Fortigate Vm Sizing Azure
Azure VM networking has a cumulative limit – all NICs share the same underlying bandwidth.
| 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) |
Heuristic: For full UTM (IPS + SSL + AV), expect 40-50% of the VM’s raw network bandwidth.
Mandatory. Without it, you lose SR-IOV, and throughput drops by >70%.
Do not use burstable (B-series) for production workloads. Use general purpose or memory-optimized families.
Migrating from a physical firewall appliance to a virtual firewall in Microsoft Azure is not a simple 1:1 core-to-core replacement. In the physical world, sizing was governed by ASIC acceleration and fixed port speeds. In Azure, your FortiGate VM (Fortinet’s Virtual Next-Generation Firewall) runs on shared or dedicated infrastructure, where CPU credits, RAM speed, and network latency are dynamic variables.
Incorrect sizing is the leading cause of cloud network failure. An undersized FortiGate leads to packet drops, high latency, and VPN reconnections. An oversized VM wastes hundreds or thousands of dollars per month on idle vCPUs.
This 3,000+ word guide will walk you through the anatomy of FortiGate VM sizing in Azure, covering SKU selection, throughput calculations, licensing models, high availability (HA) implications, and real-world deployment patterns.
Sizing a FortiGate VM on Azure requires balancing three critical factors: FortiOS license limits, Azure VM NIC limits, and your performance throughput needs. 1. Determining the Minimum Size
While FortiOS can run on small instances, enable at least 4 GB of RAM for proper operation, especially if you plan to use UTM (Unified Threat Management) or Proxy features.
NIC Constraints: A common "gotcha" is that Azure limits the number of Network Interface Cards (NICs) based on VM size. For a standard Active-Passive HA setup, you typically need at least 4 NICs (Management, Untrust, Trust, HA sync).
Minimum for 4 NICs: You generally need at least an 8-vCPU instance like the Standard_F8s_v2 or Standard_D3_v2 to support 4 network interfaces.
Version-Specific IPS: Starting with FortiOS 7.4.0, if you want to use the full "extended IPS database," Fortinet recommends a minimum of 8 vCPUs. 2. Recommended Azure Instance Families Best Use Case Recommended Models F-Series (Compute Optimized)
High throughput, IPS, and SSL inspection. Often the best price-to-performance ratio for firewalls. Standard_F4s_v2, Standard_F8s_v2 D-Series (General Purpose)
Balanced workloads or when more RAM is needed for heavy logging/reporting. Standard_D2s_v5, Standard_D4s_v5 3. Licensing vs. Azure Size
In public clouds, Fortinet licensing only restricts the number of vCPUs you can use.
The VM size determines the number of ______ that you can create for a VM
Sizing Your FortiGate VM in Azure: A Comprehensive Guide Deploying a FortiGate Next-Generation Firewall (NGFW)
on Microsoft Azure is a powerful way to secure your cloud workloads. However, unlike physical appliances with fixed specs, "sizing" in the cloud is a balancing act between Azure instance limits Fortinet licensing
This guide breaks down how to choose the right VM size to ensure peak performance without overspending.
1. The Two Pillars of Sizing: Azure SKU vs. FortiGate License
When you size a FortiGate VM, you must satisfy two different sets of constraints: Azure Instance Limits: Each Azure VM size (e.g., Standard_F4s ) has a hard cap on the number of Network Interfaces (NICs) and raw CPU/RAM. FortiGate License Limits: If you use Bring Your Own License (BYOL) , your license (e.g.,
) limits how many vCPUs the FortiOS software will actually use.
You can run a 2-vCPU license on an 8-vCPU Azure VM if you need more NICs, but the FortiGate will only use 2 of those CPUs for traffic processing. 2. Recommended Azure Instance Families For security appliances, Fortinet generally recommends Compute-Optimized General-Purpose instances.
Sizing a FortiGate-VM in Azure requires balancing Azure's virtual machine performance with Fortinet's licensing tiers. Because Azure throttles network throughput based on the instance size, choosing a VM with enough vCPUs and RAM is critical for security performance. 1. Minimum Requirements
While a FortiGate-VM can technically run on 1 vCPU and 2 GB of RAM, these specs are generally reserved for evaluation or light testing.
Recommended Minimum: At least 4 GB of RAM is recommended for stable operation, especially if you enable features like Unified Threat Management (UTM), Zero Trust Network Access (ZTNA), or Proxy.
Storage: Most deployments start with 32 GB of disk space, expandable up to 2 TB for logging and reporting. 2. Selecting the Right Azure Instance Series fortigate vm sizing azure
The "Series" you choose in Azure dictates the underlying hardware and network bandwidth.
Compute-Optimized (F-Series): High-performance instances (e.g., Standard_F2, Standard_F4) are often preferred for firewall workloads because they offer a high CPU-to-NIC ratio and strong compute power for packet inspection.
General Purpose (D-Series): These (e.g., Standard_D2s_v5, Standard_D4s_v5) are balanced options. However, be aware that throughput can vary significantly; for example, some users prefer older v2 instances over newer ones because of specific Azure bandwidth allocations.
Accelerated Networking: Crucial. Ensure your chosen VM size supports Accelerated Networking, which offloads networking tasks from the CPU to the hardware, significantly reducing latency and jitter. 3. Aligning with FortiGate Licenses
Your Azure VM resources must not exceed your Bring Your Own License (BYOL) limits, or you will waste compute power. FortiGate VM on Microsoft Azure Data Sheet - Fortinet
This guide examines the key considerations, VM series options, performance expectations, and cost trade-offs when deploying FortiGate’s Next-Generation Firewall (NGFW) as a virtual machine in Azure.
When sizing a FortiGate VM in Microsoft Azure, you must align the Azure instance type with both your expected network performance and your Fortinet licensing model. Performance & Specifications
Throughput varies significantly based on the Azure instance series and whether Accelerated Networking is enabled. FortiGate Model Azure Instance Shape vCPU (Min/Max) Azure Expected Bandwidth VM-02 VM-04 VM-08 VM-16 VM-32 16,000 Mbps Source: FortiGate VM on Azure Data Sheet Critical Sizing Factors
Memory Requirements: A minimum of 8 GB RAM is recommended for standard operation. For advanced features like Unified Threat Management (UTM) or Zero Trust Network Access (ZTNA), at least 4 GB is strictly necessary.
Network Interfaces (NICs): Sizing is often driven by the number of required interfaces rather than just CPU power. For example, the D2v2 instance type only supports 2 NICs, while D4v2 supports up to 8 NICs. Licensing Models:
Pay-As-You-Go (PAYG): The license automatically scales with the Azure instance size.
Bring Your Own License (BYOL): The license is tied to a specific number of vCPUs. While you can use a larger Azure VM, only the licensed number of cores will process traffic. Resizing Best Practices
If you need to upscale your deployment, follow these steps to prevent data loss:
Backup: Always save your FortiGate configuration before resizing.
Maintenance Window: Expect a brief period of downtime during the restart.
Process: Shut down the VM from the Azure Portal, navigate to Availability + Scale > Size, select the new instance, and power it back on.
Licensing Check: If using BYOL, ensure your new vCPU count matches your license capacity.
For detailed configuration steps, refer to the FortiOS Azure Administration Guide.
Resizing an Azure FortiGate VM instance - Fortinet Community
FortiGate VM Sizing on Microsoft Azure: Strategic Overview Selecting the correct Azure virtual machine (VM) instance for a FortiGate-VM deployment requires balancing compute power (vCPUs), memory, and—crucially for networking—the maximum number of network interface cards (NICs) supported by the Azure instance. 1. Fundamental Sizing Metrics
Azure FortiGate-VM sizing is primarily driven by three factors:
vCPU Count: Determines the parallel processing capacity for traffic and security inspection (IPS, Antivirus, Application Control).
NIC Density: Azure enforces strict limits on the number of NICs per VM size. For example, a high-availability (Active-Passive) setup typically requires at least 4 NICs (Management, Internal, External, Heartbeat), which mandates a minimum of 4 vCPUs in most Azure families (e.g., D4 series).
Throughput Requirements: Performance varies significantly based on whether security features are enabled. 2. Recommended Azure Instance Families
Fortinet generally recommends compute-optimized or general-purpose instances for production workloads. Instance type support | FortiGate Public Cloud 7.6.0
Once upon a time, in the rapidly expanding kingdom of Azure, a network architect named was tasked with deploying a FortiGate VM
to protect the realm’s digital borders. Alex knew that in the cloud, picking the wrong "armor" (VM size) could lead to either a sluggish defense or a treasury drained by overprovisioning. The Foundation: Choosing the Right Series Azure VM networking has a cumulative limit –
Alex started by looking at the standard issue Azure instance families. The Reliable D-Series : For most standard workloads, Alex looked at the Standard_D2s_v5
). These offer a solid balance of CPU and memory for everyday traffic. The Swift F-Series
: When the kingdom needed high-speed packet processing, Alex turned to the Compute-optimized F-series Standard_F2s or F8
). These were built for speed, though Alex noted they require at least 4GB of RAM to keep the defenses steady. Matching the License to the Armor
Alex discovered a curious rule in the land of FortiGate: the Azure instance must work in harmony, but they aren't identical. : If Alex bought a license, it would only use , even if he placed it on a massive 32-vCPU Azure instance. RAM Freedom
: Unlike private kingdoms (VMware), Azure doesn't strictly limit the RAM through the license, but Fortinet recommends at least 4GB to 8GB
to handle advanced features like Unified Threat Management (UTM) or SSL VPNs. The Secret Weapon: Accelerated Networking
To ensure the firewall didn't become a bottleneck, Alex made sure to enable Accelerated Networking
. This feature offloads traffic processing to the hardware, but it only works on certain Azure sizes (typically those with 2 or more vCPUs). Alex’s Quick Sizing Guide
Alex summarized his findings into a simple scroll for future architects: Recommended Azure Instance Small Branch/Dev Standard_D2s_v5 Standard Enterprise Standard_D4s_v5 High Throughput Standard_F8s If Alex ever realized the armor was too small, he could resize the VM in the Azure portal , though he always remembered that this requires a brief of the firewall. cost comparison between these common Azure instance types?
How to Change Azure VM Size — And What You Must Think About First
Mastering FortiGate VM Sizing on Azure: A Complete Guide Choosing the right size for your FortiGate VM on Microsoft Azure is a critical balancing act between security performance and cost optimization. Unlike physical appliances, virtual machines (VMs) share hardware resources, meaning your choice of Azure VM instance series directly impacts throughput, latency, and your firewall’s overall efficacy. 1. Understanding Azure VM Series for FortiGate
Azure offers several VM families, but not all are suited for high-performance security inspection.
F-Series (Compute-Optimized): Generally recommended for FortiGate because they offer a higher NIC-to-CPU ratio, which is essential for network-heavy workloads.
D-Series (General Purpose): A solid choice for standard, balanced workloads. The Dv4 and Dsv5 series are frequently used in standard FortiGate deployments.
Accelerated Networking: To avoid performance bottlenecks, ensure your chosen size supports Accelerated Networking. This offloads packet processing from the CPU to the NIC, drastically reducing latency and jitter. 2. Matching FortiGate Licenses to Azure Sizes
FortiGate VM licenses are typically tiered by the number of virtual CPUs (vCPUs) they support. Sizing your Azure instance without matching your license will lead to wasted resources. License Model vCPU Range Typical Azure Instance VM-01S Standard_D2s_v5 (throttled) VM-02S up to 2 vCPUs Standard_F2s_v2 or D2s_v5 VM-04S up to 4 vCPUs Standard_F4s_v2 or D4s_v5 VM-08S up to 8 vCPUs Standard_F8s_v2 or D8s_v5
Pro Tip: If you use Bring Your Own License (BYOL), you can upgrade from a VM-01S to a VM-02S and then resize the Azure VM to match the new vCPU count within minutes. 3. Critical Sizing Constraints
When selecting your size in the Azure Marketplace, keep these three technical limits in mind:
Network Interfaces (NICs): The number of interfaces you can attach is strictly limited by the VM size. A single FortiGate instance often requires at least four NICs (Management, External, Internal, and HA Sync).
Memory Requirements: While FortiGate-VM can run on as little as 2 GB of RAM, features like Intrusion Prevention (IPS) and Antivirus are memory-intensive. For production, aim for at least 4 GB to 8 GB to ensure the system doesn't enter conserve mode.
Throughput vs. Packet Size: Official Fortinet datasheets often list performance for large packets (1518 bytes). If your traffic is dominated by small packets (e.g., VoIP or DNS), you will need a larger VM size than the datasheet suggests to handle the higher packet-per-second (PPS) rate. 4. Deployment Strategies for Scalability
If a single VM isn't enough, consider these advanced architectures: FortiGate VM on Microsoft Azure Data Sheet - Fortinet
Sizing a FortiGate VM on Microsoft Azure requires balancing Azure's instance performance limits with Fortinet's virtual CPU (vCPU) licensing
. The primary consideration is ensuring the chosen Azure instance size provides enough vCPUs and RAM to match your FortiGate license, while also offering sufficient Network Interface Cards (NICs) for your topology. Microsoft Learn 1. Choosing Your Licensing Model
Your licensing choice directly impacts how you scale your VM in the future. Microsoft Learn
Resizing an Azure FortiGate VM instance - Fortinet Community 20 Jun 2023 — Heuristic : For full UTM (IPS + SSL
Sizing a FortiGate VM in Azure for Deep Inspection (SSL/TLS decryption) is CPU-intensive and requires careful alignment between Azure instance capabilities and Fortinet licensing. For reliable performance with deep inspection enabled, a minimum of 4 GB RAM is recommended. Core Sizing Considerations
CPU Impact: Deep packet inspection (DPI) and SSL/TLS inspection significantly increase CPU load. For example, one user's browsing and file downloading can consume up to 12% of a single CPU core when deep inspection is active.
NIC Limitations: Azure limits the number of Network Interfaces (NICs) based on the VM size. D2/D2v2: Supports only 2 NICs. D4/D4v2: Supports up to 8 NICs.
Accelerated Networking: For high-throughput requirements, ensure the chosen VM size supports Accelerated Networking (SR-IOV) to reduce CPU overhead for networking tasks. Recommended Azure Instance Types
FortiGate supports various instance families, primarily leveraging Compute Optimized (F-series) or General Purpose (D-series). Feature Need Recommended Azure Series Standard DPI D-Series (e.g., D2s_v3, D4s_v3) Good balance of compute and memory for general UTM tasks. High Performance DPI F-Series (e.g., F4s, F8s)
Higher CPU-to-memory ratio, ideal for compute-heavy SSL inspection. Scalability VMSS (Scale Sets)
Allows auto-scaling FortiGate instances based on traffic demand. Licensing vs. VM Size
It is critical to match your Fortinet license with the Azure VM's vCPU count:
FortiGate VM sizing for MS Azure - explicit proxy, full UTM, ssl deep inspeciton, ICAP
FortiGate VM Sizing in Azure: A Comprehensive Guide
As organizations increasingly move their workloads to the cloud, ensuring the security and integrity of their infrastructure becomes a top priority. FortiGate, a leading network security appliance, offers a virtual machine (VM) solution that can be deployed in Azure to provide robust security features. However, to ensure optimal performance and efficiency, it's crucial to properly size the FortiGate VM for your Azure environment. In this article, we'll delve into the key considerations and best practices for FortiGate VM sizing in Azure.
Understanding FortiGate VM
FortiGate VM is a virtualized version of the FortiGate network security appliance, which provides a comprehensive range of security features, including firewall, intrusion prevention, antivirus, and more. The VM can be deployed on various platforms, including Azure, to provide security and protection for cloud-based infrastructure.
Why Proper Sizing is Important
Proper sizing of the FortiGate VM is essential to ensure that it can handle the required network traffic and security workloads. Undersizing the VM can lead to performance issues, packet loss, and decreased security effectiveness, while oversizing can result in unnecessary costs. Therefore, it's crucial to carefully evaluate your Azure environment and security requirements to determine the optimal FortiGate VM size.
Factors to Consider for FortiGate VM Sizing in Azure
When sizing a FortiGate VM in Azure, several factors need to be taken into account:
Azure VM Instance Types for FortiGate VM
Azure offers several VM instance types that can be used for FortiGate VM deployment. Some of the most common instance types include:
FortiGate VM Sizing Guidelines
Based on the factors mentioned earlier, here are some general guidelines for sizing a FortiGate VM in Azure:
Best Practices for FortiGate VM Deployment in Azure
To ensure optimal performance and security, follow these best practices when deploying a FortiGate VM in Azure:
Conclusion
Proper sizing of a FortiGate VM in Azure is crucial to ensure optimal performance, security, and efficiency. By considering factors such as network traffic volume, security features, throughput requirements, and Azure VM instance types, you can determine the optimal FortiGate VM size for your Azure environment. By following best practices for deployment and configuration, you can ensure that your FortiGate VM provides robust security and protection for your cloud-based infrastructure.
FortiGate VM Sizing Tools and Resources
To help with FortiGate VM sizing, Fortinet provides several tools and resources:
By leveraging these tools and resources, you can ensure that your FortiGate VM is properly sized and configured to meet the security needs of your Azure environment.
Not all Azure VM sizes are equal. FortiGate is CPU-intensive (especially for VPN and SSL inspection). Memory is less critical (minimum 4-8 GB required per Fortinet, but Azure often provides more).