<div dir="ltr">Sorry to hear about this. UUIDs suck to work with (too long for normal short term memory - too non-associative for long-term memory) but they as certainly stable and definitive.<br></div><div class="gmail_extra">
<br><br><div class="gmail_quote">On Tue, Apr 30, 2013 at 8:42 PM, George Allen <span dir="ltr"><<a href="mailto:glallen01@gmail.com" target="_blank">glallen01@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
So, I just finished recovering from a data-loss causing error in the new ubuntu:<br>
<br>
I had one hard drive with 12.10, and a new one with a fresh install of 13.04.<br>
Both used LVM, with slightly different custom setups...<br>
<br>
In transferring the files from the old to new drives, via rsync and an<br>
external usb adapter, the transfer suddenly errored out after several<br>
GBs.<br>
<br>
I don't have the logs handy to give better notes (specific errors),<br>
but basically:<br>
- sometime late in the rsync the computer decided to write something to swap.<br>
- 13.04 had created the cryptswap device using /dev/dm-3 instead of<br>
/dev/mapper/vg-swap or a UUID (in /etc/crypttab)<br>
- sometime in my modifying the partitions/lvm and adding a usb drive<br>
that also contained lvm volumes, /dev/dm-* were re-numbered<br>
<br>
So as soon as the computer touched swap, it corrupted my /dev/vg/home<br>
logical volume<br>
<br>
It took me a while to figure out what was going on... then with blkid<br>
and lots of googling I managed to find out by comparing UUIDs for each<br>
device.<br>
<br>
To avoid further problems - grep -rE '/dev/(sd.|mapper|disk|dm)' * on<br>
both systems confirmed that '/etc/crypttab' on the 13.04 install was<br>
the only important file that referenced anything by dm-* but that one<br>
file can hose your system if somehow dmsetup renumbers things after<br>
changes.<br>
<br>
-George<br>
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</blockquote></div><br><br clear="all"><br>-- <br>-- <br>James P. Kinney III<br><i><i><i><i><br></i></i></i></i>Every time you stop a school, you will have to build a jail. What you
gain at one end you lose at the other. It's like feeding a dog on his
own tail. It won't fatten the dog.<br>
- Speech 11/23/1900 Mark Twain<br><i><i><i><i><br><a href="http://electjimkinney.org" target="_blank">http://electjimkinney.org</a><br><a href="http://heretothereideas.blogspot.com/" target="_blank">http://heretothereideas.blogspot.com/</a><br>
</i></i></i></i>
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