Technical solutions and approaches from real projects.
Anti-spoofing, cryptographic signing and policy, with DNS verification.
Primary + standby, pg_basebackup, lag verification and failover.
Frontend/backend, algorithms, health checks, TLS and a stats page.
ed25519 keys, no password/root, 2FA, jump host and brute-force protection.
Wildcard *.domain without port 80 (Cloudflare), ideal for intranet, with auto-renewal.
Install, acquisition, collections, nftables bouncer, console and testing β step by step.
Dedicated migration network, bonding/VLAN, online migration and CPU compatibility.
Mirror/raidz pool, compression, instant snapshots and node-to-node replication.
Incremental, deduplicated backup with integrity verification and retention β step by step.
Ceph, StarWind VSAN Free, GlusterFS, DRBD/Linstor, ZFS β comparison and when to choose each.
IDS/IPS, SIEM, threat intelligence, feeds, firewall, VPN, scanning and monitoring β listed with what each does.
Proxmox VE cluster with replicated Ceph storage: requirements, network, OSDs, RBD pool and High Availability.
WireGuard server on Debian plus setting up the client on Windows, step by step.
Base ruleset, IP sets, SSH rate-limit, logging and persistence β commands.
Install, firewall, server block and Let's Encrypt TLS β Debian 12/13.
Practical guide: containerized apps with Docker behind an Nginx reverse proxy, Let's Encrypt TLS, isolated networks and production hardening.
Practical guide: OPNsense firewall with inline Suricata IDS/IPS and collaborative CrowdSec IPS β install, rules, tuning and testing.
Two locations as one L2 network (OpenVPN bridge per VLAN), dual-ISP with instant failover, security (Suricata, ipset, GeoIP, nftables, Fail2ban), KVM and a backup server that takes over in 15 minutes.
A client with 20+ web apps across 5 VMs and 2 dedicated servers, consolidated onto a single Debian server with KVM: 3 VMs, security with nginx + GeoIP + Suricata, Zabbix monitoring and image-level backup.
RAID10 array with 6 out of 10 disks offline and a crashed Oracle database. How we brought the controller back, rebuilt the array, and recovered the database from redo logs β zero critical data loss.
Why Debian remains the preferred Linux distribution for enterprise servers in 2026.
Which firewall fits SMB, mid-market or enterprise in 2026.
After Broadcom price hikes, many migrate. Step-by-step VMware β Proxmox VE migration guide.
How to secure a Linux Debian server in 2026 β CIS benchmark, fail2ban, GeoIP, CrowdSec.
How to implement backup and DR with Veeam B&R using the 3-2-1 strategy.
SD-WAN implementation with FortiGate: link load balancing, application steering, ZTNA, what it involves.
P2V conversion of physical Windows/Linux server to Hyper-V: phases, challenges, architectural decisions.
Enterprise firewall on Linux: nftables, GeoIP, IP reputation, fail2ban, NetFlow visibility.
Build a functional 24/7 SOC with Wazuh, Suricata and Grafana β open-source enterprise-grade stack.
HA reverse proxy layer design with HAProxy, Nginx, ModSecurity WAF, automatic SSL.
Why and how to implement self-hosted mail server with Postfix, Dovecot, Rspamd, DKIM/SPF/DMARC.
Complete monitoring stack: infrastructure, network, apps, business metrics, centralized logs.
Ansible implementation: playbooks, dynamic inventory, vault, AWX.