What is the MTBF on a HP BF146DA47C 146GB 15KRPM drive?

[Raymond E. Lilly]

I installed an EVA4400 mid-October 2008. Since then I have had 4 disk failures. The drives are HP BF146DA47C 146GB 15KRPM 2GB FIBRE CHANNEL DUAL-PORT 3.5" HARD DRIVE. 4 failures seems abnormal to me. Does anyone know the rated MTBF on these drives? Anyone have similar experience?

[hvhari]

I have not seen any MTBF rating specific to hard disks in the EVA.

Coming to EVA4400, there were some firmware related issues (for earlier releases of this EVA Model), which were marking the disk drives bad, though they were good. This has been corrected in later. Current firmware is XCS09534000 which is quite stable. If you have observed frequenty disk failures, even with this firmware , you should log a call with HP to find out if there is some thing wrong.

[Víctor Cespón]

4 disks in 2 years and a half seem too much for you? :O

We replace dozens of disks on EVAs every day, they are mechanical disks, are expected to fail, that's why RAID 5 or 1 is used.

Have you at least updated controllers to XCS 09534000 and disks to latest firmware?

[Raymond E. Lilly]

I opened an HP support call. Let's see what they have to say about MTBF.

Regarding firmware, I keep up on the Controller Firmware.
Version: 09534000
Build: CR18CBlep-09534000

The drives are a different story. Disk Firmware Versions range from HP01, HP04 and HP06

[Cass Witkowski · Accepted solution]

Disk these days have a MTBF of 1,200,000 hours. To translate this into annual disk failure rate take the number of hours in a year (8,760) and divide by 1,200,000 = 0.0073. Take this and multiply by the number of disks you have, say 50 and you get a failure rate of .365 disks per year.

So based on this you should have only lost about 1 disk in this time frame.

Please note that electronic componnets have a typical bathtub failure profile. There is a higher failure rate called infant mortality. This happens in the first x months of the devices life.

Once this infant mortality phase is over the devices should settle down into the low failure rate indicated by the MTBF. After about 5 years the electronics will start to wear out and you will start seeing a high failure rate.

One thing that can dramatically effect failure rates or reduce the life of disks is the tempurature that they operate at. Depending of the operating tempurature one disk manufacture said that the disk drive lifetime could be reduced from 5 years to 3.

While this doesn't answer your question directly. I hope it gives you a feel for what to expect.

Also you need to be running the latest version of the EVA 4400 firmware. Older versions may have marked disks as bad when they were in fact good.

Cass

[Torsten.]

Regarding firmware:

Here is the list of the current versions:

http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?lang=en&cc=us&prodTypeId=329290&prodSeriesId=3302267&swItem=co-87106-1&prodNameId=3351789&swEnvOID=54&swLang=13&taskId=135&mode=4&idx=1


For BF146DA47C latest is HP07.

[Raymond E. Lilly]

Thanks everyone. Great information as usual. Recommendation from HP is firmware, firmware, firmware... No MTBF provided. I will consider updating the drives when time allows.