Attaching a Non-Shared Disk

Scenarios

You need to attach EVS disks to servers to store data. A non-shared disk can only be attached to one server. This section describes how to attach a non-shared disk to a cloud server. Disks supporting this operation include:

• Separately created data disks
• Detached data disks
• Detached system disks
  

  After a system disk is detached, the disk function changes to Bootable disk, and the status changes to Available. You can attach a bootable disk to a server to be used as a system disk or data disk depending on the disk function selected.

Prerequisites

• The account is not in arrears.
• At least one disk has been purchased or created.
• The non-shared disk status is Available. For how to check the disk status, see EVS Disk Status.
• To attach the disk as a data disk, the status of the server must be Running or Stopped.
• To attach the disk as a system disk, the status of the server must be Stopped.

Constraints

• Cloud servers created from ISO images are only used for OS installation. They have limited functions and cannot have EVS disks attached.
• A non-shared disk can only be attached to one server.
• The non-shared disk and the server must be in the same region and AZ.
• A frozen disk cannot be attached.
• A disk can only be successfully attached when its device type is supported by the desired ECS. For details, see Device Types Supported by ECS.
• To re-attach an existing disk, ensure that the following conditions are met.

  Scenario	Re-attaching Requirements
  Non-shared data disks purchased together with yearly/monthly servers	They can only be re-attached to the original servers as data disks.
  System disks purchased together with yearly/monthly servers	To re-attach and use them as system disks, you can only attach them to the original servers. To re-attach and use them as data disks, you can attach them to any desired servers.
  System disks purchased together with pay-per-use servers	To re-attach and use them as system disks, you can only attach them to servers that use the same images as the original servers. To re-attach and use them as data disks, you can attach them to any desired servers.

Attaching the Disk on the EVS Console

1. Sign in to the EVS console.
2. In the disk list, locate the disk and click Attach.
3. Select a server and then select the disk function from the drop-down list. Ensure that the disk and server are in the same AZ.

   One device name can be used for one disk only. For how to obtain the disk name in the OS, see "Elastic Cloud Server FAQs" > "How Do I Obtain My Disk Name in the ECS OS Using the Device Identifier Provided on the Console?"

   Figure 1 Attach Disk
   

4. Click OK.

   A dialog box is displayed, showing "The disk has been attached but still needs to be initialized before it can be used".

   

   If you are attaching an EVS disk with data on it, initializing the disk will erase the existing data.

5. Click OK to go back to the disk list page.

   The status of the disk is Attaching, indicating that the disk is being attached to the server. When the disk status changes to In-use, the disk is successfully attached.

Attaching the Disk on the ECS Console

1. Sign in to the ECS console.
2. In the search box above the ECS list, enter the ECS name, IP address, or ID for search.
3. Click the name of the target ECS.

   The ECS details page is displayed.

4. Click the Disks tab. Then, click Attach Disk.

   The Attach Disk dialog box is displayed.

   Figure 2 Attach Disk (KVM)
   
5. Select the target disk and specify it as the system disk or a data disk.
   • For KVM ECSs, you can specify the disk as the system disk or a data disk but cannot specify a specific device name.
   • For Xen ECSs, you can specify a specific device name, such as /dev/vdb.
   

   • For the restrictions on attaching disks, see What Are the Requirements for Attaching an EVS Disk to an ECS?
6. Click OK. A dialog box is displayed, showing "The disk has been attached but still needs to be initialized before it can be used".

   After the disk is attached, you can view information about it on the Disks tab.

Follow-Up Operations

• If you are attaching a new disk, you then need to log in to the server and initialize the disk before it can be used. To learn how to initialize disks, see Initializing EVS Data Disks.
• If you are attaching an EVS disk with data on it, you do not need to initialize it because initializing the disk will erase the existing data.

  To mount a disk partition on a specific directory of the server, run the following command on the server:

  mount <disk-partition> <mount-point>

Related Links

• If your disk cannot be attached to a server, see Why Can't I Attach My Disk to a Server?
• If the attached data disk is not showing up, see Why Can't I View the Attached Data Disk on the Server?
• If you no longer need an EVS disk or want to attach it to a different server in the same AZ, detach the disk by referring to Detaching an EVS Disk.