mejv

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Posts posted by mejv


  1. It is fine.

    The media wearout indicator still shows a lot of life left.

    When that reaches 0, and then maybe sometime a long time afterwards .... the ssd may finally be worn out.

    The old 50nm NAND can take a hell of a beating.

    I would agree to that!

    The drive has been proven working, and it still has all its reserved space intact...

    But like any drive, a backup is a good idea!

    MEJV


  2. There's no plug and play compatibility between arrays on the 3ware 9750 and any of the LSI units, right?

    the answer to this question is "No!".

    The 3ware stack of the raid units uses a 3ware specific format, compatible between 3ware models: 9500/9550/9650/9750.

    The LSI MegaRaid used the LSI specific format, naturally not compatible to any other RAID controller brand...

    MEJV


  3. From what I learned over the years, it is common practice, for storage companies, to re-use returned drive that got 'fixed' we replacement drives when a drive under warranty fails in the field.

    Unless it is specified in the contract that a failed drive will be replaced by a brand new one, they usually use a 'refurbished' drive that passed their tests.

    Regards and good luck,

    MEJV


  4. Gentlemen,

    Sorry to tell you that 3ware products before the 9650SE cannot support over 32bits LBA values (over 2 TiB or 2.2TB).

    Also, none of the 3ware products would support 4kB sectors.

    The 9550SX being old, there is no chance they will update its firmware since the product is EOL...

    As far as I know, An Array could go over 2TiB but the OS needs to be able to support volumes > 2TiB to be able to access it.

    Hope this helps!

    Regards,

    MEJV


  5. Hi jump1e,

    The 3ware 9550 PCI-X parallele bus would not support >2TB drives. However, it would support > 2TB raid units (multiple drives < 2TB)

    Its firmware has not been updated up to the 9650/9750 raid controllers.

    Also, this controller is NOT compatible with 32bit PCI bus, only on PCI-X bus. (was there a PCI 64 bit bus ?!)

    Regards,

    MEJV


  6. I believe you could be seeing an issue due to the quick read-modify-write RAID 5/6 are using due to the controller generation/update of the RAID parity.

    Some drives have issues with that..

    The 9690SA does not work with anything 6GB. The controller will fail if direct-attached to 6 GB devices.

    If the slots were not occupied for a long time, the connectors might be oxidized and having contact issues (CRC errors ?)

    Best of luck!

    MEJV


  7. Hi all

    I'm getting the following error in the LSI MegaRAID Storage Manager error log:

    No idea what it means, hopefully someone can advise on what's best to do.

    Many thanks

    One of your drive has a SMART threshold trigger: This is a warning saying this drive is not 100% healthy, backup your data ASAP as the drive might fail soon...

    You need to find out which parameter triggered: Too many bad sectors is the most common one where the drive is getting bad and using its spare sectors...

    Regards,

    MEJV


  8. Hello there!

    The PCIx 9550SX controller from 3ware does not do RAID 6 due to HW limitations.

    (Note that the 9550SX does not support > 2TB drives)

    RAID 5: if X drives in a RAID 5, X-1 drive capacity.

    1x sixteen drive RAID 5 sub-units (+ 0 spare) meaning total capacity of 15* drive capacity = ~15GB

    1x fifteen drive RAID 5 sub-units (+ 1 spare) meaning total capacity of 14* drive capacity = ~14GB plus a spare

    RAID 50 would be space reduced according to how many drives would be grouped in RAID5 the striped in raid 0:

    5x three drive RAID 5 sub-units (+ 1 spare) meaning total capacity of 5*2 drive capacity = ~10GB plus a spare

    (RAID 0)

    / /|\ \

    / / | \ \

    / / | \ \

    / / | \ \

    (R5)(R5)(R5)(R5)(R5)

    /|\ /|\ /|\ /|\ /|\ spare

    DDD DDD DDD DDD DDD D

    4x four drive RAID 5 sub-units (+ 0 spare) meaning total capacity of 4*3 drive capacity = ~12GB

    (RAID 0)

    / || \

    / || \

    / / \ \

    / / \ \

    (R5)(R5) (R5)(R5)

    /||\/||\ /||\/||\

    DDDDDDDD DDDDDDDD

    3x five drive RAID 5 sub-units (+ 1 spare) meaning total capacity of 3*4 drive capacity = ~12GB plus a spare

    (RAID 0)

    / | \

    / | \

    / | \

    | | \

    (R5) (R5) (R5)

    //|\\ //|\\ //|\\ SPARE

    DDDDD DDDDD DDDDD D

    2x height drive RAID 5 sub-units (+ 0 spare) meaning total capacity of 2*7 drive capacity = ~14GB plus a spare

    (RAID 0)

    / | \

    / | \

    / | \

    | | \

    (R5) (R5) (R5)

    //|\\ //|\\ //|\\ SPARE

    DDDDD DDDDD DDDDD D

    Hope this helps!

    Good luck!

    MEJV

    (Darn, can't get the text display properly... Hope you get the picture anyways!)


  9. It would depend on the size of the IOs and the sequential request load vs random as well as read vs write commands.

    A HDD can retrieve (read) small sequential data easily as it would use caching and read-ahead to have the data loaded in RAM to be accessed faster.

    Random writes would be cached and written in the an optimized way to limit head movements.

    So it is very difficult to asses the validity of such test unless you know the exact load pattern...

    MEJV


  10. Confusing ?!:

    1) Bytes and bits

    B is used for Byte

    b is used for bit

    "Maximum media transfer rate: 1638 Mbits/sec" <=== really is 1638 Mb/s

    "Maximum interface transfer rate: 600 Mb/sec" <=== really is 600 MB/s (SATA 6Gb/s ~ 600MB/s)

    2) error rate:

    "Non-Recoverable Error Rate: 1 in 1014 bits read" <== 1 in 10 power 14 or 1 in 100,000,000,000,000 bits

    3) Power

    "Start-up: (W, peak, max) 1.2W (+5V) & 1.5 (+12V) (amps)" ???

    Thanks!

    MEJV


  11. We have amassed many many many USB drives of varying capacities and designs over the last two years or so. See the picture in this article to see only the ones that came out of my desk -

    http://www.storagereview.com/study_shows_alarming_loss_confidential_data_flash_drives

    If you want, you can have them. I'll mail them to whoever responds to this post. The only requirements:

    1) US address only

    2) You don't get to pick ;)

    3) You probably can't have my Transformers USB drive

    4) You must have 10 posts or more in the StorageReview.com forums

    We'll leave this open until the supply is exhausted. Enjoy!

    All right...

    I always seem to misplace my usb stick...

    MEJV

    CA 95132

    Thanks!