Table of Contents
- Are You Ready for the Critical Microsoft SharePoint Online CDN Migration? Avoid Negative Surprises in 2025
- Key Details of the Migration
- Timeline
- New CDN Domain
- No Immediate Admin Action Required
- Allowlist Update
- Avoid Hardcoding URLs
- Announcement Reference
- Why This Migration Matters
- What Should Administrators Do?
- Review Network Allowlist Settings
- Check for Hardcoded CDN URLs
- Monitor Updates
- No Immediate Changes Needed
Microsoft is making a significant change to SharePoint Online, beginning June 2025, by migrating its content delivery infrastructure to a new CDN (Content Delivery Network) service-Microsoft Azure Front Door (AFD). This transition is designed to enhance the performance, reliability, and scalability of SharePoint Online for organizations worldwide.
Key Details of the Migration
Timeline
The migration will start in early June 2025 and is expected to be completed by late July 2025.
New CDN Domain
SharePoint Online assets will now be delivered through a new public CDN domain:
public-cdn.sharepointonline.com.
No Immediate Admin Action Required
Microsoft has confirmed that no administrative measures are needed before the rollout. The migration will be handled automatically.
Allowlist Update
- Organizations using domain-based allowlists in their network configurations must ensure that public-cdn.sharepointonline.com is included.
- Continue to allow the old CDN domain until Microsoft officially retires it, to prevent service disruptions.
Avoid Hardcoding URLs
Do not hardcode CDN URLs in your configurations. This ensures flexibility and seamless updates during and after the migration.
Announcement Reference
This update was first announced in the Microsoft 365 Message Center under ID MC1066155.
Why This Migration Matters
- Performance Boost: Leveraging Microsoft Azure Front Door will improve the speed and reliability of content delivery for SharePoint Online users globally.
- Future-Proofing: The new CDN infrastructure is designed to support evolving organizational needs and future Microsoft 365 enhancements.
- Security and Compliance: Updating allowlists and avoiding hardcoded URLs help maintain a secure and compliant environment during the transition.
What Should Administrators Do?
Review Network Allowlist Settings
Add public-cdn.sharepointonline.com to your allowlist if you restrict domains for outbound traffic.
Check for Hardcoded CDN URLs
Update scripts or configurations to avoid referencing old CDN URLs directly.
Monitor Updates
Stay informed about further communications from Microsoft regarding the official retirement of the old CDN domain.
No Immediate Changes Needed
The migration is automatic; no manual intervention is required before June 2025.
This migration is a proactive move by Microsoft to deliver a faster, more reliable, and secure SharePoint Online experience. By preparing your network settings and avoiding hardcoded URLs, your organization can benefit from these improvements without disruption. If you have questions or need support, Microsoft recommends reaching out to their support team for additional guidance.