Service Manual

Provisioning and Extensibility Overview of Dell VIS Self-Service Creator
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With VMware clones, administrators create a master image (template) and a customization spec within
vCenter. VMware Template clones provide an easy way to build and maintain a master image. VMware
customization specs provide the ability to customize your OS deployments. For Windows OSs,
customization specs also alleviate the need for administrators to sysprep systems and create
potentially complex sysprep.xml or sysprep.inf files.
Requestors may be offered options to customize their workload size to meet their needs. Memory size
and vCPU count may be selected from an administrator defined range. Additionally, administrators
have the option to override the VMware Templates disk allocation methodology to require thick or thin
allocation of storage.
Window specific customization options, including administrator password, domain joining credentials,
license key, and the computer accounts target organizational unit in Active Directory, are set within
the vCenter customization specification. With the use of a custom workflow, a customer specific post-
provisioning script can be executed on the guest operating system.
Linux deployment also utilizes vCenter Customization Specification for basic time zone, DNS, and
domain settings. In addition, VIS Self-Service Creator can execute a customer provided script post-
clone. Administrators specify the script’s path on the clone’s local disk or NFS mount. Since this script
executes within the VIS Self-Service Creator framework, it has access to all custom properties and the
ability to create new properties.
Once the provisioning process is completed, a post-provisioning script may be executed. A common use
for a post-provisioning script is to utilize the custom properties to install workload specific software
such as web servers or database servers. Additionally, these scripts can be utilized to further
automate the deployment process. In some environments, these scripts are used to update network
monitoring systems or inventory databases with key information regarding the newly created workload,
including system owner or user provided description.
vCenter Template cloning is a very disk intensive operation. By default, VIS Self-Service Creator limits
itself to two concurrent clone operations; however this maximum can be increased if needed. To
achieve the best possible clone performance, Dell recommends utilizing storage arrays, like Dell
EqualLogic arrays, that implement VMware vStorage API for Array Integration (VAAI.) VAAI can offload
the clone of the VMware template to the array, resulting in a substantial decrease in clone time and
clone induced network load.
WIM Imaging
Windows Imaging Format (WIM) is a Microsoft specific file-based imaging technology used to deploy
Windows Operating Systems. With WIM imaging, it is possible to deploy Windows XP, Windows 7 and
Windows 2003/2008 workloads to VMware, Microsoft Hyper-V R2, and XenServer Hypervisors.
Preparation
WIM Imaging is a manually intensive process compared to VMware cloning. To create a master image,
administrators typically create an empty virtual machine, then install and configure the operating
system and other applications. Since different hypervisors present virtual hardware differently, it is
recommended for master image creation to occur on the same hypervisor as the workload is targeted
for deployment. For instance, a WIM image created on a Hyper-V Virtual Machine (VM) may not
function appropriately when deployed in a VMware VM.