VMware Linked Clones is a great technology that creates copies of a Virtual Machine that shares virtual disks with the parent virtual machine. This has two benefits: it conserves disk space creating clones that doesnt consume extra space and they are created instantly, so it is good way to quickly duplicate a VM to test some risky change you dont want to do in production.

This technology is mainly used by VMware in their VDI product Horizon View to create virtual desktops from a shared template. It is not exposed in vSphere UI so the only way to use them is through vSphere API.

Unitrends has a free tool called the Recovery Time Calculator that uses Linked Clones to measure Recovery Time of your services. It creates temporary clones, isolated them from network, poweron based on your dependencies, wait until GuestOS is up and measures the recovery time and successful recovery. After the test is completed the temporary clones are poweroff and removed.

rta_calculator

We have updated the tool and added a new option to maintain Linked Clones and dont delete them after test. Now, you can connect to them, test changes, apply patches and do other tests that are risky to do in production. Once you are done just click on “Remove Clones” button and it will remove them.

Download and test the tool and let us know other uses cases for linked clones you find interesting and what other free tools you would like to see from Unitrends.

Download Unitrends RTA Calculator