We have one GroupWise 7 server, I will like to move it over to a cluster

This is the setup..

Server 1
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GWIA
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MTA (1)
POA - 150 users.
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MTA (2)
POA - 150 users.

What is the best thing to do? Have one MTA and under that two POA, or just
move like it is..

What about the GWIA? Is that a good idea to have it on the same cluster?

Thanks…