daemon_enable="YES"' >> /etc/rc.conf

# Start service
service clamav-daemon start

# Stop service
service clamav-daemon stop

# Restart service
service clamav-daemon restart

# Check status
service clamav-daemon status

bash

# Using Homebrew services
brew services start clamav
brew services stop clamav
brew services restart clamav

# Check status
brew services list | grep clamav

powershell

# Start service
net start clamav-daemon

# Stop service
net stop clamav-daemon

# Using PowerShell
Start-Service clamav-daemon
Stop-Service clamav-daemon
Restart-Service clamav-daemon

# Check status
Get-Service clamav-daemon

bash

# Configure performance settings
cat >> /etc/clamav/clamav.conf << 'EOF'
MaxThreads 12, MaxConnectionQueueLength 30
EOF

# Apply system tuning
sudo sysctl -w net.core.somaxconn=65535
sudo sysctl -w net.ipv4.tcp_max_syn_backlog=65535

# Restart service
sudo systemctl restart clamav-daemon

bash

# Configure clustering (if supported)
# See official documentation for cluster setup

# Basic load balancing setup example
# Configure multiple instances on different ports

nginx

upstream clamav_backend {
    server 127.0.0.1:3310;
    server 127.0.0.1:{default_port}1 backup;
}

server {
    listen 80;
    server_name clamav.example.com;
    return 301 https://$server_name$request_uri;
}

server {
    listen 443 ssl http2;
    server_name clamav.example.com;

    ssl_certificate /etc/ssl/certs/clamav.example.com.crt;
    ssl_certificate_key /etc/ssl/private/clamav.example.com.key;

    location / {
        proxy_pass http://clamav_backend;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        
        # WebSocket support (if needed)
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
    }
}

apache

<VirtualHost *:80>
    ServerName clamav.example.com
    Redirect permanent / https://clamav.example.com/
</VirtualHost>

<VirtualHost *:443>
    ServerName clamav.example.com
    
    SSLEngine on
    SSLCertificateFile /etc/ssl/certs/clamav.example.com.crt
    SSLCertificateKeyFile /etc/ssl/private/clamav.example.com.key
    
    ProxyRequests Off
    ProxyPreserveHost On
    
    ProxyPass / http://127.0.0.1:3310/
    ProxyPassReverse / http://127.0.0.1:3310/
    
    # WebSocket support (if needed)
    RewriteEngine on
    RewriteCond %{HTTP:Upgrade} websocket [NC]
    RewriteCond %{HTTP:Connection} upgrade [NC]
    RewriteRule ^/?(.*) "ws://127.0.0.1:3310/$1" [P,L]
</VirtualHost>

haproxy

frontend clamav_frontend
    bind *:80
    bind *:443 ssl crt /etc/ssl/certs/clamav.pem
    redirect scheme https if !{ ssl_fc }
    default_backend clamav_backend

backend clamav_backend
    balance roundrobin
    option httpchk GET /health
    server clamav1 127.0.0.1:3310 check
    server clamav2 127.0.0.1:{default_port}1 check backup

bash

# Set appropriate permissions
sudo chown -R clamav:clamav /etc/clamav
sudo chmod 750 /etc/clamav

# Configure firewall
sudo firewall-cmd --permanent --add-service=clamav
sudo firewall-cmd --reload

# Enable SELinux policies (if applicable)
sudo setsebool -P httpd_can_network_connect on

# Configure fail2ban
sudo tee /etc/fail2ban/jail.d/clamav.conf << 'EOF'
[clamav]
enabled = true
port = 3310
filter = clamav
logpath = /var/log/clamav/*.log
maxretry = 5
bantime = 3600
EOF

bash

# Generate SSL certificates
sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 \
    -keyout /etc/ssl/private/clamav.key \
    -out /etc/ssl/certs/clamav.crt

# Configure SSL in clamav
# See official documentation for SSL configuration

PostgreSQL Backend (if applicable)

bash

# Create database and user
sudo -u postgres psql << EOF
CREATE DATABASE clamav_db;
CREATE USER clamav_user WITH ENCRYPTED PASSWORD 'secure_password';
GRANT ALL PRIVILEGES ON DATABASE clamav_db TO clamav_user;
EOF

# Configure clamav to use PostgreSQL
# See official documentation for database configuration

bash

# Create database and user
sudo mysql << EOF
CREATE DATABASE clamav_db;
CREATE USER 'clamav_user'@'localhost' IDENTIFIED BY 'secure_password';
GRANT ALL PRIVILEGES ON clamav_db.* TO 'clamav_user'@'localhost';
FLUSH PRIVILEGES;
EOF

bash

# Kernel parameters
sudo tee -a /etc/sysctl.conf << EOF
net.core.somaxconn = 65535
net.ipv4.tcp_max_syn_backlog = 65535
net.ipv4.ip_local_port_range = 1024 65535
net.core.netdev_max_backlog = 5000
vm.swappiness = 10
EOF

sudo sysctl -p

# ClamAV specific tuning
MaxThreads 12, MaxConnectionQueueLength 30

bash

# Configure system limits
sudo tee -a /etc/security/limits.conf << EOF
clamav soft nofile 65535
clamav hard nofile 65535
clamav soft nproc 32768
clamav hard nproc 32768
EOF

yaml

# prometheus.yml configuration
scrape_configs:
  - job_name: 'clamav'
    static_configs:
      - targets: ['localhost:3310']
    metrics_path: '/metrics'

bash

# Basic health check script
#!/bin/bash
if systemctl is-active --quiet clamav-daemon; then
    echo "ClamAV is running"
    exit 0
else
    echo "ClamAV is not running"
    exit 1
fi

bash

# Configure log rotation
sudo tee /etc/logrotate.d/clamav << 'EOF'
/var/log/clamav/*.log {
    daily
    rotate 14
    compress
    delaycompress
    missingok
    notifempty
    create 0640 clamav clamav
    postrotate
        systemctl reload clamav-daemon > /dev/null 2>&1 || true
    endscript
}
EOF

bash

#!/bin/bash
# ClamAV backup script
BACKUP_DIR="/backup/clamav"
DATE=$(date +%Y%m%d_%H%M%S)

mkdir -p "$BACKUP_DIR"

# Stop service (if required)
systemctl stop clamav-daemon

# Backup configuration
tar -czf "$BACKUP_DIR/clamav-config-$DATE.tar.gz" /etc/clamav

# Backup data (adjust paths as needed)
tar -czf "$BACKUP_DIR/clamav-data-$DATE.tar.gz" /var/lib/clamav

# Start service
systemctl start clamav-daemon

# Clean old backups (keep 30 days)
find "$BACKUP_DIR" -name "*.tar.gz" -mtime +30 -delete

echo "Backup completed: $BACKUP_DIR"

bash

# Stop service
sudo systemctl stop clamav-daemon

# Restore configuration
sudo tar -xzf /backup/clamav/clamav-config-*.tar.gz -C /

# Restore data
sudo tar -xzf /backup/clamav/clamav-data-*.tar.gz -C /

# Set permissions
sudo chown -R clamav:clamav /etc/clamav
sudo chown -R clamav:clamav /var/lib/clamav

# Start service
sudo systemctl start clamav-daemon

1. Service won't start:

bash

# Check logs
sudo journalctl -u clamav-daemon -n 100
sudo tail -f /var/log/clamav/*.log

# Check configuration
sudo clamav -t || sudo clamav-daemon configtest

# Check permissions
ls -la /etc/clamav
ls -la /var/lib/clamav

2. Connection refused:

bash

# Check if service is listening
sudo ss -tlnp | grep 3310
sudo netstat -tlnp | grep 3310

# Check firewall
sudo firewall-cmd --list-all
sudo iptables -L -n

# Test connection
telnet localhost 3310
nc -zv localhost 3310

3. Performance issues:

bash

# Check resource usage
top -p $(pgrep clamd)
htop -p $(pgrep clamd)

# Check connections
ss -ant | grep :3310 | wc -l

# Monitor I/O
iotop -p $(pgrep clamd)

bash

# Run in debug mode
sudo clamav -d
# or
sudo clamav-daemon debug

# Increase log verbosity
# Edit configuration to enable debug logging

yaml

version: '3.8'
services:
  clamav:
    image: clamav:latest
    container_name: clamav
    ports:
      - "3310:3310"
    volumes:
      - ./config:/etc/clamav
      - ./data:/var/lib/clamav
    environment:
      - clamav_CONFIG=/etc/clamav/clamav.conf
    restart: unless-stopped
    networks:
      - clamav_net

networks:
  clamav_net:
    driver: bridge

yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: clamav
spec:
  replicas: 3
  selector:
    matchLabels:
      app: clamav
  template:
    metadata:
      labels:
        app: clamav
    spec:
      containers:
      - name: clamav
        image: clamav:latest
        ports:
        - containerPort: 3310
        volumeMounts:
        - name: config
          mountPath: /etc/clamav
      volumes:
      - name: config
        configMap:
          name: clamav-config
---
apiVersion: v1
kind: Service
metadata:
  name: clamav
spec:
  selector:
    app: clamav
  ports:
  - port: 3310
    targetPort: 3310
  type: LoadBalancer

yaml

---
- name: Install and configure ClamAV
  hosts: all
  become: yes
  tasks:
    - name: Install clamav
      package:
        name: clamav
        state: present
    
    - name: Configure clamav
      template:
        src: clamav.conf.j2
        dest: /etc/clamav/clamav.conf
        owner: clamav
        group: clamav
        mode: '0640'
      notify: restart clamav
    
    - name: Start and enable clamav
      systemd:
        name: clamav-daemon
        state: started
        enabled: yes
  
  handlers:
    - name: restart clamav
      systemd:
        name: clamav-daemon
        state: restarted

Maintenance

bash

# RHEL/CentOS/Rocky/AlmaLinux
sudo dnf update clamav

# Debian/Ubuntu
sudo apt update && sudo apt upgrade clamav

# Arch Linux
sudo pacman -Syu clamav

# Alpine Linux
apk update && apk upgrade clamav

# openSUSE
sudo zypper update clamav

# FreeBSD
pkg update && pkg upgrade clamav

# Always backup before updates
tar -czf /backup/clamav-pre-update-$(date +%Y%m%d).tar.gz /etc/clamav

# Restart after updates
sudo systemctl restart clamav-daemon

Regular Maintenance Tasks

bash

# Clean logs
find /var/log/clamav -name "*.log" -mtime +30 -delete

# Verify integrity
sudo clamav --verify || sudo clamav-daemon check

# Update databases (if applicable)
sudo clamav-update-db

# Optimize performance
sudo clamav-optimize

# Check for security updates
sudo clamav --security-check

Official Documentation: https://docs.clamav.org/

GitHub Repository: https://github.com/clamav/clamav

Community Forum: https://forum.clamav.org/

Wiki: https://wiki.clamav.org/

Comparison vs Sophos, ESET, Kaspersky, Bitdefender: https://docs.clamav.org/comparison

---

Note: This guide is part of the HowToMgr collection. Always refer to official documentation for the most up-to-date information.

1. Prerequisites

2. Supported Operating Systems

3. Installation

RHEL/CentOS/Rocky Linux/AlmaLinux

Debian/Ubuntu

Arch Linux

Alpine Linux

openSUSE/SLES

macOS

FreeBSD

Windows

Initial Configuration

Basic Configuration

Security Hardening

5. Service Management

systemd (RHEL, Debian, Ubuntu, Arch, openSUSE)

OpenRC (Alpine Linux)

rc.d (FreeBSD)

launchd (macOS)

Windows Service Manager

Advanced Configuration

Performance Optimization

Clustering and High Availability

Reverse Proxy Setup

nginx Configuration

Apache Configuration

HAProxy Configuration

Security Configuration

Basic Security Setup

SSL/TLS Configuration

Database Setup

PostgreSQL Backend (if applicable)

MySQL/MariaDB Backend (if applicable)

Performance Optimization

System Tuning

Resource Limits

Monitoring

Prometheus Integration

Health Checks

Log Monitoring

9. Backup and Restore

Backup Script

Restore Procedure

6. Troubleshooting

Common Issues

Debug Mode

Integration Examples

Docker Compose

Kubernetes Deployment

Ansible Playbook

Maintenance

Update Procedures

Regular Maintenance Tasks

Additional Resources