Fortigate Vm Sizing Azure [best] Review

For sizing a FortiGate-VM on Microsoft Azure, the most critical factor is aligning your vCPU count with your Fortinet license (BYOL) or choosing an Azure instance family that maximizes throughput and network interface (NIC) support . Core Sizing Recommendations

Mistake #2: Ignoring East-West Traffic

• Why it fails: You size for internet ingress (2 Gbps) but forget that your Azure VMs send 5 Gbps between subnets – all inspected.
• Fix: Use Azure Network Watcher for 7 days to capture intra-VNet traffic. Add 100% buffer.

Need a sizing spreadsheet? Fortinet offers a free “Azure Sizing Calculator” on their support portal. Or, use the open-source fortinet-sizer tool on GitHub. fortigate vm sizing azure

| VM Size | Max Network Bandwidth (Gbps) | FortiGate Realistic Inspection Throughput | |---------|------------------------------|--------------------------------------------| | D2s v3 | ~1.5 Gbps | ~0.8 Gbps (with basic firewall) | | D4s v3 | ~3.0 Gbps | ~1.5-2 Gbps (with IPS) | | D8s v3 | ~6.0 Gbps | ~3 Gbps (with SSL inspection) | | D16s v3 | ~12.0 Gbps | ~5-6 Gbps (mixed traffic) | For sizing a FortiGate-VM on Microsoft Azure ,

References and further reading

Part 3: Choosing the Right Azure Instance Family

Not all Azure VMs behave the same. FortiGate is sensitive to three things: CPU stability, network PPS (packets per second), and memory bandwidth. Why it fails: You size for internet ingress