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Make snapshot of non-busy block device with device mapper in Linux
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| 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 |
Hi Joachim,
thank's a lot, it now works.
Kind regards & seasons greetings, Hans
On 21.12.2022 14:23, Joachim Wagner wrote:
@jowagner commented on this gist.
-------------------------
Thanks for reporting the issue. Trying it with and without mounting the
backing device I get the same error message when the device is mounted,
suggesting that dmsetup create cannot use mounted block devices. "Busy"
probably also applies to other scenarios such as the backing device
being part of an active software RAID. Will update the description.
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Thanks for reporting the issue. Trying it with and without mounting the backing device I get the same error message when the device is mounted, suggesting that
dmsetup createcannot use mounted block devices. "Busy" probably also applies to other scenarios such as the backing device being part of an active software RAID. Will update the description.