It happens during system start before raid array assembly and before OS boot On May 15, 2016 8:34 AM, "Josh Luthman" <[email protected]> wrote:
> How would staggered drive start up work? Or is the array not available > until the timer is done? > > Josh Luthman > Office: 937-552-2340 > Direct: 937-552-2343 > 1100 Wayne St > Suite 1337 > Troy, OH 45373 > On May 15, 2016 1:01 AM, "Josh Reynolds" <[email protected]> wrote: > >> A lot of the dell servers I use, as well as a lot of the supermicro >> servers have that as well. Thankfully many of the RAID JBOD cards I >> use (softraid ftw, and zfs doesn't like it either) can also stagger >> drive startup. >> >> On Sat, May 14, 2016 at 11:13 PM, Faisal Imtiaz >> <[email protected]> wrote: >> > It would be interesting to note that, we are putting in some new >> servers, >> > and in the bios these have a setting that delays a random amount of time >> > between 50 - 120seconds, before returning to power on state after a >> power >> > loss ..... >> > >> > :) >> > >> > Faisal Imtiaz >> > Snappy Internet & Telecom >> > 7266 SW 48 Street >> > Miami, FL 33155 >> > Tel: 305 663 5518 x 232 >> > >> > Help-desk: (305)663-5518 Option 2 or Email: [email protected] >> > >> > ________________________________ >> > >> > From: "Chuck McCown" <[email protected]> >> > To: [email protected] >> > Sent: Saturday, May 14, 2016 11:40:09 PM >> > >> > Subject: Re: [AFMUG] Data center temperatures >> > >> > I remembering being at a data center on a hot summer day. Power went >> out, >> > generator started. Things were fine... then all the air conditioners >> > switched on at the same time. Actually stalled the generator. We had >> to >> > put sequencers on the AC. >> > >> > From: Faisal Imtiaz >> > Sent: Saturday, May 14, 2016 9:20 PM >> > To: [email protected] >> > Subject: Re: [AFMUG] Data center temperatures >> > >> > FYI, Electrical Code (NECA) and most datacenters require the power not >> to be >> > loaded beyond 80% of breaker capacity... i.e. 16amp draw on a 20amp >> circuit. >> > >> > Additionally, one also has to have head room on the power circuit to >> deal >> > with start up draw (current rush). It's not pretty when you have a crap >> load >> > of servers starting up all together >> > >> > >> > :) >> > >> > Faisal Imtiaz >> > Snappy Internet & Telecom >> > 7266 SW 48 Street >> > Miami, FL 33155 >> > Tel: 305 663 5518 x 232 >> > >> > Help-desk: (305)663-5518 Option 2 or Email: [email protected] >> > >> > ________________________________ >> > >> > From: "Eric Kuhnke" <[email protected]> >> > To: [email protected] >> > Sent: Saturday, May 14, 2016 7:50:22 PM >> > Subject: Re: [AFMUG] Data center temperatures >> > >> > How does a 44U cabinet need 208V 60A for storage arrays? >> > >> > In a 4U chassis the max hard drives (front and rear) is about 60 x >> 3.5"... >> > >> > Say each drive is 7.5W TDP, that's 450W of drives. Add another 200W for >> > controller/motherboard and fans. 650W in 4U. >> > >> > 44 / 4 = 11 >> > >> > Multply by 650 >> > >> > 7150W >> > >> > More realistically with a normal amount of drives (like 40 per 4U) a >> single >> > 208 30A is sufficient, >> > >> > 208 x 30 = 6240W >> > >> > Run at max 0.85 load on the circuit, so >> > >> > 6240 x 0.85 = 5304W >> > >> > In a really dense 2.5" environment all of the above is of course >> invalid, >> > you could probably need up to 7900W per cabinet >> > Then there's 52U cabinets as well... >> > >> > On May 13, 2016 6:16 PM, "Paul Stewart" <[email protected]> wrote: >> > >> > Yup … general trends on new data centers are pushing those temperatures >> > higher for efficiency but also with better designs .. >> > >> > >> > >> > One of our data centers runs at 78F and have no issues – each cabinet is >> > standard 208V 30A as you mention but can go per cabinet much higher if >> > needed (ie. 208V 60A for storage arrays) >> > >> > >> > >> > From: Af [mailto:[email protected]] On Behalf Of Eric Kuhnke >> > Sent: May 11, 2016 5:15 PM >> > >> > >> > To: [email protected] >> > Subject: Re: [AFMUG] Data center temperatures >> > >> > >> > >> > There have been some fairly large data set studies done shown that air >> > intake temperature for huge numbers of servers, at 77-78F does not >> correlate >> > with a statistically significant rate of failure. >> > >> > >> http://www.datacenterknowledge.com/archives/2008/09/18/intel-servers-do-fine-with-outside-air/ >> > >> > >> http://www.datacenterknowledge.com/archives/2012/03/23/too-hot-for-humans-but-google-servers-keep-humming/ >> > >> > how/what you do for cooling is definitely dependent on the load. >> Designing a >> > colo facility to use a full 208V 30A circuit per cabinet (5.5kW) in a >> > hot/cold air separated configuration is very different than 'normal' >> older >> > facilities that are one large open room. >> > >> > >> > >> > On Wed, May 11, 2016 at 1:58 PM, Ken Hohhof <[email protected]> wrote: >> > >> > I’m not sure you can answer the question without knowing the max heat >> load >> > per cabinet and how you manage airflow in the cabinets. >> > >> > >> > >> > AFAIK it used to be standard practice to keep data centers as cold as >> > possible without requiring people to wear parkas, but energy efficiency >> is a >> > consideration now. >> > >> > >> > >> > >> > >> > From: That One Guy /sarcasm >> > >> > Sent: Wednesday, May 11, 2016 3:51 PM >> > >> > To: [email protected] >> > >> > Subject: Re: [AFMUG] Data center temperatures >> > >> > >> > >> > apparently 72 is the the ideal for our noc, i set our thermostat to 60 >> and >> > it always gets turned back to 72, so i just say fuck it, I wanted new >> gear >> > in the racks anyway >> > >> > >> > >> > On Wed, May 11, 2016 at 3:46 PM, Larry Smith <[email protected]> wrote: >> > >> > On Wed May 11 2016 15:37, Josh Luthman wrote: >> >> Just curious what the ideal temp is for a data center. Our really nice >> >> building that Sprint ditched ranges from 60 to 90F (on a site monitor). >> > >> > I try to keep my NOC room at about 62F, that puts many of the CPU's >> > at 83 to 90F. Many of the bigger places I visit will generally be 55 to >> > 60F. >> > Loads of computers (data center type) are primarily groupings of little >> > heaters... >> > >> > -- >> > Larry Smith >> > [email protected] >> > >> > >> > >> > >> > >> > -- >> > >> > If you only see yourself as part of the team but you don't see your >> team as >> > part of yourself you have already failed as part of the team. >> > >> > >> > >> > >> >
