The recent announcement that OPNsense now provides official, maintained images for AWS EC2 and Azure Compute is a significant development for those of us operating in hybrid or cloud-first environments. While the technical convenience is immediately apparent—eliminating the manual conversion process and ensuring kernel compatibility—the more pressing question for any organization is the long-term total cost of ownership (TCO) implications beyond the simple hourly instance cost.
We must consider the architectural patterns this enables. Running OPNsense as a cloud virtual appliance typically serves a few key use cases:
* **Cloud Network Segmentation:** Acting as a firewall between VNets/VPCs or subnets.
* **Hybrid Connectivity Hub:** Terminating IPsec or WireGuard tunnels from on-premises hardware to the cloud, centralizing traffic inspection.
* **Egress Filtering & Proxy:** Controlling outbound traffic from cloud workloads, potentially integrating with services like Squid or Sensei.
The cost model therefore extends far beyond the `t3.medium` or `D2s_v3` you select. A comprehensive analysis should itemize:
**1. Compute & Licensing Costs:**
- The base instance cost (e.g., AWS `m5.xlarge` for heavier IDS/IPS).
- The OPNsense commercial edition subscription, if using the Business or Gold tiers for official support and specific features. The "free" community edition remains an option, but support is community-driven.
- Cost of increased instance sizes to accommodate throughput-intensive packages like Zenarmor (Sensei) or Suricata in inline mode.
**2. Data Transfer & Inter-Zone Traffic Costs:**
- This is often the primary cost surprise. Cloud providers charge for cross-AZ and internet egress traffic. A firewall inspecting traffic between two subnets in different Availability Zones will incur data transfer costs on both sides of the inspection.
- Example Azure pricing: Inter-VNet traffic within the same region is free, but peering across regions or to on-premises via ExpressRoute carries costs. OPNsense as a transit point makes all that traffic "billable."
**3. Associated Cloud Service Costs:**
- Managed disk storage (premium SSDs for log writing).
- Public IP address reservation.
- Potential load balancer in front for HA pairs (though OPNsense CARP itself requires multicast/broadcast, which is complex in cloud networks, often leading to active-passive setups using cloud-native failover IPs).
A preliminary, simplified cost projection for a basic AWS setup might look like this annual estimate for a single instance:
```yaml
Region: us-east-1
Instance: t3.large (2 vCPU, 8 GiB) - On-Demand
Compute: ~$0.0832/hr * 8760 hrs = ~$729
EBS Storage: 100 GB gp3 = ~$120
Data Processing: 1 TB/month outbound to internet = ~$90/month * 12 = ~$1,080
Total (approx): $1,929
```
*Note: This excludes HA, commercial license fees, and inter-AZ traffic, which could easily double this figure.*
The strategic question becomes: does running a full-featured, stateful firewall like OPNsense in the cloud provide sufficient value over native, cloud-managed services (AWS Network Firewall, Azure Firewall, or even simple NACL/Security Groups) to justify the operational overhead and potential cost multipliers? The value proposition lies in unified policy management, advanced IDS/IPS with a single rule set, and deep packet inspection capabilities that native cloud firewalls often lack or implement in a more limited, expensive manner.
I am particularly interested in community experiences with early testing of these images, specifically regarding performance benchmarking in virtualized cloud environments and any observed nuances in deploying cloud-specific configurations (like dynamic instance metadata for WAN IP). Has anyone begun to model the crossover point where a native cloud firewall becomes more economical than a sustained OPNsense deployment for a given throughput and feature set?
—A.J.
Your data is only as good as your pipeline.