then the plug-in will use all of the space on the SAN for creating VDIs. When the SR is created, a small amount of meta data is created, called the SR Management Volume. This will be displayed as the smallest volume (30MB). All of the VDIs in the SR are created with 100% space reserved for snapshots by default. This will also override the Group Defaults that are set by the administrator from the EqualLogic GUI/CLI. You can change this default by using a sm-configparameter while creating a VDI via the xe CLI.

Creating a VDI using the CLI

To create a VDI using CLI use the xe vdi-create command:

xe vdi-create virtual-size=10GiB name-label=testvdi \ sr-uuid=<sr_uuid>>type=user sm-config:allocation=<thin thick> \ sm-config:snap-reserve-percentage=<Percentage Integral Value> \

sm-config:snap-depletion=<delete-oldest volume-offline>

Where <sr_uuid> is the UUID of the SR of type Dell EqualLogic.

sm-config:allocationcontrols whether the VDI volume is provisioned as a thin volume or not. Setting sm-config:allocation=thinwill create a volume with thin provisioning enabled. Setting sm- config:allocation=thick will create a volume with thick provisioning disabled. If the type of allocation is not specified, the default allocation for the SR is used to provision the VDI volume.

sm-config:snap-reserve-percentagespecifies the amount of space, in terms of percentage of volume, to reserve for volume snapshots.

sm-config:snap-depletionspecifies the snapshot space recovery policy action taken when the space reserved for snapshots has been exceeded. Setting sm-config:snap-depletion=delete-oldestdeletes the oldest snapshots until sufficient space is recovered (the default).

Setting sm-config:snap-depletion=volume-offlinesets the volume and snapshots offline. Active iSCSI connections will be terminated before a snapshot is automatically deleted.

NetApp

The NetApp type maps LUNs to VDIs on a NetApp server, enabling the use of fast snapshot and clone features on the filer.

Note:

NetApp and EqualLogic SRs require XenServer Advanced edition or above to use the special integration with the NetApp and Dell EqualLogic SR types, but you can use them as ordinary iSCSI, FC, or NFS storage with free XenServer, without the benefits of direct control of hardware features. To find out about XenServer editions and how to upgrade, visit the Citrix website here.

If you have access to Network Applianceā„¢ (NetApp) storage with sufficient disk space, running a version of Data ONTAP 7G (version 7.0 or greater), you can configure a custom NetApp storage repository for VM storage on your XenServer deployment. The XenServer driver uses the ZAPI interface to the storage to create a group of FlexVols that correspond to an SR. VDIs are created as virtual LUNs on the storage, and attached to XenServer hosts using an iSCSI data path. There is a direct mapping between a VDI and a raw LUN that does not require any additional volume metadata. The NetApp SR is a managed volume and the VDIs are the LUNs within the volume. VM cloning uses the snapshotting and cloning capabilities of the storage for data efficiency and performance and to ensure compatibility with existing ONTAP management tools.

As with the iSCSI-based SR type, the NetApp driver also uses the built-in software initiator and its assigned host IQN, which can be modified by changing the value shown on the General tab when the storage repository is selected in XenCenter.

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Citrix Systems 5.6 manual NetApp, Creating a VDI using the CLI