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Power Failures, SSDs and BBUs

Last response: in Storage
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February 5, 2013 7:58:05 PM

Hey all,

Thank you for the resource you all provide.

I have recently had a few power failures at home and my Win 7 desktop has suffered some hiccups. The main hard drive is a Crucial M4 128Gb SSD. The operating system and a few other programs are installed on that disk.

After the power failures the computer will not recognize the SSD boot drive and as a result fails to load windows 7. The standard white lettered message about not detecting a boot drive comes up after Bios loads. Bios also fails to detect the SSD. Luckily for me, after a few, but sometimes many many attempts, the SSD will be detected and the computer will boot as usual.
However, I am very anxious that next time a power failure occurs, the system will fail to recognize the SSD in perpetuity.

In my research so far I have read about something called a Battery Backup Unit. I have no experience with these units and wonder if they will prevent this failure of detection from occurring after a power failure.

What exactly is causing my SSD to hiccup after power failures? Why is the SSD detected after a few reboots sometimes? How can I prevent this from happening at all? Is a BBU a good option?

a b G Storage
February 5, 2013 8:02:34 PM

A battery backup is never a bad idea, especially if you are having brown outs.
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February 5, 2013 8:24:05 PM

The Replicant said:
Hey all,

Thank you for the resource you all provide.

I have recently had a few power failures at home and my Win 7 desktop has suffered some hiccups. The main hard drive is a Crucial M4 128Gb SSD. The operating system and a few other programs are installed on that disk.

After the power failures the computer will not recognize the SSD boot drive and as a result fails to load windows 7. The standard white lettered message about not detecting a boot drive comes up after Bios loads. Bios also fails to detect the SSD. Luckily for me, after a few, but sometimes many many attempts, the SSD will be detected and the computer will boot as usual.
However, I am very anxious that next time a power failure occurs, the system will fail to recognize the SSD in perpetuity.

In my research so far I have read about something called a Battery Backup Unit. I have no experience with these units and wonder if they will prevent this failure of detection from occurring after a power failure.

What exactly is causing my SSD to hiccup after power failures? Why is the SSD detected after a few reboots sometimes? How can I prevent this from happening at all? Is a BBU a good option?


Corruption/loss of meta data(the FTL) causes almost all SSD failures, it's not specifically a result of the power loss but actaully the result of the inability of the SSD to properly manage meta data durring the wear leveling process. When you've got relatively small physical wear on an ssd, recovering to a bootable state is possible because every time the drive is initialized the FTL data is moved. Basically you're very lucky you have a crucial(micron built) ssd that can recover from this state and not a buggy Sandforce Driven POS.
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a b G Storage
February 5, 2013 9:11:19 PM

leonfeldman89 said:
Corruption/loss of meta data(the FTL) causes almost all SSD failures, it's not specifically a result of the power loss but actaully the result of the inability of the SSD to properly manage meta data durring the wear leveling process. When you've got relatively small physical wear on an ssd, recovering to a bootable state is possible because every time the drive is initialized the FTL data is moved. Basically you're very lucky you have a crucial(micron built) ssd that can recover from this state and not a buggy Sandforce Driven POS.


The moral of the story is: Get a battery backup, having the power suddenly cut is not good for SSDs.
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a c 525 G Storage
February 5, 2013 9:50:06 PM

Battery Backup Units (BBUs) are used and connected to high-end RAID controller cards.
When a power failure occurs any remaining data in memory is flushed and written to the drives connected to the controller card so that no data is lost.

What you need to look into is Uninterruptible Power Supply (UPS).
http://en.wikipedia.org/wiki/Uninterruptible_power_supp...

Here are some for sale on Newegg.com: http://www.newegg.com/UPS/SubCategory/ID-72
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February 6, 2013 7:08:03 PM

Excellent. I am looking into a good UPS now.

Thanks for all your help.
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a c 819 G Storage
February 6, 2013 10:13:24 PM

check for a firmware update. My patriot pyro used to display the same symptom until a firmware patch finally fixed it. Its a sandforce drive so it might not apply to your crucial but its usually worth looking into.
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February 8, 2013 2:12:08 AM

leonfeldman89 said:
Corruption/loss of meta data(the FTL) causes almost all SSD failures, it's not specifically a result of the power loss but actaully the result of the inability of the SSD to properly manage meta data durring the wear leveling process. When you've got relatively small physical wear on an ssd, recovering to a bootable state is possible because every time the drive is initialized the FTL data is moved. Basically you're very lucky you have a crucial(micron built) ssd that can recover from this state and not a buggy Sandforce Driven POS.


Yes check for a firmware update. I also had similar issues with my Intel 330 SSD earlier until I applied a firmware patch. My piece of hardware uses a SF controller and this worked for me. You can also try this. Firmware updates usually fixes issues such as these.
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February 8, 2013 4:28:06 AM

steave_01 said:
Yes check for a firmware update. I also had similar issues with my Intel 330 SSD earlier until I applied a firmware patch. My piece of hardware uses a SF controller and this worked for me. You can also try this. Firmware updates usually fixes issues such as these.


A firmware update will restore your drive to a functional state, but a new raw set of translation tables will be generated so you will lose your data.

Just be aware this is NOT a fix for data loss. In fact, unless you have the loader and factory firmwares you can't recover from these instances of meta data loss due to wear leveling bugs on SF driven drives.

Unfortunately, nobody but the drive makers themselves have the loader, so it's truly impossible to recover the data in these cases.

This is true for many non-SF driven SSD's also but there are notable exceptions like the Intel 320 and 520 series drives that a handful of DR companies(3 or 4 that I know of) have developed a work-around to recover the data.
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