Hacker News Reader

Comment by nsteel | Hacker News Reader

Carrier-grade (i.e. critical) network equipment should be rated for 40C ambient air and then up to 55C for some short length of time (3 days??) to allow for air conditioning failure. This is what we design and test for. Cheap stuff, including Google's software solutions running on 'commodity hardware', won't handle that. You get what you pay for.

View on HN

I have not seen a lot of carrier equipment in the DC/CO rated to 55C. Optical transport nodes maybe but not the Switches and Routers and servers etc. Temp ratings like that are normal for field systems in passively cooled cabinet shelters or tower sites and Industrial Ethernet and CCTV camera housings etc are even built to handle 65C. The Uptime Tier-1/2/3/4 builds overcapacity redundancy into the cooling facility itself to avoid failures like this and I don't recall seeing anything NEBS related to go beyond that either. This looks like it was a matter of intake air/water to the cooling system going outside of design parameters so even with extra capacity they couldn't meet the t/h set points.

I think it very much depends on the equipment. I think we have multiple tiers of what we support at each type of facility, with traditional data centres having less stringent requirements (maybe w.r.t noise/filters rather than temp) compared to the facilities housing big routers where -5/55C is the spec to meet.

You are right, and it's arguably harder for those smaller boxes sitting in cabinets / on telegraph poles, despite being much lower power systems to start with. It might be 50C+ in there before they even turn on! Those things might have a two-stage boot process where they just run their fans for a bit to cool things down before actually booting the main system. It must be a real nightmare for entirely passive stuff, I have no experience with that.

Google doesn't run its networking equipment on commodity hardware. That's been the case for over a decade source from Open Network Summit talks. The issue here isn't about network equipment temperature rating, rather whole datacenter losing cooling.

I was under the impression that they still did some of their own software defined routing, maybe at lower bandwidths? That could be an out-dated view. I do know they also buy traditional equipment from the big vendors for high-bandwidth stuff. P4 is very cool.

I was trying to point out that high-end hardware should survive a couple of days despite a data centre losing its cooling. it is designed for exactly that situation.

a typical google data center has a networking room which often will have large numbers of standard commercial networking devices. That room has extra redundancy, locked off from the cattle, etc.

Does the UK even design with the assumption of air conditioning being necessary and present, let alone designing for it failing?

Datacenters always have A/C I thought?

Thanks :)

Google and other companies do make risk assessments including temperature scenarios.

Yes. You must be able to control the temperature of a building densely packed full of hot radiators. You might be able to avoid active AC within the Arctic circle but you'd m still want to filter that incoming (very) cold air, at which point maybe you might as well basically have an AC system. And yes, you must ensure you can survive a failure because these systems do fail (normally when you need them most) and then otherwise everything inside cooks.

The arctic is warming much faster than other places. See eg this recent article about record 38C temps in siberia: https://www.sciencenews.org/article/siberia-verkhoyansk-reco...

Cheap stuff, including Google's software solutions running on 'commodity hardware', won't handle that. You get what you pay for.

Sounds like the downside of the "pets versus cattle" methodology is that natural phenomenon will wipe out your entire herd, while the pets survive.

Reply on news.ycombinator.com