There are two options for customizing instant clone virtual machines: VMware ClonePrep or Microsoft Sysprep.
ClonePrep is a VMware customization process run during instant clone deployment to personalize each desktop clone created from the parent image. During the initial startup of each desktop, ClonePrep:
- Creates a new computer account in Active Directory for each desktop.
- Gives the instant clone desktop a new name.
- Joins the desktop to the appropriate domain.
Sysprep is a Microsoft tool to deploy the configured operation system installation from a base image. The desktop can then be customized based on an answer script. Sysprep can modify a larger number of configurable parameters than ClonePrep, but ClonePrep is significantly faster. Majority of instant clone customers choose ClonePrep
The following table lists the main differences between ClonePrep and Sysprep:
| Function | ClonePrep | Sysprep |
|---|---|---|
| Removing local accounts | No | Yes |
| Changing Security Identifiers (SID) | No | Yes |
| Removing parent from domain | No | Yes |
| Changing computer name | Yes | Yes |
| Joining the new instance to the domain | Yes | Yes |
| Generating new SID | No | Yes |
| Language, regional settings, date, and time customization | No | Yes |
| Number of reboots | 0 | 2 |
| Requires configuration file and Sysprep | No | Yes |
| KMS license activation | Yes | No (performed by Agent) |
| Post customization script, pre-shutdown script | Yes | No |
It is recommended that you use ClonePrep unless there are specific Sysprep capabilities required for your environment.
For instant clones and ClonePrep, the table below shows the effect of various operations on SIDs.
| Creation | Push Image | On User Logout | |
|---|---|---|---|
| ClonePrep | Parent Image's SID are used for the desktops | SIDs are preserved unless parent image is changed | SIDs are preserved unless parent image is changed |
