Description of problem:

There is no 'easy' way to readout content of ring-buffer
e.g. when user is in dracut - there is no 'dd' command,
and retrieving content of previous metadata for being able to run 'vgcfgrestore' is getting tricky if the root volume with archive is unavailable.

So IMHO easiest would be to extent some lvm2 command to be able to dump content of present metadata in the ring-buffer into a file.

i.e.  --scanbufffer {all|#number}  to read last #number of entries and store them into a file - when a PV is given - list just metadata from this PV, otherwise scan and check all devices for metadata

Something in this direction would be quite useful.

It could be possible paired with 'vgcfgrestore --list' 
as i.e.  'vgcfgrestore --scandisk'

so it may eventually work directly without need of temporary file storage -
i.e. revert back by 'x' metadata from given time as listed....

Version-Release number of selected component (if applicable):
2.02.130

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