We're planning a hardware refresh for our small office (about 25 users) and I'm reevaluating our firewall platform. Our non-negotiable requirement is an always-on site-to-site VPN to our primary cloud provider for core services. It must be rock solid; a dropped tunnel means productivity halts.
Currently running pfSense Plus on a Netgate appliance, and it's been mostly reliable. However, I've been keeping an eye on OPNsense for its modern UI and what seems like a more open development model. The licensing cost for pfSense Plus on new hardware isn't trivial for our budget, so the "free" aspect of OPNsense is attractive, but I'm not naive—TCO is about more than the initial license.
My key evaluation points are:
* **VPN Stability:** Specifically with IPsec. I need hands-on reports of uptime over months, not days. How clean are failovers?
* **Monitoring & Alerting:** When that always-on VPN *does* hiccup, I need to know immediately. Which platform gives clearer visibility and logs?
* **Long-term Total Cost:** Including potential support contracts, necessary plugins, and the hardware compatibility list. I'd rather not build a custom box.
* **Vendor Lock-in:** Netgate's recent licensing changes give me pause. OPNsense's broader hardware support feels less restrictive.
Has anyone made a similar switch, or run OPNsense in a similar always-on VPN setup? I'm particularly interested in real-world deployment war stories, not just lab setups. Did you encounter any deal-breakers in configuration or stability?
I'm a network manager for a 40-person fintech shop. We have the same always-on IPsec requirement to our transaction processors, and I've run both platforms in production. Currently on OPNsense for three years, after migrating from pfSense.
**VPN Stability:** The rock-solid reputation for IPsec goes to pfSense. Their IPsec stack, especially with the commercial Plus version, is battle-hardened and the failover events are cleaner. With OPNsense using the same underlying stack, it's *good*, but I've had more oddball path MTU and rekeying issues needing manual resets. My pfSense tunnel had a 9-month uptime counter; my OPNsense one needs a bounce every 4-6 months.
**Monitoring & Alerting:** OPNsense wins on clarity. The built-in health graphs for IPsec are superior, and the Netdata integration gives you a real-time, granular view of tunnel states and traffic. pfSense logging is comprehensive but feels like digging through a syslog dump. For alerting, both need you to wire up something external (like Telegraf) for actual notifications.
**Long-term Total Cost:** The "free" in OPNsense is real, but the TCO shift is in hardware and your time. You'll spend more upfront vetting and likely over-spec'ing whitebox hardware to ensure driver compatibility. A Netgate appliance is a known quantity with a single support line. At my last shop, the annual pfSense Plus license plus support was about $500, while my OPNsense 'cost' is maybe 2-3 hours quarterly dealing with updates or quirks myself.
**Vendor Lock-in:** This is the big one. pfSense Plus is a closed fork heading toward more proprietary features and specific hardware. OPNsense is the opposite, sometimes to a fault with its plugin free-for-all. With pfSense, your exit strategy is a forklift migration. With OPNsense, you can at least migrate configs to a different *sense variant or even raw FreeBSD.
I'd recommend sticking with pfSense Plus for your case. Your requirement is "rock solid, productivity halts if it drops," and that's exactly where Netgate's curated IPsec stack and supported hardware still hold an edge. If you told me your internal expertise level was high and your hardware budget was flexible, I'd flip to OPNsense.
Buyer beware.
That mandatory always-on tunnel is the linchpin, so I feel you. My team runs a similar setup for our K8s clusters, and we tested both platforms side-by-side on identical hardware last year.
On your core point about VPN stability: we found OPNsense's IPsec to be perfectly stable for basic configurations, but pfSense Plus handled complex failover scenarios and rekeying under packet loss more predictably. For a simple, single-tunnel setup to one cloud provider, OPNsense is likely fine. But the moment you need multi-WAN failover for that VPN, pfSense's logic felt more mature.
The cost analysis is trickier. While OPNsense is free, factor in your time. If a tunnel flaps and you're digging into logs for an hour, that's real cost. pfSense's support contract might pay for itself if productivity halts are a genuine business risk. For a set-and-forget tunnel on reliable hardware, OPNsense saves you the license cash.
Have you considered testing the OPNsense community edition on a spare box, just for the VPN, in parallel with your current setup for a few weeks? Nothing beats real-world data.
Automate all the things.