Fans are much louder than normal

[Erik Spigle]

We have 3 DL385s among other servers in our server room (about 12 or so servers total). The DL385s are isolated from the rest of the servers in the room, so we can address them seperately. All 3 servers are slmost identical--2 Operon 270s each, 2x76GB HDs (RAID1), redundant PSUs, and RAM. One server has 2x2GB, one has 2x2GB | 1x512MB, and the last was just upgraded this weekend--4x2GB, 4x512MB.

Before this weekend the last server had 4x2GB and 2X512MB for memory. It has the extra 1GB total added. We never noticed anything when we did the upgrade over the weekend. Also, I didn't visit the server room the Monday and Tuesday after the upgrade, so I can't say I noticed anything. My support tech said he doesn't recall hearing anything though. Today, though (Wednesday), we noticed a very profound difference. One of those servers was about to launch into orbit. Its fans were spinning considerably faster. We *think* we isolated the louder fan noise to the last server I mentioned with all of the memory in it, and the only one we have actually done anything to in a while--the memory upgrade. Is there any reason that adding that extra 2x512 would trigger the server to spin its fans faster? And if so, why only after a few days?

We can't figure out anything about what could be causing this. CPU usages seem to be acceptable (pretty low overall). The server is a VMware ESX server. All of the hosted guest operating systems (only 4 right now) showed little CPU usage. The CPUs didn't feel hot when we felt them. Nothing in general felt really hot. Clearly, though, the server is blowing a LOT more air than it has in months past and it is much much louder than ever before (we had people asking why the server room was so much louder when we had the door open, and it is very much louder just listening to it down the hall when the door is open). Any guesses or help about this? Is it nothing to worry about? I probaby would have worried so much if this was doing this from day one, but this just started today after several months.

Oh, one last thing. I pulled each fan out individually while the server was running and put them back in. No one fan is considerably louder. They collectively all seem to be spinning much faster in that one server.

Thanks for any guesses or help into what to look into. If you want any more information, let me know.

[Torsten.]

Sounds like a bad fan. If one fan is bad (not turning or to slow) the others will turn faster. If you are running win, take a look at the system management homepage.

[Erik Spigle]

Unfortunately, this server is running VMware ESX 2.5.2, so I have no way to monitor the hardware, really. If it's a bum fan, though, I'll be severely disappointed. This unit has only been active for about 2 months, and here in a few weeks I'll have it at a remote location where I won't have local access to the machine to know if it drops a fan or anything. Knowing a fan went bad in a couple months doesn't settle well. As I unplugged and re-plugged in each fan, they each seem to be responding about the same.

I'll see about swapping all 5 fans after-hours with another one of our DL385s and see if the other server starts doing the same thing. If it does, it has to be a fan as you said. I need to see if there is a way with ESX server to monitor things like fan speeds.

Thanks for the suggestion--I'll look into it.

[David Claypool]

What do you mean there is no way to monitor the hardware? HP System Management Homepage package is available for ESX. Go to http://www.hp.com/servers/swdrivers and select ESX as your OS to download the package.

[nurascorpio]

Boot the server with the SSCD - Maintenance - Diagnose Server - select complete tests.

It will check all the hardware components and give you the result - to check any degraded hardware or failed components.

Please check this - http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=PSD_EL050819_CW01

[Erik Spigle]

My apologies--I said that in ignorance. I think right after posting that nothing existed for ESX from HP, I looked for downloads for the DL385 and realized I looked over the ESX entry. I picked up the ESX software and installed it last night. Looks like everything is good for monitoring now. As part of my work, I swapped out all fans in the offending DL385 and put them in a different one. As of last night when I left the office, everything was operating normally. We're still left wondering what might have happened to the original server to cause it to go unhinged with its fans. We'll be keeping a close eye on it, though.

Thanks for the additional info and I'll dig into those things when I get back to the office. Sorry about my oversight.

[Erik Spigle]

nurascorpio: Should this apply to a configuration that doens't include any 4GB modules? I suppose if it's possible that a configuration of 4x512MB + 4x2GB could cause it to get hot enough to crank the fans up a notch--that might be my issue. The server really isn't under much load, though. I'll keep an eye on it.

[Erik Spigle]

I believe the issues were a combination of a server room which was getting too warm (had someone come out and address that) plus the extra RAM heating things up. Since working with things, I haven't seen any more issues of fans running extremely hard and loud. Thanks for all the help and suggestions.