LYLIX Knowledgebase

ACME without port 80 — DNS-01 challenges for blocked ports and wildcards

The standard Let's Encrypt flow uses HTTP-01: certbot serves a challenge on port 80, the CA fetches it, cert…

Caddy vs nginx vs Traefik — choosing the right reverse proxy

Three reverse proxies cover the vast majority of practical deployments in 2026. Each is best at something specific.…

IPv6-only deployment — when you can skip IPv4 (and when you can't)

IPv4 is exhausted; IPv6 has been ready for decades. Yet the internet remains stubbornly dual-stack because some…

Mail server prerequisites — PTR, SPF, DKIM, DMARC explained

Sending mail from a VPS in 2026 is harder than it used to be — not because the protocols changed, but because…

nftables practical recipes — the UFW alternative for power users

UFW is great for "open SSH, open HTTPS, close everything else." When you need more control — per-source-IP…

Setting reverse DNS (PTR) for your VPS — and why mail servers need it

Reverse DNS — the PTR record — is the lookup that maps an IP address back to a hostname. It's the…

Setting up Let's Encrypt on Debian, AlmaLinux, and Ubuntu — three ways

Let's Encrypt is a free, automated, browser-trusted certificate authority. Three things are needed: a domain…

WireGuard site-to-site between two LYLIX VPSes — config, routing, MTU

WireGuard is the cleanest way to connect two VPSes — or two sites — over an encrypted tunnel.…

Your IP got blacklisted — diagnosing the cause and rotating to a clean IP

An IP that ends up on a public blocklist hurts in different ways depending on what you use the VPS for: outbound…

Networking & DNS