API & Integrations - Enhancing API Gateway Resilience - Jun 2025

Service Update

Availability	June 3rd, 2025
Product(s)	API & Integrations
Who's affected	All API customers

Overview

Mimecast is pleased to announce that we are enhancing the resilience and availability of our API services by introducing a new API Gateway instance in the United Kingdom. This additional gateway will complement our existing API Gateway in the United States, improving load distribution, reducing latency for UK and EU users, and ensuring seamless service availability during regional disruptions.

What's changing

• Improved Performance: API customers in the UK and surrounding regions will benefit from reduced latency and enhanced performance.
• Increased Redundancy: Failover capabilities are being added to further strengthen service availability.

API Gateway Options

We now offer three API gateway options to meet your performance, compliance, and data residency needs:

Factor	Global URL	UK Instance URL	US Instance URL
URL Details	http://api.services.mimecast.com/	http://uk-api.services.mimecast.com/	http://us-api.services.mimecast.com/
Availability	Auto failover for high uptime	No failover - requests fail if UK instance is down	No failover -requests fail if US instance is down
Compliance & Data Residency	May process data in other regions during failover	Ensures data stays within the UK instance	Ensures data stays within the US instance
Customer Effort	No action required	Existing integrations need updating with the regional URL	Existing integrations need updating with the regional URL
Failover Customer Effort	No action required (automatic failover for downtime)	Manual configuration needed for failover	Manual configuration needed for failover
Risk of Downtime	Minimal risk (automatic failover)	Higher risk if no backup region is configured	Higher risk if no backup region is configured

Key Details

• Global URL: The existing global API URL (api.services.mimecast.com) will continue to serve customers as it does today. No changes are required for customers using this URL, as all integrations will work seamlessly.
• UK Instance URL: For compliance and data residency requirements, customers can choose to process traffic via the UK instance using the regional URL (uk-api.services.mimecast.com.) This ensures API traffic is only processed within the UK instance of the Apigee Gateway.
• US Instance URL: Similarly, customers with compliance or residency requirements in the US can use us-api.services.mimecast.com to process API traffic exclusively through the US instance of the Apigee Gateway.

Important Notes

• This update applies only to Mimecast API 2.0 publicly available APIs.
• Current Mimecast-managed API integrations and Mimecast User Interfaces will continue to use the global APIs to call the Mimecast API Gateway.
• It does not apply to API 1.0 endpoints, as traffic for API 1.0 does not process through the Apigee Gateway.
• For third-party managed API integrations using API 2.0, customers may choose to update the URL with regional endpoints if the external organization supports providing Mimecast hostnames.

Recommended actions

No action is required as a result of this enhancement. This change will not impact your current integrations or configurations, unless you choose to use the regional instance URLs for compliance or residency requirements.

We remain committed to improving the resilience, performance, and reliability of our platform. If you have any questions or require assistance, please reach out to your Mimecast representative.