Planned Disaster Recovery Sites and the Role of Firewalls

It’s me here, Pen unfolded in all my glory with my third coffee of the morning and I’m pondering disaster recovery (DR) sites… and actually the humble firewall at the DR end, all that get-configuring-ready-to-receive-firewall-traffic-gubbins and, you know, getting the firewall all primed and ready for our regular, all-important DR drills and failovers. A few times around the block since I started as a network admin in ’93. Witnessed voice and data multiplexing over PSTN as it emerged, lived through the chaos of the Slammer worm firsthand (yes, the one that clogged the internet), and here I am, running my own security firm, helping banks upgrade their zero-trust architectures just last quarter. So here’s the deal—why the firewall rental for your DR site is making my life—and maybe yours—much easier.

DR Architecture Needs

Disaster recovery is not just a checkbox for compliance. That’s what it’s about: making sure your network can breathe and continue when the unthinkable happens. From the years I spent bouncing between cables and configs in the early days, or on the most recent ZT projects, DR is always about hard decisions about hardware:

Would you purchase a $1,200 firewall to sit dormant 99% of the time?
— Or do you patch together equipment that you already own and hope works when it’s needed?

Your DR site firewall must be a replica of your production posture so the bad guys can’t side-step your DR site and make a mess on the other side. Otherwise it’s all that failover work for nothing. It’s like any other vintage car — you don’t show up to the race in the old family sedan.

And here’s a (frustrating) point that’s true: DR isn’t a one-time setup. It needs frequent testing. Regular drills expose the gaps, while also racking up costs. Having dedicated firewalls at the DR site is capital tied up—and hardware that aged not in use.

Rental Deployment in DR

This is also where renting firewalls for your DR site restructuring comes into play. I’ve helped several banks switch to firewall rentals in the last couple of years and frankly, I’m a fan. It’s simple:

• Rent the specific firewalls that you use in your production network.
• Pre-configure them with your security policies beforehand the drill.
• Only deploy it for failover events or for testing!

No more buying external gear that just sits in a corner, gathering dust. The rental services would take care of maintenance and updates — your team could focus on actual drill readiness. By the way, it also reduces the risk of firmware drift – that curse of DR exercises when the DR firewall is a rev behind your live site.

Plus, it’s flexible. Your DR footprint can expand and contract without painful hardware purchases. I know this from experience. One of my first clients purchased DR firewalls in a big bang—was running on two-year-old obsolete gear. Renting will help you stay current and remain auditable.

Test & Failover Procedures

Testing DR failover has always been the equivalent of getting ready for the garage race—lots of tuning, last-minute fixes and hope the old beast makes it around the track. But it’s easier with rented firewalls:

• Firewalls arrive preloaded.
• You do have you regularly scheduled drills.
• Changes and patches are more comfotable to deploy in centrule maneged rented units.

Lesson learnt here is don’t wait until things go wrong before you test and make sure your DR firewall is working. Aggressive drills find the latent issues — from what I’ve seen, even mature organizations overlook subtle config mismatches when it only happens once a year.

Here’s a tip you should feel free to run with: if you rent firewall rental as well in order to do scenario-specific drills where you take it in turns to simulate a WAN drop, a DDoS, firmware faults etc. It’s more efficient, more cost efficient, and you’re getting in-the-moment feedback.

But — and this is a big but — don’t discount the human factor. DR drills fall over when operations aren’t trained or the scripts they use are out of date. Renting doesn’t fix that. You want to keep your people sharp. The firewall is only one part of the orchestra.

Cost per Drill

Now, let’s talk money. The counterargument to rentals is typically that “buying is cheaper in the long run.” Only when you consider hardware use, not idle time. What’s the expense of your firewalls remaining unplugged for 11 months of the year?

Cost factors to consider:

• Rental rates based on real use.
• Maintenance and support included (no unexpected charge for firmware updates).
• No capital expenditure (CAPEX) impact up front, only operational expense (OPEX).
• Can replace models if you later party in production.

Numbers, too, were something I crunched for one client, a mid-size bank. They put aside almost 40% a year by renting alone. That’s money coming back into cybersecurity projects, not chilling in old storage gear.

Remember, DR is not just about having gear; it’s also about agility. Renting enables you to evolve budget and tech alongside threats — rather than being locked into a firewall that’s obsolete before you’ve even reached your next drill.

Post-DR Evaluation

Regarding the step of evaluating, after every single DR drill (be it with rented firewalls or owned gear) I would always emphasize this point. Here is where true learning takes place:

• Look at firewall logs and the firewall configurations after failover.
• Confirm that security policy was maintained under load.
• Ensure monitoring and alerting are functional.

Interview teams about what was easy, what was not and what you did not expect.

One recent example: a firewall rented to use for a simulated outage turned up an internal misconfiguration – something the production site’s own firewall missed. Twice. We patched it immediately. It is this kind of understanding that I don’t it’s worth it in the end to go through the DR drills.

And the kicker is that leasing firewalls makes post-drill tweaks less painful. And since it isn’t a hardware capoxexse, you can do slight utilization games or change up your DR configs or firewall model with less “bureacracy”.

Quick Take

For those of you who are skimming because time for reading is but one of a dozen competing priorities:

• Renting firewalls = flexible and cheaper than purchasing stand-by DR hardware.
• DR drills cause less pain and are therefore run more often — which leads to better real readiness.
• Post-drill learnings get adopted more rapidly when you’re not yoked to obsolete gear.
• Training and documentation still needed — “You can’t rent your way out of bad processes.”

Final Thoughts

Look, I’m old enough to have seen the good, the bad and the ugly with network security — from coax and mux configurations all the way to the new zero-trust architectures still trying to figure themselves out. What I have come to realize is DR is a moving target. The firewall is an important piece, sure — but it’s the process that matters most.

Renting firewalls just seems like the way of modern to keep your DR site honest and ready without a maybe, maybe not big chunk of cabinets and capital expense. Some people argue that rentals add complexity or hidden costs — I understand the cynicism (I’m also the guy who remains uneasy about AI-powered security devices). But, after spending time in a few banks and at some high-pressure firms, this model just feels right.

And on a personal note — after my recent DefCon wander through the hardware hacking village, I’m reminded that security isn’t just about software policies or AI hype. It’s the nuts and bolts — the real, tangible testable kits we bring to the table during real disaster moments. Being able to rent firewalls means that kit’s in your hand precisely when you want it.

So yeah, consider it. It’s not just convenience. It’s preparedness.

I swear, where did that fourth cup of coffee go?