Hardware Thread, Quantum LTO 3_HH Drive Temeprature in Technical; Does anyone here run a Quantum LTO-3 tape drive (or LTO-4, or LTO-5 for that matter)?
I have recently installed ...
23rd February 2012, 05:21 PM #1
- Rep Power
Quantum LTO 3_HH Drive Temeprature
Does anyone here run a Quantum LTO-3 tape drive (or LTO-4, or LTO-5 for that matter)?
I have recently installed a new Quantum LTO 3 HH tape drive into our tower server alongside the existing LTO 2 drive.
It works well, backs up at 3 GB a minute or more, and is blissfully quiet - too quiet in fact.
The old LTO-2 drive has a small cooling fan at the back which whines away whenever it is running, but stays cool.
The new LTO-3 drive has no fan that i can see, and seems to run very hot - so hot in fact that I cannot hold my hand on the top of the unit when it is running, whilst the tape cartidge also feels hot after half an hour or so. I can also smell the hot tape!
(The data sheet says that it requires 30 CFM of air, but there is not a breath of air flowing in or out of the drive.)
I have installed X-Talk, which reports drive temperatures in excess of 60 °C after half an hour of running in a room where the ambient is about 18 °C.
The crunch is that the new drive swallowed an LTO 2 tape directly after running a full backup onto an LTO 3 tape (presumably becuase of heat). Quantum have replaced that drive, and have said that it should not get that hot, but the new drive does exactly the same.
Surely two drives cannot be faulty?
If anyone else is running one of these drives I would be grateful for any comment.
Both are internal drives. The LTO-2 is SCSI, whilst the LTO-3 has a SAN interface. I haev connected both the Molex and SATA power cables.
Thanking you all in advance.
4th March 2012, 09:51 PM #2
- Rep Power
To follow up on the above, it seems 'B Series' Quantum LTO 3HH internal tape drives do not have their own cooling, but instead rely on the cooling provided by the host computer.
This is all very well on older machines which pump a lot of air, but most modern PC's and servers are designed to run cool, with minimum airflow to minimise energy consumption and noise.
I have looked at the data for the HP LTO 3 HH internal drives, (which look identical to me). HP make it clear that a minimum airflow of 5 Cubic Feet per Minute must be provided by the system fans to keep the tape drive cool. Quantum, by contrast, only state that 5 CFM airflow is required, front to back – not that this airflow must be provided by the system fans.
(The figure quoted for the Quantum LTO 2 HH drives is 9 CFM, front to back – but this is provided by a fan built in to the tape drive itself. The LTO 3 drive has no such provision.)
It looks as if we will have to buy an external LTO 3 drive with it's own cooling built in, as the internal LTO 3 drive overheats on anything other than an incremental backup, and has already eaten two tapes.
This seems to be a serous oversight on an expensive piece of hardware, especially given the very low air volumes now required for cooling desktop machines and tower servers. It looks to me as if the bean counters have been doing some 'value engineering', and are probably congratulating themselves on saving 50 pence per unit on cooling fans.
5th March 2012, 12:25 PM #3
We have a quantum LTO4 and as far as I can see it doesn’t have a fan, you are correct in that I think our old LTO2 did have one but I have not had any problems with our drive.
“Surely two drives cannot be faulty?” Depends if they are from the same batch if the serial numbers are similar then it’s more likely.
It sounds more like a problem with your server room temp / poor case design.
Does your server room have air con? If the ambient temp is too high it won’t make any difference how many fans your server has because they will be sucking in hot air. Your server room should ideally be approx 18-22c even on a hot day.
Our server with the lto4 is getting on a bit now but it only has one case fan on the back, a fan on the hdd bay and the usual psu and cpu fans. Can you fit more / better fans in the server case?
You should be able to get external drive bays but the fans on them are tiny so don’t expect them to keep the drive cooler than in a server case. A 12cm case fan will pull far more air than the tiny things that are fitted in drive bays.
5th March 2012, 09:35 PM #4
- Rep Power
Thank you very much for your comments.
Originally Posted by ToyHeartsFan
The server is a new Fujitsu machine, and is located in an office at 'office' temperatures. We don't have air conditioning so summertime temperatures are likely to reach 28 °C or so on a hot day. This has never been a problem in the past.
The fans in our old Dell PowerEdge 1600 SC were quite noisy. They didn't blow that much air but made a lot of mechanical noise, so the server was relegated to an old boiler house where nobody could hear it. However, this was far from ideal from other points of view, especially when it came to feeding it with tapes!
Like most tower servers nowadays the new Fujitsu machine is extremely quiet, (quieter even than the HP Desktops that it serves), so the decision was made to bring it in from the cold so it was more secure and easily accessible.
Our old Quantum LTO 2 HH drive worked perfectly well in the new server. The fan did make a bit of a racket whilst it was working, but that didn't matter as our backups are scheduled to start at midnight, and are completed long before anyone is around to complain about the noise.
You are right that large fans spin slowly and can move a lot of air with minimal noise; but I doubt that they create sufficient wind pressure to pull the required volumes of air through the confines of a half-height tape drive, even though the Quantum 'B' series drives have clearly been redesigned with ventilation in mind. A small fan running at high speed moves less air, and makes more noise, but does create higher wind pressure. (And 5 cubic feet of air a minute is a lot of air to pull through a tape drive.)
I suppose it would be possible to fit an additional fan into the server, but that would increase noise, and in sucking air out of the box would reduce air flow through the power supply, which doesn’t seem like a good idea to me. Alternatively, I could disable BIOS control of the existing three fans, but that would make the machine unnecessarily noisy, and from what I can see, still wouldn't provide the pressure differential that is needed across the tape drive to keep it cool.
However, what both puzzles and concerns me is that Quantum clearly saw the need to provide active cooling in their earlier LTO drives, (even though servers and PC's of the day moved a lot more air), which meant that the drives could be fitted into any vacant 5¼ inch drive bay without fear of overheating, but they have removed the cooling system from recent drive models without telling anyone! (Remember that these tape drives are marketed for use in both file servers and desktop machines, so airflow cannot be guaranteed.)
The difficulty I have is that the drives themselves have not failed (yet), but they have now broken two tapes, as the ultra-thin tape material simply cannot cope with the 65 °C plus working temperatures inside the drives.
The obvious solution is to switch to an external drive with built in cooling, but I would need to convince somebody at Quantum that this was justified to allow me to 'trade up' so to speak. The technical support representative that I spoke to was very helpful, but didn't seem to understand the issues involved, and had clearly never actually fitted one of these drives himself.
By kevin_lane in forum Learning Network Manager
Last Post: 19th March 2012, 01:33 PM
By PrimaryTech in forum Hardware
Last Post: 26th April 2011, 03:54 PM
By Simcfc73 in forum Classified Adverts
Last Post: 22nd February 2010, 03:49 PM
By Geek_of_HeathMount in forum Hardware
Last Post: 27th November 2009, 10:42 AM
By markwilliamson2001 in forum Hardware
Last Post: 7th July 2008, 09:09 PM
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Tags for this Thread