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This isn't even remotely close. Unless all 32 servers have redundant AC power feeds present, you've traded one single point of failure for another single point of failure.

In the event that all 32 servers had redundant AC power feeds, you could just install a pair of redundant DC power feeds.



>Unless all 32 servers have redundant AC power feeds present, you've traded one single point of failure for another single point of failure.

Is this not standard? I vaguely remember that rack severs typically have two PSUs for this reason.


It's highly dependent on the individual server model and quite often how you spec it too. Most 1U Dell machines I worked with in the past only had a single slot for a PSU, whereas the beefier 2U (and above) machines generally came with 2 PSUs.


But 2 PSUs plugged into the same AC supply still have a single point of failure.


Which is why you have two separate PDUs in the rack which are fed by different power feeds and you connect the server's 2 PSUs to opposing PDUs.


This works brilliantly, right up to the point where your A side fails, and every single server suddenly doubles their demand on B.

Better have good capacity management so you don't go over 100% on B when that happens! (I've seen it happen and take a DC out).


Rack servers have two PSUs because enterprise buyers are gullible and will buy anything. Generally what happens in case of a single PSU failure is the other PSU also fails or it asserts PROCHOT which means instead of a clean hard down server you have a slow server derping along at 400MHz which is worse in every possible way.


you could have 15 PSUs in a server. It doesn't mean they have redundant power feeds




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