You can replace the operating systems of Elastic Compute Service (ECS) instances. For example, you can replace Linux operating systems with Windows operating systems or replace Ubuntu operating systems with CentOS operating systems for ECS instances. In regions outside the Chinese mainland, versions of Linux can be replaced only with other versions of Linux and versions of Windows can be replaced only with other versions of Windows.

You can replace the operating system of an instance by replacing the system disk.

If you want to retain system disk data and reduce service downtime, use the Server Migration Center (SMC) to migrate the operating system. SMC supports the following migrations:
  • Migrate CentOS 7 to Alibaba Cloud Linux 2 or Anolis OS 7.
  • Migrate CentOS 8 to Alibaba Cloud Linux 3 or Anolis OS 8.