>> Another mystery. >> I copied the file to USB 1TB sandisk. >> md5sum check OK same as my computer >> >> >> md5sum >> /run/media/joseph/SSD-1TB/business/backup/VDI/windows-7_pro_May-23-21.ova >> 6f3348f1fb915af9c45806d947558a37 >> /run/media/joseph/SSD-1TB/business/backup/VDI/windows-7_pro_May-23-21.ova >> >> I mount the same USB 1TB sandisk on another computer and running md5sum on >> same file gives me different number, why??? >> >> md5sum /run/media/fd/SSD-1TB/business/backup/VDI/windows-7_pro_May-23-21.ova >> c478cb48e2f7961cb0e3eb452df6e642 >> /run/media/fd/SSD-1TB/business/backup/VDI/windows-7_pro_May-23-21.ova >> > Did you sync and unmount the partition before ejecting the drive from > the first computer? With a file this large being copied, it is likely > that a large amount of data remains buffered/cached and will not be > fully written to the flash memory even after the copy command completes. > > On the first machine, you would still see the correct md5sum because the > kernel abstracts this fact away from you. But if you rip out the drive > and take it somewhere else without flushing those caches, you're going > to get an incomplete file. > > Check if the file on the drive still md5sums the same if you plug it > back into the first machine. Check what size it is, and whether there > are a lot of 0s at the end indicating an unfinished write. > > cal
Yes, I unmounted the USB device every time. And yes, I plug the USB device back to original machine and md5sum is correct, same as the original. I copied the large file over network to another box and md5sum of: windows-7_pro_May-23-21.ova is correct same as on the original box. I run this: "rsync -avh [source] [destination] && rsync -avhc [source] [destination]" above code rsync files folder on first run and if complete without issue, will run rsync again immediately while performing same file name comparison by using hash of entire file. This i what I got: rsync -avh windows-7_pro_May-29-21.ova fd@10.0.0.138:/home/fd/business/VDI/ && rsync -avhc windows-7_pro_May-29-21.ova fd@10.0.0.138:/home/fd/business/VDI/ sending incremental file list windows-7_pro_May-29-21.ova sent 30.29G bytes received 35 bytes 115.81M bytes/sec total size is 30.28G speedup is 1.00 sending incremental file list windows-7_pro_May-29-21.ova WARNING: windows-7_pro_May-29-21.ova failed verification -- update discarded (will try again). windows-7_pro_May-29-21.ova ERROR: windows-7_pro_May-29-21.ova failed verification -- update discarded. sent 33.44M bytes received 6.47M bytes 123.38K bytes/sec total size is 30.28G speedup is 758.62 rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1330) [sender=3.2.3]
