Duplicate Content - a weapon?

[globay]

Hello, I have some questions:

I am planning to set up a mirror for some of my pages. Will Google ban my site for doing that?

Lets say I built a Sitemap. Now I put this sitemap on different servers, linking one sitemap to another. Will Google ban my site for doing that? Or could somebody report me for spamming?

If Google bans sites with duplicate content. How do they see that the duplicate content was not uploaded by a competitor? This could be used as a weapon, couldn't it?

Of course I would never do that, but I am just curious, if Google thought of that.

Thanks for your replies,

globay

[Robino]

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