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On 5/29/21 1:32 PM, thelma@×××××××××××.com wrote: |
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> On 5/29/21 2:00 PM, Mark Knecht wrote: |
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>> |
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>> |
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>> On Sat, May 29, 2021 at 12:54 PM <thelma@×××××××××××.com <mailto:thelma@×××××××××××.com>> wrote: |
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>>> |
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>>> I use "scp" to copy large file over local network, windows-7_pro.ova (about 28GB) but I it failed to import the appliance with VirtualBox. |
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>>> Checking the md5sum of the source and destination it turn out they are different. |
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>>> |
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>>> Is "scp" reliable for large files? |
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>> |
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>> In my experience scp is reliable but for large files I'd probably opt for some version of rsync, possibly the -P option. That way if the transfer stops for some reason you can generally pick up where it left off. |
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>> |
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>> HTH, |
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>> Mark |
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> |
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> Another mystery. |
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> I copied the file to USB 1TB sandisk. |
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> md5sum check OK same as my computer |
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> |
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> |
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> md5sum /run/media/joseph/SSD-1TB/business/backup/VDI/windows-7_pro_May-23-21.ova |
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> 6f3348f1fb915af9c45806d947558a37 /run/media/joseph/SSD-1TB/business/backup/VDI/windows-7_pro_May-23-21.ova |
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> |
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> I mount the same USB 1TB sandisk on another computer and running md5sum on same file gives me different number, why??? |
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> |
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> md5sum /run/media/fd/SSD-1TB/business/backup/VDI/windows-7_pro_May-23-21.ova |
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> c478cb48e2f7961cb0e3eb452df6e642 /run/media/fd/SSD-1TB/business/backup/VDI/windows-7_pro_May-23-21.ova |
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> |
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Did you sync and unmount the partition before ejecting the drive from |
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the first computer? With a file this large being copied, it is likely |
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that a large amount of data remains buffered/cached and will not be |
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fully written to the flash memory even after the copy command completes. |
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|
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On the first machine, you would still see the correct md5sum because the |
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kernel abstracts this fact away from you. But if you rip out the drive |
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and take it somewhere else without flushing those caches, you're going |
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to get an incomplete file. |
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|
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Check if the file on the drive still md5sums the same if you plug it |
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back into the first machine. Check what size it is, and whether there |
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are a lot of 0s at the end indicating an unfinished write. |
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|
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cal |
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