topic Re: Temperature Sensor Ambient in ProLiant Servers (ML,DL,SL)

Temperature Sensor Ambient

GustavoAyala — Thu, 09 Oct 2014 17:56:29 GMT

I have 2 Proliant DL380P Gen8 with iLO 2.02. Same exact model, one racked on top of the other.
This a a far datacenter, I don't have physical access.

The 01 temperature sensors are displayed differently and with very different temperature and acceptable range.
One is "01-Inlet Ambient" and the other "01-Front Ambient".

I have someone in the remote datacenter to check air blockage in the front, and they tell me they are unblocked and freem and supposedly "breathing almost the same cooled air" from the rack.

Anyone have any clue why they are displayed and named differently, displaying different values and ranges?

Server 1

Server 2

Re: Temperature Sensor Ambient

cykVM — Fri, 10 Oct 2014 02:57:03 GMT

Are both servers on the same BIOS/System ROM version? iLo reads the sensor values (and probably also the naming) from BIOS as far as I know.

Re: Temperature Sensor Ambient

GustavoAyala — Fri, 10 Oct 2014 10:28:02 GMT

Yes of course, both same bios.

System ROM P70
System ROM Date 02/10/2014

Both have SPP 2014.06

I still have to try SPP 2014.09, haven't tried it yet, but I don't think it will do much.

Re: Temperature Sensor Ambient

gsb_2 — Fri, 10 Oct 2014 21:28:16 GMT

My six Gen8s all say inlet ambient and all read about 25C.

15C is below 60F. That would be a real ice chest for a computer room.

Re: Temperature Sensor Ambient

cykVM — Sat, 11 Oct 2014 03:04:22 GMT

Same for my DL380e Gen8 with iLo fw 2.02.

In iLo firmware revision history I read something about "The IPMI Get Sensor Reading command returns incorrect data for the Inlet Ambient sensor" which was fixed with version 1.40 (Feb 2014). See http://h20566.www2.hp.com/portal/site/hpsc/template.PAGE/public/psi/swdDetails/?sp4ts.oid=5177958&spf_p.tpst=swdMain&spf_p.prp_swdMain=wsrp-navigationalState%3Didx%253D%257CswItem%253DMTX_aec396669714428ca923024579%257CswEnvOID%253D4064%257CitemLocale%253D%257CswLang%253D%257Cmode%253D5%257Caction%253DdriverDocument&javax.portlet.begCacheTok=com.vignette.cachetoken&javax.portlet.endCacheTok=com.vignette.cachetoken

Could you confirm that 2.02 is correctly installed/flashed and active on the server showing "01-Front Ambient"?

Re: Temperature Sensor Ambient

waaronb — Wed, 15 Oct 2014 21:04:50 GMT

There is also a new BIOS for the DL380p Gen8, version 2014.08.02

I don't remember what the release notes said but check it out and see if it lists something about the temperature readings.

For what it's worth, on my racks of equipment, the ambient temp readings are usually different by 5C plus or minus, even when they're on top of each other like yours. I don't think the sensors are all that accurate and they're probably not calibrated very well, if at all, during the manufacturing process. It's close enough to let you know if it's overheating, or to track long term trends on the same server, but I wouldn't treat it like it was exact.

It's like the old saying: a man with a watch knows what time it is. A man with two watches is never sure. :)