Citrix Systems 4.2 manual Working With Volumes, Changing Secondary Storage Servers

Chapter 14. Working With Storage

Then log in to the CloudPlatform UI and stop and start (not reboot) the Secondary Storage VM for that Zone.

14.3.3. Changing Secondary Storage Servers

You can change the secondary storage NFS mount. Perform the following steps to do so:

1.Stop all running Management Servers.

2.Wait 30 minutes. This allows any writes to secondary storage to complete.

3.Copy all files from the old secondary storage mount to the new.

4.Change the IP address for secondary storage if required. See Section 14.3.2, “Changing the Secondary Storage IP Address”.

5.Start the Management Server.

14.4. Working With Volumes

A volume provides storage to a guest VM. The volume can provide for a root disk or an additional data disk. CloudPlatform supports additional volumes for guest VMs.

Volumes are created for a specific hypervisor type. A volume that has been attached to guest using one hypervisor type (e.g, XenServer) may not be attached to a guest that is using another hypervisor type (e.g. vSphere, Oracle VM, KVM). This is because the different hypervisors use different disk image formats.

CloudPlatform defines a volume as a unit of storage available to a guest VM. Volumes are either root disks or data disks. The root disk has “/” in the file system and is usually the boot device. Data disks provide for additional storage (e.g. As “/opt” or “D:”). Every guest VM has a root disk, and VMs can also optionally have a data disk. End users can mount multiple data disks to guest VMs. Users choose data disks from the disk offerings created by administrators. The user can create a template from a volume as well; this is the standard procedure for private template creation. Volumes are hypervisor- specific: a volume from one hypervisor type may not be used on a guest of another hypervisor type.

Note

CloudPlatform supports attaching up to 13 data disks to a VM on XenServer hypervisor versions 6.0 and above. For the VMs on other hypervisor types, the data disk limit is 6.

14.4.1. Creating a New Volume

You can add more data disk volumes to a guest VM at any time, up to the limits of your storage capacity. Both CloudPlatform administrators and users can add volumes to VM instances. When you create a new volume, it is stored as an entity in CloudPlatform, but the actual storage resources are not allocated on the physical storage device until you attach the volume. This optimization allows the CloudPlatform to provision the volume nearest to the guest that will use it when the first attachment is made.

14.4.1.1. Using Local Storage for Data Volumes

You can create data volumes on local storage (supported with XenServer, KVM, and VMware). The data volume is placed on the same host as the VM instance that is attached to the data volume. These

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