Terraform Scaling VMs

1. Define a var file with a list of objects, e.g. VMname, cpu, etc.
2. Define resource block for VM.
3. Upon apply, VMs are deployed in an order like : web[0], web[1], web[2]
   
4. You can scale up/down from the end, i.e. specify web[3], web[4]. But removal will be LIFO, so web[4], web[3] and so on.

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