VMware : Linked Clones

The Linked clones concept is similar to the normal VM cloning process, but with a storage saving twist ;)

When we create a linked clone, a new VM is created from a base VM , at the same state. This clone with use the base VM's hard disk for all read operations, however all writes to the disk ie any change to the data from the original disk is written on a new disk. This is very similar to the concept of snapshots where the original VMDK is read only and all subsequent writes are done to a delta disk.

The main advantage of using Linked clone is to avoid deduplication of data. You can have n number of VMs created from the base virtual machine, but the base disk remains the same. This will considerably reduce the disk space usage, especially in cases like web server farms with multiple servers

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