Secure Your Linux Servers

By admin • General

Server security is paramount. A compromised server can lead to data breaches, downtime, and financial losses. This guide covers essential steps to secure your Linux servers.

1. Keep the System Updated

# CentOS/RHEL
yum update -y
# Ubuntu/Debian
apt-get update && apt-get upgrade -y

2. Configure SSH Security

# /etc/ssh/sshd_config
PermitRootLogin no
PasswordAuthentication no
Port 2222
AllowUsers myuser

3. Configure Firewall

iptables -A INPUT -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j ACCEPT
iptables -A INPUT -j DROP

4. Install Fail2Ban

Fail2Ban monitors logs and blocks IPs with too many failed login attempts.

yum install fail2ban
service fail2ban start

5. Disable Unnecessary Services

chkconfig sendmail off
chkconfig avahi-daemon off