Dear Alibaba Cloud customers, to continuously improve the security of our cloud network environment, we are planning to implement security hardening for access policies of Elastic IP Addresses (EIPs) in cut-through mode. Starting from April 23, 2026, 00:00 (UTC+8), EIPs with the association mode set to Cut-through Mode will no longer be allowed to access the Alibaba Cloud reserved CIDR block 100.64.0.0/10. If you are currently using EIPs with the association mode set to Cut-through Mode to access cloud services within the 100.64.0.0/10 CIDR block, you will not be able to continue accessing them after April 23, 2026. To ensure smooth business operations, please configure the route for 100.64.0.0/10 to point to the primary elastic network interface (ENI) of your ECS instance before April 23, 2026.

For detailed instructions, please refer to the product announcement. Thank you for your understanding and cooperation. We will continue to enhance our product security capabilities to provide you with a more reliable cloud service experience. If you have any questions, please contact us through your account manager.

To ensure smooth business operations, please configure the route for 100.64.0.0/10 to point to the primary elastic network interface (ENI) of your ECS instance before April 23, 2026.For detailed instructions, please refer to the product announcement.