Grenzer replaces CSF with a firewall and login-failure detection engine built for 2026 — nftables-native, written in Go, free forever. Upgrade to Pro when you need AI detection, backup, and cPanel integration.
curl -fsSL https://raw.githubusercontent.com/Dpro-at/grenzer-releases/main/scripts/install.sh | bash
The core is free forever. Pro adds the tooling professional teams and hosting companies actually ask for.
A modern rule engine generated and managed by Go — no legacy iptables shell-outs, no Perl.
FreeReal-time brute-force detection with automatic, self-expiring temp bans — the daily driver from CSF, rebuilt.
FreeAn async LLM layer reviews ambiguous activity in the background — never blocking in the hot path, always optional.
ProConnect Claude, Cursor, or any MCP-compatible AI directly to your server's live security data and controls.
ProPer-tenant, encrypted, checksummed backups to any S3-compatible destination — restore one account without touching another.
ProGrenzer status and controls surfaced right inside the site owner's own cPanel — built for hosting companies and agencies.
ProCSF hasn't fundamentally changed in years. Here's what's different, tier by tier.
| Capability | CSF | Grenzer Free | Grenzer Pro |
|---|---|---|---|
| Firewall engine | iptables | nftables | nftables |
| Login Failure Detection | |||
| AI-augmented detection | — | — | |
| MCP / AI assistant integration | — | — | |
| Multi-tenant backup | — | — | |
| cPanel / WHM plugin | limited | — | |
| Price | free | free | $192 / year |
One server, one price. No seat counting, no surprise tiers.
Pro checkout is handled by Stripe. Card details never touch Grenzer's servers.