Setting up dev and test environment - network question

Question

Hello,

I want to setup test and dev environment which will be identical to production environment. All the environments are behind a router and has many VMs To reduce configuration burden, can I have the same IPs (private IPs or machine names)? Meaning suppose I have 3 VMs in each environment a weblogic, a database, and a CAS VM. All are behind a router. Only entry to any environment is via router external IP address. Can I assign same IP (say 192.168.4.32) or same machine name (say cas1) to all my CAS VMs, irrrespective of environment? This will reduce the configuration that I will have to maintain. e.g. weblogic server server will access database using database1 (or 192.168.4.31 IP) etc. I can even perform a release just by imaging my VMs..

Is this possible? what will be constraints?

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