Did you check the Polycom RealPresence DMA 7000 System Operations Guide as this covers in a whole section the different types of Upgrade Procedures?
Usually your Polycom reseller should be able to advise you if this is outside your own comfort zone and they should always be able to offer you professional services via Polycom in addition.
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
Polycom Global Services
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