[dm-devel] device mapper mapping across reboot

[Zdenek Kabelac]

Dne 9.3.2018 v 10:58 jitendra kumar khasdev napsal(a):
> Hi All,
> 
> I wrote the basic target using device mapper framework. Using dmsetup utility 
> I am able to create device node under /dev/mapper/my_custom_mapper.
> 
> But when I do reboot the system, it lost the mapping. Is there any way by 
> which I can create mapping during boot like LVM does.
> 

Hi

lvm2 is exactly solving this problem as it maintains consistent 'metadata' on 
every device - so upon reboot devices are discovered and from their metadata 
dm tables are actived/restored.

So  are you looking for recreation of all the lvm2 infrastructure for this 
relatively quite complex task ?

Or you just want to 'create' DM after kernel is booted ?

Or you even want to pass 'DM' table line on kernel boot option line - so even 
your boot device is a 'DM' device ?


It's unclear which problem are you actually solving so please be more specific.


Regards

Zdenek