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<div dir="auto">The procedure outlined should at least get you back to a state where the lv is consistent but with blank sectors where the data is missing. I would suggest using dd to make a backup partition image. Then you can either work on that or the original to mend the fs.</div><div dir='auto'><br></div>
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<div dir="auto">On 27 July 2022 11:50:07 Roger Heflin <rogerheflin@gmail.com> wrote:</div>
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<div dir="auto">I don't believe that is going to work.</div>
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<div dir="auto">His issue is that the filesystem is refusing to work because of the</div>
<div dir="auto">missing data.</div>
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<div dir="auto">man debugfs</div>
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<div dir="auto">It will let you manually look at the metadata and structures of the</div>
<div dir="auto">ext2/3/4 fs. You will likely need to use the "-c" option.</div>
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<div dir="auto">It will be very manual and you should probably read up on the fs</div>
<div dir="auto">structure a bit.</div>
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<div dir="auto">A data recovery company could get most of the data back, but they</div>
<div dir="auto">charge 5k-10k per TB, so likely close to 100k US$.</div>
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<div dir="auto">And the issues will be that 1/3 of the metadata was on the missing</div>
<div dir="auto">disk, and some of the data was on the missing disk.</div>
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<div dir="auto">I was able to do debugfs /dev/sda2 (my /boot) and do an ls and list</div>
<div dir="auto">out the files and then do a dump <filename> /tmp/junk.out and copy out</div>
<div dir="auto">that file.</div>
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<div dir="auto">So the issue will be writing up a script to do lses and find all of</div>
<div dir="auto">the files and dump all of the files to someplace else.</div>
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<div dir="auto">On Wed, Jul 27, 2022 at 2:39 AM Roger James <roger@beardandsandals.co.uk> wrote:</div>
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<div dir="auto">Try https://www.linuxsysadmins.com/recover-a-deleted-physical-volume/?amp</div>
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<div dir="auto">On 26 July 2022 09:16:32 Ken Bass <daytooner@gmail.com> wrote:</div>
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<div dir="auto">(fwiw: I am new to this list, so please bear with me.)</div>
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<div dir="auto">Background: I have a very large (20TB) logical volume consisting of 3 drives. One of those drives unexpectedloy died (isn't that always the case :-)). The drive that failed happened to be the last PV. So I am assuming that there is still 2/3 of the data still intact and, to some extent, recoverable. Although, apparently the ext4 fs is not recognised.</div>
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<div dir="auto">I activated the LV partially (via -P). But running any utility on that (eg: dumpe2fs, e2fsck, ...) I get many of these in dmesg:</div>
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<div dir="auto">"Buffer I/O error on dev dm-0, logical block xxxxxxx, async page read." The thing is, the xxxxxxx block is on the missing drive/pv.</div>
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<div dir="auto">I have also tried some recovery software, but eventually get these same messages, and the data recovered is not really useful.</div>
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<div dir="auto">Please help! How can I get passed that dmesg error, and move on. 14TB recovered is better than 0.</div>
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<div dir="auto">TIA</div>
<div dir="auto">ken</div>
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<div dir="auto">_______________________________________________</div>
<div dir="auto">linux-lvm mailing list</div>
<div dir="auto">linux-lvm@redhat.com</div>
<div dir="auto">https://listman.redhat.com/mailman/listinfo/linux-lvm</div>
<div dir="auto">read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/</div>
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<div dir="auto">_______________________________________________</div>
<div dir="auto">linux-lvm mailing list</div>
<div dir="auto">linux-lvm@redhat.com</div>
<div dir="auto">https://listman.redhat.com/mailman/listinfo/linux-lvm</div>
<div dir="auto">read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/</div>
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<div dir="auto"><br></div>
<div dir="auto">_______________________________________________</div>
<div dir="auto">linux-lvm mailing list</div>
<div dir="auto">linux-lvm@redhat.com</div>
<div dir="auto">https://listman.redhat.com/mailman/listinfo/linux-lvm</div>
<div dir="auto">read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/</div>
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