• Elastic Cloud Server

  1. Help Center
  2. Elastic Cloud Server
  3. User Guide
  4. ECS Instances
  5. Managing OSs
  6. Reinstalling the OS

Reinstalling the OS


If the OS of an ECS fails to start or requires optimization, reinstall the OS.


After the OS is reinstalled, the password for logging in to the ECS is reset. To retrieve the password, perform the following operations:


  • The EVS disk quota must be greater than 0.
  • If the target ECS is created using a private image, ensure that the private image is available.
  • H2 ECSs do not support OS reinstallation.


  • The target ECS is in the Stopped or Reinstallation failed state.
  • The target ECS has a system disk attached.
  • Necessary data has been backed up. (Reinstalling the OS clears the data in all partitions of the EVS system disk, including the system partition.)


  1. Log in to the management console.
  2. Click in the upper left corner and select the desired region and project.
  3. Under Computing, click Elastic Cloud Server.
  4. Locate the row containing the target ECS. Click More in the Operation column and select Reinstall OS.

    If the ECS is not in the Stopped or Reinstallation failed state, stop the ECS before proceeding with reinstallation.

  5. (Optional) Select a License Type (Use license from the system or Bring your own license (BYOL)) if the reinstalled OS running on your ECS is charged. For more details, see section License Type.

    The following OSs are charged:

    • SUSE Linux Enterprise Server
    • Oracle Enterprise Linux
    • Red Hat Enterprise Linux
    • Windows Server Edition OS (BYOL can be used on an ECS that is created on a DeH and runs the Windows Server Edition OS.)
  6. Configure the login mode.

    If the target ECS uses key authentication, you can replace the original key pair.

  7. Configure user data injection.
    • If you select User Data Injection and enter data in the text box, the user data imported to the ECS will be updated to the data entered in the text box.
    • If you select User Data Injection but leave the text box blank, the user data imported to the ECS will be cleared.
    • If you do not select User Data Injection, the user data imported to the ECS will not be updated.
  8. Click OK.
  9. On the ECS OS Reinstallation page, confirm the specifications and click Submit.
    After the request is submitted, the ECS status changes to Reinstalling. The reinstallation has been completed when the ECS status changes to  Running.

    A temporary ECS is created during the reinstallation process. After reinstallation, this ECS will automatically be deleted. Do not perform any operation on the temporary ECS during the reinstallation process.

Follow-up Procedure

If the reinstallation is unsuccessful, perform steps 3 to 9 again to retry reinstalling the OS again.

If the second reinstallation attempt is unsuccessful, contact customer service for manual recovery at the backend.