Manage Application Server Disks

Application server storage is provided by disks. A disk is a partition of a data store that is allocated to a specific application server. Disks can be assigned as standard or swap disks (there are no swap disks for Windows-based templates). They can also be set as primary (that is, the disk from which an OS will boot). 

You can also utilize incremental backups. For details, see Application Server Backups section of this guide.
Managing disks for the entire cloud is handled through the Control Panel's Settings menu. Disks for individual application servers are managed through the Control Panel's Application Servers menu, where you can:

Creating multiple partitions on one disk is forbidden for all application servers.


Add Disks to Application Servers



Adding a disk to an application server will require that application server should be rebooted. If an application server is running when you try to add a new disk to it, you'll be asked to confirm the reboot. To add a disk to an application server:

  1. Go to your Control Panel > Cloud > Application Servers menu.
  2. Click an application server's label to open its details screen.
  3. Click the Storage tab > Disks.
  4. Click the "+" button  or the Create Disk button.
  5. Fill in the details:

    • Specify disk label.
    • Choose the data store to create a disk on from the drop-down list.
    • Move the slider to the right to specify the desired disk size.

      Please note that support of secondary disks larger than 2 TB is limited. Certain operations might fail. This will be improved in future releases.

      • If you add a disk larger than 2 TB, you will not be able to mount or create a backup of such disk via OnApp Control Panel. These operations may be performed only manually inside a virtual server. Also, resize will not be possible for such disks.
      • You can perform the following operations with a secondary disk that is larger than 2 TB:
      • OnApp provides a RAW device available inside a VS that you may use. For example, you may create a GPT partition and format it using any available file system which can be mounted inside VS.
    • Move the Hot Attach slider to the right if you want to enable disk hot attaching. In this case application server will not be stopped when adding a disk. Prerequisite: virtual server template should support virtio virtualization and Linux OS. Hot attach option is only available for KVM 6/ CentOS 6 application servers.

    • Move the Swap Space slider to the right if this disk is swap space.
    • Move the Require Format Disk slider to the right if this disk requires formatting.

    • Move the Mounted slider to the right if the disk should be added to Linux FSTAB (for Linux application servers).

    • Specify its mount point. The maximum length of a Mount Point is 256 characters. Spaces are not allowed. No more than one slash is allowed. If the mount point is not specified the default mount point will be used:  

      /mnt/onapp-disk-#{disk.identifier}
    • Indicate the file system  - ext3 or ext4 - for Linux based application server.
  6. Click the Add Disk button to finish.

Restrictions:

  • If you choose a Solidfire data store, the minimum disk size will be regulated by Solidfire Data Store Zone settings.
  • If application server and the control panel server belong to different networks, the hot attach transaction will fail.
  • If an additional disk has been created without  therequire format disk option and formatted/partitioned in another way, resize disk action may work incorrectly. Use the require format disk option when creating an additional disk,otherwise use disk resize option at your own risk.
  • To be able to take incremental backups for application server’s disk, you must mount this disk to FSTAB (either Linux or FreeBSD) and specify the proper mount point manually.
  • You cannot back up Swap disks.
  • When you add a new disk to an application server, it automatically becomes available to that server.

Edit Application Server Disks



Primary and Swap disks

For primary and swap (Linux, FreeBSD) disks you may only change the lable and the size.
You can easily resize disks when needed. The resize will fail if your current usage is greater than the new size you request. Note, that any changes on disk size will lead to reboot of your application server.

To change disk size:

  1. Go to your Control Panel > Cloud > Application Servers menu.
  2. Make sure your application server is powered off, then click its label to open its details screen.
  3. Click the Storage tab > Disks.
  4. Click the Actions button next to the disk you want to change, then click the Edit link.
  5. Enter a new disk label and size in GB in the fields provided.
  6. Click the Save Disk button. 
  • You cannot decreasesizeof Integrated Storage datastoredisks.
  • You cannot decrease disk size for Windows-based and FreeBSD-based application servers. Only the increase disk size option is available. 
  • You cannot resize the primary disk for FreeBSD-based application servers. 
  • Decreasing disk size for Linux-based application servers may lead to filesystem inconsistencies. Make sure you have current backups before proceeding.
  • Size of a primary disk cannot exceed 2 TB.

New disks

For new disks - those which were added after the application server was created - you can edit the following:

LinuxWindowsFreeBSD
  • Label
  • Label
  • Label
  • Size
  • Size
  • Size
  • Require format 
  • Require format 
  • Require format
  • Mounted

  • Mounted
  • Mount point

  • Mount point
  • File system


Migrate Application Server Disks



You can migrate disks of your application servers to other data stores, which are allocated to the same compute resource. Unlike application server migration – disk migration requires reboot of the application server (despite the template it is based on).
To migrate a disk:

  1. Go to your Control Panel > Cloud > Application Servers menu.
  2. Make sure your application server is powered off, then click its label to open its details screen.
  3. Click the Storage tab > Disks.
  4. Click the Actions button next to the disk you want to move to another data store, then click the Migrate button.
  5. On the screen that appears, select a target data store from a drop-down box.

  6. Click Start Migrate. 

  • You can only migrate disks to data stores in data store zones assigned to your bucket. 
  • You cannot migrate a disk to a data store with less capacity than the disk size.
  • If you movea850GB disk between aggregates with 10GB actual usage, the 'dd' image of the local volume manager will take 850GB space, because the entire local volume manager is copied, includingzero 'dspace which may not be able to be recovered.

Delete Application Server Disks



To delete a disk:

  1. Go to your Control Panel > Cloud > Application Servers menu.
  2. Make sure your application server is powered off, then click its label to open its details screen.
  3. Click the Storage > Disks tab.
  4. Click the Actions button next to the disk you want to delete, then click Delete.
  5. In the pop-up window, move the Force Reboot slider to the right, then select the application server shutdown type.
  6. Move the Required Startup slider to the right to start up the application server automatically after the network is rebuilt.

    Steps 5 and 6 apply to disks of application servers that are on.

  7. Click the Destroy Disk button.