I have a couple of Dell 1U rackmount servers that I need to temporarily move out of a rack.
Is it bad for them to be stacked on top of eachother?
Not really. I’ve got 4 Dell PowerEdge servers stacked one on top of another right now. There’s really no risk of collapsing the bottom servers from the weight of the top servers and there’s really no risk of overheating, as the servers draw cool air in the front and exhaust hot air out the rear.
The risk is that the platform you’re putting them on could collapse if it can’t bear the weight of the servers. The only other issue, as jscott pointed out, is the inability to access the innards without moving them off of each other.
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