Feature Request: support devicemapper files

[gdevenyi]

I use a multipathd setup where I have 4 paths (and hence 4 "virtual" disks, per real disk)

It would be nice if I could specify dm-NN and get that locate/fault light turned on.

[amarao]

Hello.

That's would be nice, but I have no idea what is your setup. Can you write the code to do it?

... I think, the problem is lack of tests. I wrote it few years before I got myself used to pytest, so without tests it's really hard to add features.