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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-config parameter 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:allocation controls whether the VDI volume is provisioned as a thin volume or not.
Setting sm-config:allocation=thin will 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-percentage specifies the amount of space, in terms of percentage of
volume, to reserve for volume snapshots.
sm-config:snap-depletion specifies the snapshot space recovery policy action taken when the space
reserved for snapshots has been exceeded. Setting sm-config:snap-depletion=delete-oldest
deletes the oldest snapshots until sufficient space is recovered (the default).
Setting sm-config:snap-depletion=volume-offline sets 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 Appliance™ (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.