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I'm running OS X 10.8 Mountain Lion on several servers. We're about to ship them off to a colo provider, and I wanted to prevent them from sleeping.

My question is, does setting the System Preferences > Energy Saver > Computer Sleep option to 'Never' reliably prevent sleep?

I noticed yesterday that all the mac minis were off, despite the 'Never' option being set. However, I'm thinking their power strip may have just been accidentally unplugged for a second.

marked as duplicate by bmike Oct 3 '14 at 18:23

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up vote 1 down vote accepted

Yes. This setting reliably prevents a Mac from sleeping. I've had my iMac set to "Never" sleep for over a year, and it's still running (though its display turns off after 10 minutes or so per the other setting on that screen).

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