The use of virtual machines in a dev/test environment can quickly become a problem with problems related to VM sprawl. One of the downsides of the VM sprawl problem is the use of storage. A VM is usually several GB in size and with VM sprawl, storage of several TB can be used up quickly.
Enter Linked Clones technology, which we have talked about in the past. In virtual lab automation products, this technology helps optimize the use of storage in VMs. If you derive a VM from a base template (which may be a few Gigs in size), make some modifications (like install software etc.) – and capture this as a template in the library — VLA products like VMLogix LabManager will only capture the difference in the new template. It makes a “linked clone” – therefore, the new template is only a few MB in size compared to the base image of several Gigs. This dramatically reduces the storage requirements and optimizes the storage used by VMs on disk.

Understanding Linked Clones
This movie below demonstrates the benefit of Linked Clones.
- Srihari Palangala
Related post: Shrinking VM snapshots of builds and releases.


January 21, 2009 at 3:53 am |
[...] Importance of Linked Clones in Virtual Lab Management [Update - 1/21/2009 - I have made a new post with a demo of the benefit of Linked clones in dev/test environments] [...]
February 12, 2009 at 4:59 am |
[...] Demo: The Benefit of Linked Clones in Dev/Test Environments (also explains what linked clones are) [...]
March 9, 2009 at 5:32 am |
[...] The Benefit of Linked Clones in a Dev/Test Environment [...]