Redundant Power Supply Question

[Chiefcrowe]

So I was wondering, if I have a server with redundant PSUs, then how do they work -

does the server use one as the "main" psu and then only turn the other one on if the first one fails? Or, are they both used simultaneously with the power split between them, and then if one fails the 2nd takes all of the load?

 

[BlahBlahYouToo]

Originally posted by: Chiefcrowe
So I was wondering, if I have a server with redundant PSUs, then how do they work -

does the server use one as the "main" psu and then only turn the other one on if the first one fails? Or, are they both used simultaneously with the power split between them, and then if one fails the 2nd takes all of the load?

it's for redundancy.

 

[imagoon]

Originally posted by: Chiefcrowe
So I was wondering, if I have a server with redundant PSUs, then how do they work -

does the server use one as the "main" psu and then only turn the other one on if the first one fails? Or, are they both used simultaneously with the power split between them, and then if one fails the 2nd takes all of the load?

Depends on the server.

Dells (at least 2800 series and above) split the load. I have first had experience with this.... unplugged "rail 1" on our rack, then proceeded to pop the breaker on the second rail when the full load failed over.