Multi-firewall Proxmox lab network with three-tier firewall architecture (FW-1, FW-2, FW-3) segmenting internal virtual networks and external internet access. Traffic flows from Internet through gateway (144.76.111.1/27) to Proxmox host (vmbr0), then through firewall chain to isolated subnets including GOAD, Kali-Linux, and multiple virtual bridges (vmbr10–vmbr32) spanning 10.x and 192.168.x ranges. This architecture demonstrates network segmentation and defense-in-depth principles for penetration testing and security research labs. Fork and customize this diagram on Diagrams.so to adapt firewall rules, add additional VLANs, or document your own Proxmox infrastructure. The design isolates attack surfaces while maintaining controlled connectivity between lab components.