Cisco & Meraki specialists. Across the UK.
+44 203 196 6566 · option 1sales@proxar.co.uk

Connect. Secure. Manage.

Cisco ASA Migration

Plan a migration from Cisco ASA to Secure Firewall, reviewing rule conversion, NAT, VPN dependencies and differences that require redesign.

Cisco Partner since 2009 Projects & ongoing support

Illustrative Cisco and Meraki network operations centre with monitoring displays
Your network. Properly considered.Design · Implementation · Support
1,000+

Devices supported
across the UK

20+

Client locations
supported

Nearly 8 Tbps

Traffic handled
at peak time

3 min

Average
response time

Average response is not a resolution time or a contractual guarantee. Support scope and response commitments are agreed for each engagement.

Cisco ASA migration is a policy and service transition, not merely a hardware replacement. Existing ASA configurations can contain years of NAT rules, VPN dependencies, object groups and exceptions that need interpretation before they move. MCI Network Services assesses the current service, designs the supported target and carries out a staged migration with application testing and a practical recovery plan.

01

Defined trust

Make access boundaries explicit rather than relying on an assumed internal network.

02

Controlled access

Connect identity, policy and network enforcement to the services people actually use.

03

Evidence for change

Test the intended security outcome and retain useful operational records.

Establish what the ASA is doing today

We inventory interfaces, routing, address translation, access rules, remote-access and site-to-site VPNs, administrative controls and any special operating mode. The customer identifies the applications and external organisations that depend on the device. A configuration export is the starting point, not a complete explanation of the service.

We also review usage and ownership. Some rules may be unused, while others support occasional processes that will not appear in a short observation period. We distinguish candidates for removal from confirmed obsolete entries. The customer approves any reduction in access so that a migration does not unintentionally become an undocumented security-policy redesign.

Illustrative Cisco and Meraki data-centre network infrastructure
01Network infrastructure designed around the workloads it carries.
Cisco PartnerCisco Partner
Cisco MerakiCisco Meraki
ISO 9001Quality management
ISO 27001Information security
Cyber EssentialsCyber Essentials
Cyber Essentials PlusCyber Essentials Plus

MCI Network Services is operated by Proxar Ltd. Certifications apply to the certified legal entity and the scope of its certificates. View accreditation information

Choose a target that supports the requirements

The proposed Cisco platform and management model are checked against the functions actually required. Feature equivalence is not assumed. A supported migration utility may help translate configuration, but it does not guarantee that every feature, policy interaction or operational workflow transfers unchanged.

We identify differences that need a design decision, including NAT behaviour, inspection, VPN authentication, interface layout and logging. Licensing and software compatibility are reviewed before the target is procured or staged. The customer receives a gap register explaining what will be preserved, what changes and which requirements need another solution.

Illustrative Cisco and Meraki fibre network rack with structured cabling
02Fibre, switching and the physical path behind the service.

A useful starting point

Not sure where to start?

Bring the requirement. We will help you define the engineering work.

Talk to a specialist

Translate policy with context

Objects and rules are mapped to the intended traffic path rather than copied without review. We examine which addresses a rule matches before and after translation and how return traffic reaches the correct stateful device. A syntactically valid conversion can still produce a different result when NAT order or routing assumptions change.

We also review broad exceptions introduced during past incidents. Where the customer authorises cleanup, those changes are separated and tested. Combining too many unrelated policy changes with a platform cutover makes fault isolation harder. The migration plan identifies the minimum changes needed for the target and any improvements deliberately deferred until the new service is stable.

Illustrative enterprise Cisco network rack in a modern office environment
03Enterprise switching and routing, built to be operated.

Prepare VPN and identity dependencies

Remote-access clients, certificates, authentication services and partner VPN peers can require coordinated changes. We identify their owners and agree how each connection will be validated. A firewall migration can appear successful for ordinary internet traffic while a rarely used partner tunnel or remote-user group remains broken.

Certificates and secrets are handled through approved secure channels. We plan any change in public addresses, DNS names or trust chains before the window. Client software and profile compatibility are checked separately from the firewall configuration so that users are not asked to solve an endpoint migration during the network cutover.

Illustrative Cisco and Meraki equipment in a modern data-centre aisle
04Resilient infrastructure from rack to service path.

Stage the new service and rollback

We prepare the target configuration, compare it with the approved mapping and exercise representative traffic where a test environment is available. Physical interfaces, cabling and management access are documented. The staging record identifies what has been tested and what can only be validated against the live external service.

Rollback includes the old device, cabling, routing and any provider-side changes. We define a decision point and the time needed to return to the previous state. Some sessions will need to reconnect even when the network path is restored, so application owners are involved in the recovery plan rather than expecting a configuration backup to solve every consequence.

Illustrative Cisco and Meraki equipment in organised data-centre racks
05Data-centre connectivity with clear physical and logical boundaries.

Cut over with a defined acceptance matrix

The change sequence separates basic forwarding, application access, VPNs and inspection checks. Engineers verify the expected translations and return paths before declaring a service restored. Denied traffic is tested as well as permitted traffic so that the migration does not obtain apparent success by broadening access.

For resilient designs, we exercise agreed failover scenarios and observe the effect on representative sessions. Any test that cannot safely be performed is recorded as unverified. The final acceptance is based on evidence from the actual service, not solely on the migration tool's completion report.

The observation period also checks less frequent workflows identified during discovery, such as scheduled transfers and supplier maintenance. Where those cannot run during the cutover window, they receive a named follow-up test and owner. A successful first morning of browsing is not a reason to discard the recovery plan prematurely.

Illustrative Cisco and Meraki network operations centre with monitoring displays
06Visibility, monitoring and operational control.

Retire legacy access and records safely

After the agreed observation period, we remove obsolete credentials, management allowances and unused equipment through the customer's process. Required configuration and audit records are retained appropriately. MCI can then support the target through Cisco Secure Firewall services, with the new policy ownership, software lifecycle and escalation responsibilities made clear in the handover.

Illustrative Cisco and Meraki data-centre network infrastructure
07Network infrastructure designed around the workloads it carries.

Technical references

Illustrative Cisco and Meraki fibre network rack with structured cabling
08Fibre, switching and the physical path behind the service.

Talk to a specialist

What does your network need next?

Tell us what you are planning, changing or trying to improve. We will help define a practical next step and the engineering scope.

+44 203 196 6566

Choose option 1

sales@proxar.co.uk

UK-wide service.
Most of our engineers are based in Kent, with a focus on London, Sussex, Essex and Berkshire.

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