Legacy Firewall Modernization at Scale: 55 Sites in 60 Days

Background

A regional organization operating across 55 locations had relied on an aging on-premises firewall infrastructure for years. The system had a well-documented history of limited network visibility, recurring downtime, and sensitivity to configuration changes — challenges the internal team had learned to work around rather than resolve.

The situation became critical when the organization’s data center was acquired by a larger provider. As part of the transition, the new data center assigned an entirely new IP range to the organization and came with a significantly higher monthly cost. What was already a fragile system now faced a forced, large-scale reconfiguration under a hard deadline — with no margin for extended downtime across a distributed, operational network.

The Problem

Reconfiguring 55 sites on a legacy system that was already prone to instability wasn’t just a technical challenge — it was a risk management problem. Any misconfiguration could cascade across locations, and the existing architecture offered little visibility to diagnose or contain issues quickly.

Adding complexity, the reconfiguration couldn’t stop at the firewall. On-premises facility infrastructure — including key fob access control systems and NVR security camera systems — were tied to the existing network and would need to be migrated or reconfigured alongside every firewall. The organization had roughly 60 to 75 days to complete the entire transition before the data center cutover deadline.

The legacy system simply wasn’t built to absorb a change of this magnitude gracefully. A new approach was needed.

Our Solution

NetSphere assessed the environment and recommended replacing the legacy Cisco ASA firewalls with a Cisco Meraki SD-WAN solution across all 55 locations. Rather than trying to reconfigure a brittle system under pressure, the better path was a clean migration to a modern, cloud-managed architecture that would solve the immediate deadline while also eliminating the underlying infrastructure problems for the long term.

Meraki’s centralized dashboard meant configurations could be deployed and monitored from a single pane of glass, dramatically reducing the per-site effort and risk. SD-WAN also addressed the bandwidth bottlenecks that had been a persistent issue, and the shift to a cloud-managed model reduced the organization’s dependence on the data center environment entirely — turning a forced migration into a strategic upgrade.

Results

All 55 sites were successfully migrated within the 60-day window. Beyond meeting the deadline, the project delivered improvements across the board.

During the rollout, the team discovered and developed a working integration between Keri Panel access control systems and the Meraki network infrastructure — solving a challenge that had no documented solution and ensuring facility security systems transitioned without requiring a full hardware replacement.

WiFi performance improved organization-wide as part of the upgrade. Bandwidth speeds increased by approximately 3x compared to baseline measurements on the legacy system. The network team gained significantly improved visibility across all locations, reducing the time and effort required to identify and resolve issues. What previously required on-site investigation could now be diagnosed and often resolved remotely through the Meraki dashboard.

The organization emerged from a high-pressure, externally-forced deadline with a more resilient, more capable network than it had before — and a reduced dependency on third-party data center infrastructure going forward.