[AusNOG] Global switch Level 4 Hard disk's

[John Edwards]

On 13 Jan 2014, at 2:00 pm, Brad Gould <bradley at internode.com.au> wrote:

> Sudden pressure increase or temperature drop with a gas dump?
> 

I’m with Brad,

Gas expansion is an endothermic process. 

The temperature will drop significantly - more than you could effect with a block of ice. In a data centre, the air temp will be back to normal in one cycle, so humans may not notice the difference.

Disks are spinning at 10K rpm, operating at 55 degrees. It’s not surprising that they would fail with a sudden drop in temperature. 3.5” SATA drives are going to be hit harder than 2.5” SAS drives, simply because they are bigger and will contract further.

Pressure increase on a gas drop will be negligible, and most hard drives are effectively sealed anyway.

Someone hit a hot hard drive performing a transfer with a CO2 fire extinguisher, and let us know the result :)

John