Fortigate Vm Sizing Azure May 2026

Apply these reference rules based on your expected traffic and enabled features.

| Mistake | Consequence | Fix | | :--- | :--- | :--- | | Using B-series VMs | Dropped packets after CPU credit exhaustion | Switch to D or F series. | | Pairing 8‑vCPU VM with VM04 license | Wasted Azure cost, no performance gain | Match vCPUs to license tier. | | Forgetting SSL inspection overhead | Throughput drops 80% unexpectedly | Double vCPUs from raw baseline. | | Deploying single VM for critical path | No HA, Azure host maintenance causes outage | A-P pair + Azure LB or FortiGate FGCP. | fortigate vm sizing azure

Before selecting an Azure VM size, you must understand Fortinet’s licensing model. FortiGate-VM licenses are tied to the number of vCPUs provisioned in Azure, not the VM memory or clock speed. Apply these reference rules based on your expected

| License Tier | vCPUs (Azure) | Typical Raw Throughput* | Use Case | | :--- | :--- | :--- | :--- | | FG-VM02 | 2 | ~1 Gbps | Dev/Test, branch office | | FG-VM04 | 4 | ~2-4 Gbps | Small production, DMZ | | FG-VM08 | 8 | ~4-8 Gbps | Mid-size enterprise | | FG-VM16 | 16 | ~8-16 Gbps | Large hub, heavy inspection | Critical rule: If you assign an 8‑vCPU Azure

*Throughput varies dramatically with features (SSL inspection, IPS, threat protection).

Critical rule: If you assign an 8‑vCPU Azure VM but purchase only a VM04 license, the FortiGate will only use 4 vCPUs. Right-size both the Azure VM and the license.