Infrastructure tutorials
Production-grade guides for Linux, servers, security and performance. Copy-paste commands, multi-distro support, written by engineers who run this in production.
Browse by topic
Linux
System administration, shell scripting, package management
Hosting & Servers
Web servers, reverse proxies, SSL, domains
Security
Firewalls, hardening, encryption, access control
Performance
Caching, optimization, profiling, load testing
Databases
MySQL, PostgreSQL, Redis, backups, replication
Networking
DNS, load balancing, VPN, TCP/IP, routing
DevOps
CI/CD, Docker, Kubernetes, automation
Monitoring
Logging, alerting, metrics, observability
Most viewed
Install and configure Deno for web development with systemd and reverse proxy
hostingInstall and configure Caddy web server with automatic HTTPS and reverse proxy
hostingInstall and configure Uvicorn ASGI server with systemd and reverse proxy for FastAPI applications
hostingInstall and configure Ollama for local AI models on Linux servers
devopsInstall and configure Uptime Kuma for website monitoring with SSL and email alerts
monitoringRecently published
Configure custom SNMP MIBs for vendor-specific monitoring with SNMP v2c and v3
monitoringImplement NGINX Plus active health checks for enterprise environments
hostingSetup Prometheus Blackbox Exporter for endpoint monitoring with SSL and alerting
monitoringConfigure Prometheus alerting with AlertManager notifications and webhook integration
monitoringConfigure Elasticsearch cross-cluster replication for disaster recovery
databasesConfigure SSH key authentication and security hardening
Replace password authentication with SSH keys and implement comprehensive security hardening including fail2ban, audit logging, and access controls to protect your Linux servers from unauthorized access and brute force attacks.
Implement two-factor authentication for SSH with Google Authenticator and TOTP
Secure your SSH connections by adding TOTP-based two-factor authentication using Google Authenticator and PAM modules for an additional layer of protection beyond passwords and keys.
Fix SSH sign_and_send_pubkey: signing failed: agent refused operation
Resolve SSH authentication errors when the SSH agent refuses to sign public keys. This tutorial covers checking agent status, fixing key permissions, restarting the agent, and troubleshooting SSH client configuration.
Configure SSH key authentication and disable password login for secure server access
Set up SSH public key authentication on Linux servers and disable password-based logins to prevent brute force attacks and improve security. This tutorial covers key generation, server configuration, and troubleshooting common authentication issues.
Need help?
Don't want to manage this yourself?
We handle infrastructure for businesses that depend on uptime. From initial setup to ongoing operations.
Talk to an engineer