Donaldson R F
Servers & Hosting (Plesk, CloudPanel, Linux)
Configure Fail2Ban & Linux Firewall
Set up Fail2Ban and firewall rules to automatically block brute-force and scanning attempts.
The Problem
Your server logs are full of repeated failed login attempts from the same IPs, and without Fail2Ban and proper firewall rules, nothing is actually stopping them from trying forever.
About this problem
Server logs filling with repeated failed login attempts from the same handful of IPs is completely normal background noise on the internet — automated bots scan ranges constantly. Without Fail2Ban actively banning those IPs after a few failures, nothing is actually stopping them from trying indefinitely, which is both a resource drain and a standing risk if a weak credential ever gets guessed.
This usually comes up after someone actually looks at their auth logs for the first time and is alarmed by the volume of attempts.
What's Included
- Installing and configuring Fail2Ban with jails for SSH and any other exposed services
- Tuning ban thresholds and durations sensibly
- Setting up firewall rules (UFW/iptables) to match what's actually meant to be public
- Verifying bans trigger correctly with a real test
What's NOT Included
- Fixing an active intrusion (different from blocking future attempts)
- DDoS protection — Fail2Ban doesn't help against volumetric attacks
- Ongoing log monitoring
How It Works
- Review current log activity to confirm the scale and pattern of repeated login attempts.
- Install and configure Fail2Ban with jails for SSH and any other exposed services (mail, panel logins).
- Tune ban thresholds and durations to balance security against accidentally locking out legitimate users.
- Set up firewall rules (UFW/iptables) matching exactly what's meant to be publicly reachable.
- Trigger a real test ban to confirm the configuration actually blocks as expected.
In practice: you buy the service, send over whatever access or details the job needs, I investigate and do the work, and you confirm it's resolved before we call it done.
Frequently Asked Questions
- Is it normal to see hundreds of failed SSH login attempts in my logs?
- Yes, this is standard background internet noise from automated scanning bots — it doesn't mean you're specifically targeted, but it does mean Fail2Ban is worth having active.
- What does Fail2Ban actually do?
- It watches log files for repeated failed login patterns and automatically adds a temporary (or permanent) firewall block for the offending IP after a configured number of attempts.
- Can Fail2Ban protect services other than SSH?
- Yes, jails can be configured for mail servers, web panel logins, and various other services that log failed authentication attempts.
- Will Fail2Ban accidentally block me if I mistype my password?
- Thresholds are tuned to allow a few genuine mistakes before banning, balancing real protection against accidental lockouts — the exact threshold is adjustable.
- Does Fail2Ban stop DDoS attacks?
- No — it's designed for brute-force login attempts, not volumetric traffic attacks, which need different mitigation entirely.
- How do I unban my own IP if Fail2Ban blocks me by mistake?
- Via server console access (bypassing SSH) you can remove the ban directly — this is worth knowing before hardening, in case you ever lock yourself out.