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@jowagner
Last active January 16, 2023 14:32
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Make snapshot of non-busy block device with device mapper in Linux
NAME=nameofsnapshot
DEVRO=/dev/read-only-backing-device
DEVCOW=/dev/space-for-writing-changes
SECTORS=$(blockdev --getsz $DEVRO)
TABLE=$(mktemp)
echo 0 $SECTORS snapshot $DEVRO $DEVCOW N 16 >> $TABLE
echo "Setting up $NAME with"
head $TABLE
dmsetup create $NAME < $TABLE
rm $TABLE
@hwk
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hwk commented Dec 22, 2022 via email

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