Posts by nucotech

Electrical box fault blamed for GS2 data centre outage

Hi,

You have to be careful putting a UPS into a rack enclosure/data hall (ie not do it). UPS rooms are separate to data halls for a reason. Tier IV recommends at least two hours fire rating between power infrastructure and data halls. USP systems and batteries should be checked at least twice yearly and terminal torques at least every few years.

Batteries are a self contained ignition source. This means that you can put a fire out and it will come back. Data halls tend to be protected by an inert gas which once discharged has to then be refilled. This means if you had a battery fire in a data hall the gas would discharge and then if the a battery reignited there would be nothing to stop it and you could lose all your data. This is also why gas suppression in a battery room has limited benefit without automatic link breakers (ie reduce the voltage in the string).

Andrew

We suck? No, James Dyson. It is you who suck – Bosch and Siemens

The comparison was with VW.

VW cars also passed the tests so the situation is actually quite similar. Just replace the following [COMPANY X] with the respective company name and you will see that the following statement could apply to either situation (if' this allegation is correct).

"[COMPANY X] designed a product which used technology to pass official tests/standards designed to calculate its environmental impact. However its actual performance in 'normal' use was/is much higher."

Bosch does however differ in that you can 'use' the product (if you have little or no dust and keep the bag empty) whilst it is stated that the VW cars would struggle to pass in any real world situation. It all depends if having little dust is a real world situation for most users and how much more power it actually uses if it is an exact match or similar.

If it is all ok then Dyson will be clear to implement their own chip which changes the consumption during tests (sorry based on dust levels) which may defeat the entire point of the tests but will be the same for all but I imagine at this point the goal posts will mysteriously move again.

Eurozone crisis: We're all dooomed! Here's why

Good article. We now just need to get the politicians to realise what everyone else here worked out quite some time ago.

Virgin Media downed by Manchester arsonists

Paul

No problem.

"Not always possible when hosting 24-7-365 apps and services"

Sorry above should be amended to:

"The whole system ‘should’ also be tested with a full <POWER> shutdown (not simulated) at least every six months."

We do this for both of the (24/7) hosting data centres we own (as well as a genset only test under load every three months) and all equipment keeps working (as it is designed to) but as this is a controlled shutdown so if anything didn’t work as it should you can restore power and sort it so that when/if there is a real power cut everything 'should' work.

The downside of the extra testing is that without the proper equipment there is a higher risk that when the power is restored equipment that has been taken off load and back on again will fail so it can be a difficult balance to reach.

Comfort cooling air con units need a lot of power to initially fire up so if they all fired up at once it may trip the main fuse (depending on the type as some are designed to ignore very short spikes) so it is common to either set them to start up a few at a time or set a trip to leave some off when the power returns. The problem with this is that it relies on someone being there and remembering to reset them.

If the first time they know that the air con is not working is when the servers start turning themselves off then much of the damage is already done. IP based single temperature monitors that send reports at high and critical levels are less than £300 so can be a good investment.

Not really a data centre then

As a minimum personally I would not consider it a proper data centre without full UPS/generator back up.

As I am sure most of you are already aware. The generator feeds the UPS on the essential circuit for the equipment and the air con units come straight off the generator via a ‘non-essential ‘circuit with air con starting in sequence to avoid overload as they fire up. So aircon ‘should’ only be down for a few minutes whilst the generator fires up and stabilises.

The temperature will increase quite quickly during this time but still within acceptable margins and only for a few minutes. The whole system ‘should’ also be tested with a full shutdown (not simulated) at least every six months.

“Admitted the horse has now already bolted but perhaps its time to look at installing a door and perhaps checking that it closes once in a while.....”