Data Center Cluster Hardware Upgradaton

Hi,

We are running a data center with multiple set of clusters with application, now some of the cluster hardware is not performing well so we are planned to upgrade the cluster server hardware.

All Cluster are running in windows server 2008 SP2, SAP Application is Hardcoded with Host Name and IP Address.

We have different brand of hardware and storage in isolated & production network.

Is it possible to do the same with Isolated Network? How can we achieve this with minimal downtime?

we need to configure cluster in isolated network and move to production with same hostname & IP address.

Thanks in Advance,

Thanks & Regards, Kesa_Kara