By Massive IT · October 12, 2026
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Documented engineering milestones
Recorded milestones from this engagement, not SLA commitments.
~50 min
Ticket creation to working session
77 min
Initial engineering session
3 routers
VXLAN EVPN configured
Engagement timeline
Day 1
Emergency escalation, routing-loop diagnosis and coordinated stabilization.
Days 6–7
Maintenance window, static-route cleanup, OSPF /32 corrections and EVPN/VRF deployment.
Week 2
Test-host Internet access, inconsistent application performance and a leaked default-route correction.
Weeks 2–3
MTU hypothesis, traffic-symmetry analysis, vendor consultation and planned validation.
Routing architecture: before and after
Before · Legacy routing dependencies
Solid: routed links. Amber: stale-route forwarding loop.
After · Modernized control plane
Solid: underlay links. Dashed blue: overlay/control-plane exchange. Data-plane validation outstanding.
Executive summary
A regional broadband provider encountered a routing disruption that exposed legacy static-route dependencies. Massive IT partnered with its internal network team to diagnose the issue, implement routing corrections, and modernize its network using BGP EVPN and VXLAN.
Engineers isolated the interaction between stale static routing and OSPF advertisements and supported a risk-aware stabilization strategy. The engagement expanded into OSPF cleanup, BGP routing adjustments, and a VXLAN EVPN overlay across multiple core routers. At the final documented update, routing changes and the EVPN control plane were implemented, while traffic-performance anomalies and MTU validation remained open.
Customer environment and challenge
The provider operated a multi-site routed core with upstream Internet connectivity and a mixture of OSPF, BGP, and historical static routes. A failed inter-site path forced traffic onto alternate routes. A stale route to a remote loopback directed traffic toward a device that forwarded it back, producing a loop. An OSPF advertisement used a broader-than-intended loopback mask, further complicating reachability.
The customer needed immediate assistance without introducing additional risk during a separate upstream-carrier issue.
Phase 1 | Incident response and stabilization
The support request was logged at 3:42 p.m. Eastern. Massive IT’s engineering working session began at 4:32 p.m., approximately 50 minutes later, and lasted 77 minutes. These are documented engineering milestones, not SLA commitments.
Working collaboratively, engineers traced the alternate default path, identified the stale static route and incorrect loopback advertisement, and evaluated corrective changes. Disruptive corrections were deferred to a coordinated maintenance window while temporary connectivity was maintained.
Phase 2 | Routing corrections and VXLAN EVPN modernization
During scheduled overnight maintenance, unnecessary static routes were removed and OSPF network statements and loopback advertisements were corrected to host-specific /32s. Engineers configured VXLAN EVPN on three core routers, including a Layer 2 VNI, distributed anycast gateway, and VRF-based Layer 3 routing.
BGP advertisements and route leaking between the global table and service VRF were adjusted for upstream reachability. Recorded post-change checks confirmed VXLAN tunnel establishment, EVPN route exchange, and MAC/ARP learning. End-to-end application performance had not yet been fully validated.
Phase 3 | Performance investigation and follow-through
A test host achieved Internet access through the new service VRF, but some webpages stalled, throughput was inconsistent, and certain large transfers degraded while other applications functioned normally. A missing leaked default route on one core router was identified and added.
Massive IT identified a plausible MTU issue on core-facing links carrying VXLAN encapsulation and recommended validating larger frames and adjusting MTU consistently on both ends of relevant links. Engineers also noted equal-cost VRF defaults toward two upstream providers that could bypass normal BGP preference and introduce traffic asymmetry. These remained hypotheses or recommendations until further testing, not confirmed fixes.
Business and technical outcomes
The engagement combined specialist escalation, disciplined change management, and ongoing collaboration with the customer’s internal engineering team. Confirmed outcomes included diagnosis of a legacy routing loop, removal of unneeded static routes, correction of OSPF loopback advertisements, implemented VXLAN EVPN configuration, established overlay control-plane exchange, and a targeted VRF default-route correction.
The work created a clearer architectural foundation for future service delivery. No numerical uptime improvement, validated throughput gain, or completed end-to-end failover result is claimed.
Final documented status
Operational network with outstanding traffic-performance issues.
| Completed and confirmed | Outstanding validation |
|---|---|
| Routing diagnosis and static-route cleanup | Coordinated MTU review with the equipment vendor |
| OSPF corrections and BGP/VRF adjustments | Large-packet and application testing |
| VXLAN EVPN configuration and control-plane validation | Upstream default-route preference and traffic-symmetry review |
| Missing leaked VRF default route corrected | End-to-end data-plane performance confirmation |
Massive IT continued providing engineering guidance alongside the customer’s team.
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Engineering detail
Root cause and static-route loop
Confirmed: a stale static route sent traffic toward a device that forwarded it back. An alternate path exposed this legacy dependency; disruptive changes were coordinated for maintenance.
OSPF /32 changes
Confirmed: unnecessary static routes were removed, and OSPF network statements and loopback advertisements were corrected to host-specific /32s.
BGP EVPN and VXLAN overlay
Confirmed: VXLAN EVPN was configured on three core routers with a Layer 2 VNI, distributed anycast gateway and VRF-based Layer 3 routing. Tunnel establishment, route exchange and MAC/ARP learning were checked, not complete application performance.
VRF route leaking and default routes
Confirmed: global-table/service-VRF route handling was adjusted and a missing leaked default route was added. Equal-cost upstream VRF defaults remained a traffic-asymmetry hypothesis requiring review.
MTU overhead and outstanding performance validation
Recommendation, not a completed fix: validate larger frames and consistent MTU on both ends of VXLAN-carrying core links with the equipment vendor. Large-packet, application and end-to-end data-plane testing remained open.