Linux Server Security
Brute-Force Protection
Brute-force bots hammer SSH, FTP, WordPress logins, and webmail around the clock. Layered brute-force protection, fail2ban jails, cPHulk, rate limiting, and strong credential policy, turns millions of guesses into background noise instead of successful logins.
Key points
- Deploy fail2ban jails for sshd, pure-ftpd, dovecot, exim, and cpaneld with escalating bantimes.
- Enable cPHulk with country-level blocking for cPanel, WHM, and webmail logins.
- Rate-limit wp-login.php and xmlrpc.php at the web server or WAF layer.
- Enforce 16+ character generated passwords and password-manager usage for all accounts.
- Add CAPTCHA or proof-of-work on public login forms after 2 failures.
- Monitor ban volumes: sudden spikes often precede targeted campaigns.
- Expire and rotate credentials on staff changes without exception.
- Combine with 2FA wherever the login flow supports it.
Field note
Watch ban volumes, not just bans. A quiet server that suddenly bans ten times its baseline is telling you a campaign started, that signal is worth more than any single blocked IP.
Frequently asked questions
How many login attempts are normal per day?
Internet-facing SSH routinely sees thousands; WordPress logins hundreds. Zero successful unknown logins is the only acceptable number.
Does banning IPs hurt legitimate users?
Short escalating bans rarely do. Permanent blocks are reserved for repeat offenders and hostile networks.
Is CAPTCHA enough by itself?
No, it slows bots but doesn't replace server-side throttling, bans, and strong credentials.
What about distributed slow attacks?
These need behavioral detection (many IPs, one account) rather than per-IP limits, part of managed monitoring.
How Kinetikatech helps with linux server security
You shouldn't have to become an expert in linux server security: Hardening, monitoring, and defending CloudLinux, Rocky Linux, and cPanel servers against malware, brute force, and intrusions, 24/7. That's exactly what Linux Server Security and Server Management is for, setup, hardening, monitoring, and a human on call day and night.