Major incident

Anaplan: Platform Alerts

Affected: us1: Data Center - US East, us2: Data Center - US West, eu1: Data Center - Netherlands, eu2: Data Center - Germany, eu4: Cloud - Europe, us5: Cloud - US East, ap1: Cloud - Japan, us7: Cloud - US

Current status of Anaplan: Operational — live Anaplan status

Timeline

1. Jun 8, 2026, 11:10 UTC
   investigating
   We are currently investigating an issue impacting customers’ ability to access the Anaplan Platform. We are working to resolve this issue as quickly as possible and will provide updates every 30 minutes or upon resolution.
2. Jun 8, 2026, 11:28 UTC
   monitoring
   We are currently investigating an active incident that may affect Basic Authentication access. Recommended workaround while we resolve the issue: - Close your current session— Close the active browser tab or open a new Incognito/Private window. - Re-authenticate— Navigate to the portal and log in again with your credentials to establish a fresh session. We are actively monitoring the platform and will continue to do so until the issue is fully resolved. If you are still experiencing difficulties or have any questions, please reach out to Anaplan Support We will provide a final update to you when we consider this situation fully resolved
3. Jun 8, 2026, 12:41 UTC
   resolved
   We have confirmed that the issue is now resolved. We deeply apologize for any impact this issue may have caused. We appreciate your patience and partnership as we worked through this issue. We will follow up within 7 business days with a detailed root cause analysis (RCA) that will be shared on our Status Page. If you have any question or concerns, please do not hesitate to contact us at Anaplan Support.
4. Jun 19, 2026, 14:25 UTC
   postmortem
   **June 8–12, 2026 Platform Disruptions** On June 8, 2026, at 11:05 UTC, our monitoring detected a brief drop in incoming traffic across the Anaplan platform, with automated monitoring checks failing across all affected regions \(us1: Data Center - US East, us2: Data Center - US West, eu1: Data Center - Netherlands, eu2: Data Center - Germany, eu4: Cloud - Europe, us5: Cloud - US East, us7: Cloud - US, and ap1: Cloud - Japan\). Over the four days, a series of related disruptions affected the same regions. Customers experienced intermittent difficulties logging in, opening models, and running integrations. The platform was fully stabilized on June 11, 2026, at 18:12 UTC. These disruptions are linked to our previously communicated infrastructure modernization program. On the weekend of June 6, we migrated our control plane, the part of the platform that directs how traffic is routed between services. This was the most complex of the planned migration weekends, and it was completed successfully, as had the two previous migration weekends. The issues described in this report emerged in the days following that migration. This report covers the seven linked incidents that occurred between June 8 and June 11, 2026. **Root cause** As part of our infrastructure modernization program, on the weekend of June 6, we completed a successful migration of our control plane. In the days that followed, we observed two discrete network-hardware issues that interacted to drive these disruptions. _Issue 1: Media Access Control \(MAC\) flapping \(June 8–9\)_ Every device on a network has a MAC address, a unique hardware identifier that network switches use to route traffic to the correct destination. In our environment, the MAC addresses involved are virtual — assigned to logical network gateways rather than to fixed physical hardware — which allows them to legitimately move between hosts as part of normal operation. MAC flapping occurs when a switch sees the same MAC address appearing on two different physical ports in rapid succession, forcing it repeatedly to update its routing tables. This briefly slows or interrupts traffic. For customers, this surfaced as a brief, self-recovering instability. Short bursts of load and intermittent errors appeared and cleared on their own within minutes. The trigger for this behavior was the specific way live production traffic interacted with the new post-migration network. To resolve the issue, we scaled capacity, engaged our vendor, and deployed configuration changes to contain the impact. _Issue 2: network card driver defect \(June 10–11\)_ Once the first set of mitigations were in place, we identified a second issue: A defect in the network card driver, which is the software that controls how a network card sends and receives data. The defect affected fewer than 0.005% of the cards in our estate. Those cards failed randomly and unpredictably, dropping traffic while still appearing healthy to our monitoring systems. This is known as a "gray failure" condition, because the affected components don’t flag themselves as broken. The cards sat in the part of the network that routes traffic between the regions impacted. This resulted in failures that cascaded across the platform and drove disruptions on June 10 and June 11. The defect hadn't been observed in previous migrations or in any other environment, and there were no indicators in pre-deployment testing. The gray failure pattern was also what initially masked the defect as a load issue, until further investigation pointed us to the driver itself. We engaged our vendor, who confirmed the defect. Working closely with them, we rapidly prepared, tested, and deployed the patch to the affected hosts on the evening of June 11, UTC. After that, the platform stabilized. **Recovery** From the first occurrence on June 8 through to permanent resolution on June 11, our engineering team led a continuous, round-the-clock response, working closely w

Updates as published by Anaplan (original).