Help Center> Elastic Cloud Server> User Guide (Paris Regions)> EVS Disks> Detaching an EVS Disk from a Running ECS
Updated on 2024-01-11 GMT+08:00

Detaching an EVS Disk from a Running ECS

Scenarios

You can detach EVS disks from an ECS.

  • System disks (mounted to /dev/sda or /dev/vda) can only be detached offline. They must be stopped before being detached.
  • Data disks (mounted to points other than dev/sda) can be detached online if the attached ECS is running certain OSs. You can detach these data disks without stopping the ECS.

This section describes how to detach a disk from a running ECS.

Constraints

  • The EVS disk to be detached must be mounted to a point other than /dev/sda or /dev/vda.

    EVS disks mounted to /dev/sda or /dev/vda are system disks and cannot be detached from running ECSs.

  • Before detaching an EVS disk from a running Windows ECS, make sure that UVP VMTools have been installed on the ECS and that the tools are running properly.
  • Before detaching an EVS disk from a running Windows ECS, ensure that no programs are reading data from or writing data to the disk. Otherwise, data will be lost.
  • SCSI EVS disks cannot be detached from running Windows ECSs.
  • Before detaching an EVS disk from a running Linux ECS, you must log in to the ECS and run the umount command to cancel the association between the disk and the file system. In addition, ensure that no programs are reading data from or writing data to the disk. Otherwise, detaching the disk will fail.

Notes

  • On a Windows ECS, if the disk is in non-offline state, the system forcibly detaches the EVS disk. If this occurs, the system may generate a xenvbd alarm. You can ignore this alarm.

    To view the status of an EVS disk, perform the following operations:

    1. Click Start in the task bar. In the displayed Start menu, right-click Computer and choose Manage from the shortcut menu.

      The Server Manager page is displayed.

    2. In the navigation pane on the left, choose Storage > Disk Management.

      The EVS disk list is displayed in the right pane.

    3. View the status of each EVS disk.
  • Do not detach an EVS disk from an ECS that is being started, stopped, or restarted.
  • Do not detach an EVS disk from a running ECS whose OS does not support this feature. OSs supporting EVS disk detachment from a running ECS are listed in OSs Supporting EVS Disk Detachment from a Running ECS.
  • For a running Linux ECS, the drive letter may be changed after an EVS disk is detached from it and then attached to it again. This is a normal case due to the drive letter allocation mechanism of the Linux system.
  • For a running Linux ECS, the drive letter may be changed after an EVS disk is detached from it and the ECS is restarted. This is a normal case due to the drive letter allocation mechanism of the Linux system.

OSs Supporting EVS Disk Detachment from a Running ECS

OSs supporting EVS disk detachment from a running ECS include two parts:
  • For the first part, see External Image File Formats and Supported OSs.
  • Table 1 lists the second part of supported OSs.
    Table 1 OSs supporting EVS disk detachment from a running ECS

    OS

    Version

    CentOS

    7.3 64bit

    7.2 64bit

    6.8 64bit

    6.7 64bit

    Debian

    8.6.0 64bit

    8.5.0 64bit

    Fedora

    25 64bit

    24 64bit

    SUSE

    SUSE Linux Enterprise Server 12 SP2 64bit

    SUSE Linux Enterprise Server 12 SP1 64bit

    SUSE Linux Enterprise Server 11 SP4 64bit

    SUSE Linux Enterprise Server 12 64bit

    OpenSUSE

    42.2 64bit

    42.1 64bit

    Oracle Linux Server release

    7.3 64bit

    7.2 64bit

    6.8 64bit

    6.7 64bit

    Ubuntu Server

    16.04 64bit

    14.04 64bit

    14.04.4 64bit

    Windows (SCSI EVS disks cannot be detached from a running ECS.)

    Windows Server 2008 R2 Enterprise 64bit

    Windows Server 2012 R2 Standard 64bit

    Windows Server 2016 R2 Standard 64bit

    Red Hat Linux Enterprise

    7.3 64bit

    6.8 64bit

Online detachment is not supported by the ECSs running OSs not listed in the preceding table. For such ECSs, stop the ECSs before detaching disks from them to prevent any possible problems from occurring.

Procedure

  1. On the Elastic Cloud Server page, click the name of the ECS from which the EVS disk is to be detached. The page providing details about the ECS is displayed.
  2. Click the Disks tab. Locate the row containing the EVS disk to be detached and click Detach.