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CosmicPuppy

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Everything posted by CosmicPuppy

  1. Just sharing the mini-nightmare I experienced this week, in case y'all have any recommendations: I have an IcyDock external 4 drive JBOD array, running SATA disks over its single USB interface because it is connected to an Intel NUC with no eSATA ports (there's one SATA connected to an external BluRay drive). I have a UPS and the array has been running for months with no problems. Early yesterday I had some USB device errors (keyboard or something) and accidentally pull the array's USB cable. Plugged it back in and everything seemed fine ... but not for long. After a reboot, all 4 drives in the array came up with their NTFS partitions marked as "RAW". Geesh! I thought NTFS was more tolerant to a little glitch than that! I felt some comfort that because I had DrivePool with full duplication enabled, I would have two opportunities to recover the data. I purchased "GetDataBack Simple" for this purpose. It recovered most of the folders and files intact, though a few folders lost their names and proper locations in the tree. I recovered by writing to a pair of larger external USB drives already connected to the PC. So... Now I have to put my array back together again... But am rethinking the layout: Since a "hiccup" on the one USB cable and/or chassis has proven that it can destroy both supposedly independent NTFS file systems, obviously one duplicate of each drive should be on a different USB bus ... either a separate chassis or independent external drives. The 4 chassis drives are 1tb each and I have a pair of 3tb external drives. So my plan is to partition the 3tb drives into 3 (1tb, 1tb, and slightly under 1tb), and pair up chassis drive to each partition. But wait ... that doesn't quite balance out! So I guess I could create 1 or 2 Pools and just create balancing rules that ensure all duplicates span across the total of USB ports (1 chassis USB with 4 drives + 2 external USB drives)? Question: Is it possible for a partition (a single NTFS "drive") to belong to more than one Pool? The 3tb drives, for example, could then belong to 1 Pool for mirroring 2 of the chassis disks each, and also belong to a separate Pool to duplicate each other? Of course... I can do the above with partitioning, but since DrivePool uses a top-level NTFS Folder to hold the pooled data, can't it just have 2 (or more!) folders on each single partition, one such folder for each pool the partition belongs to? Thanks for indulging my insanity. DrivePool is a powerful product, so there's bound to be several bad ways and a couple good ways to handle this. I'm presuming that DrivePool itself didn't play any role in the simultaneous NTFS corruption ... but let me know if that is not a safe assumption.
  2. CosmicPuppy

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    Understood. I'm a product manager for a software product, so I know that there are a lot of factors determine if and when features get added.
  3. CosmicPuppy

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    Super, super, super, appreciate this! My requirements for a pool to remain online are not critical for most of my use cases at the moment, so I was still leaning towards DrivePool as my storage management software, but having this functionality supported clinches the deal. There are various scenarios this will be helpful in, even for "planned" disk removal. For example, I could have my Pool setup with 3x duplication so that I can pull a drive at any time to take offsite to secure storage. When convenient, I can then add a replacement disk, and/or permanently change the Pool to 2x duplication. Yes -- there are probably ways to do this step-by-step manually in the current version of DrivePool, but maintaining write capability through unplanned single disk failure is particularly important; even if the side-effect benefits could be accomplished via manual methods. With respect to "complete recheck" -- I agree. When the original or replacement drive is brought online, it is perfectly reasonable for performance to degrade as duplicates are checked and/or rebuilt as necessary. The interim plan is to use AllWay Sync or a similar file comparison+copy/sync utility to bring the new drive up to date in the foreground; having DrivePool do this automatically is a logical feature enhancement. Thank-you very much!
  4. CosmicPuppy

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    I am familiar with AllwaySync, but it doesn't do background duplication (nor pooling). In the RAID systems that I am familiar with, when the system is in degraded mode (i.e, missing a disk for parity or mirror), writes continue to be permitted. If the offline disk is brought online, any files that were updated in the live pool are overwritten on the replaced disk. To avoid sync conflicts, you could either presume that a hot removed drive (or a drive removed during a power down) will not be attached to any other system in write-mode, or the sync could check that all files needing reduplication are of a older date on the target drive (and if there is a date conflict, either reverse the duplication director or record a duplication failure in the log). In other words: Having the pool go "read-only" due to the loss of one drive is confusing to me. I understand there are benefits to this choice, but it is definitely not the behavior that I desire. The reason I use a pool with duplication is to keep the pool fully and automatically available at all times, even if one drive has partially or completely failed or is removed. Is there a configuration option or future feature? Are Windows "Storage Spaces" a better alternative for me? Do you have a pros/cons chart? Thank-you! ...Terry.
  5. Hi, Just installed the Beta (v2.2.651), but my "dpcmd" doesn't have the "check-pool-fileparts" option. Am I missing something? Thanks... Version 2.2.0.651 Usage: dpcmd [command] [parameter1 [parameter2 ...]] Commands: get-duplication - Outputs duplication related information about the specified path. parameter1 - Path to a file or folder on the pool. set-duplication - Sets the duplication count for a folder. parameter1 - Path to a folder on the pool. parameter2 - The duplication count (>= 1). list-poolparts - Lists all of the pool parts that make up a pool. parameter1 - Path to the pool. add-poolpart - Tries to add a pool part to the pool from a path to a volume. parameter1 - Path to a volume. parameter2 - Path to the pool or leave blank to create a new pool. hint-poolpart - Sends a hint to the pooling file system to check this volume for a pool part. parameter1 - Path to the volume.
  6. CosmicPuppy

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    I was about to start a new Topic, but figured I'd find something close already posted. I don't have time to write many details at the moment but would like to understand this issue. And I have only observed this concerning behavior once, but have not attempted more tests yet. Briefly: Let's assume a simple 2-Drive SATA over USB 3.0 pool with 2-copy duplication -- therefore, each disk should contain a full copy of every file. I pull one disk out (attempting to do so using a USB eject first, but likely to say "in-use"). At that point, I was able to continue to read the pool drive, but unable to write. So... Is this behavior normal for Drive Pool? i.e., when the pool is degraded, is write activity disabled? Why? Isn't a major feature of redundancy (duplication) that the Pool Drive continues to operate normally with no interruption to the applications using the Pool for read and write operations? Thanks for your assistance! ...Terry.
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