[iamjason89]

"The auditor began digging, speaking to many people in West Virginia state government who had been involved with the project. The Department of Education told him that it "did not request or require that the routers for the state's schools have internal dual power supplies. Education would not have made this requirement because unless a school has two power sources the feature of dual power supplies would have no use." A network engineer for the Department of Education confirmed that he had not requested such a feature."

Education would not have made this requirement because unless a school has two power sources the feature of dual power supplies would have no use.

Oh is that how redundant power supplies work? You need two power sources, eh?

[caw]

For full redundancy, yes.

You get redundant power supplies by plugging both into the same power feed.

However, you can gain some extra redundancy by plugging each power supply into a different circuit, and reducing the common point of failure (shared power source).

[nickzoic]

Two UPSes.

Although I've got a good war story on that one too, I had a machine with redundant PSUs emit a stream of smoke from one of the PSUs. It was happily up and serving while smoking out the machine room until the operator (rather sensibly) grabbed both power leads and pulled, at which point both fire and ssh went out ...

[bd_at_rivenhill]

It is if you are in a situation in which the building power source is much, much more likely to fail than the power supply is, which is definitely the case in a rural school or library. You have to get to a pretty high level of sophistication (i.e. backup generators with automatic failover) before a redundant power supply has any value.

[hmottestad]

It would kinda be like buying a really expensive 24 port router and then just using 2 ports.....oh wait....that's what they did already.

Dual power supplies is a bit overkill. Although I remember my high school admin got a central router with dual power supply, but when you plugged both in at once (from the same source) they drew too much power on a reboot and flipped the fuse after every blackout.

[nickzoic]

shrug If you want it to actually work, all the time, go with dual hotpluggable PSUs on everything every time. And two separate UPSs.

If the cheapest router Cisco has with dual PSUs is a 39xx, well, I guess that's what you need.

Of course, there's an argument there that "99.999% uptime" is pretty pointless for a town library in the middle of nowhere, but that's a whole 'nother argument.