-1

We have several rack servers, all with SATA3 Transcend SSD's. Most SSD's are 250GB and they usually have 50% free space most of the time.

When there are unexpected shutdowns, not all the data is properly written to disk, so we can't retreive the data anymore.

The amount of data we write is more or less 8000 rows every 10 seconds. Obviously that the lower the number of rows, the higher the chance for all of them to be written properly. We passed from HDD to SSD for this reason, the maximum amount of rows for a HDD to be all written prperly was around 700, above that quantity the data would be unrecoverable. The SSD's rised this limit to around 5000-6000, but it is not enough.

Is there any solution for this? All the data comes from Ethernet port, I mean there is no data generated locally.

8
  • 3
    What's causing the unexpected shutdowns? That is the question you should be seeking resolution for.
    – EEAA
    May 2, 2017 at 14:02
  • Use a disk controller with FBWC or BBWC
    – Chopper3
    May 2, 2017 at 14:06
  • 1
    So provide decent infrastructure for your product, then. Purchase a high-quality UPS to install and proper battery-backed storage controllers.
    – EEAA
    May 2, 2017 at 15:00
  • 1
    @EEAA they do have UPS, but most of the time they are running out of battery due to the conditions, sometimes servers keep restarting over and over for minutes and thats really harsh for the application. We can neither provide "decent infrastructure" if the client is not willing to pay for it.
    – u1236645
    May 2, 2017 at 15:09
  • 2
    @u1236645 I don't think this issue is yours to fix. You cannot ensure data is written without power going to the devices, it's simply not possible. As others have said, it's the client's job to fix the unexpected shutdowns.
    – Stese
    May 2, 2017 at 16:06

1 Answer 1

5

Why are your servers crashing so often?

In case of power failure:

  • Get a RAID controller with backup battery / capacitor
  • Get SSDs with build in capacitors, so they have time to write their cache
  • Get a UPS to prevent power failures from shutting down servers

//EDIT// As EEAA pointed out below, also connect the UPS to the servers so it can trigger graceful shutdown. Every major UPS provider has solutions for this.

In case of hardware failure get better and/or redundant hardware.

In case of OS crash fix the error resulting in the crash.

2
  • 1
    "Get a UPS to prevent power failures from shutting down servers" It's worth mentioning that unless you have ops staff monitoring things 24x7 and available to shut down infrastructure, the UPS should be configured to do a graceful shutdown of the system.
    – EEAA
    May 2, 2017 at 15:01
  • @EEAA thats a good point, I add it to the answer.
    – mzhaase
    May 3, 2017 at 8:59

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .