Restic fails when backing up sockets or fifos. Maybe it tries to read from, but I just want to back up things properly, so I need to have the socket or fifo backed up. Not its content, of course. How to do?
I am now using restic v0.14.0, don’t remember if was the same version when I started with restic and built up my exclude list.
Hm, I have upgrade to restic 0.15.1 and now I don’t find any problems like described with sockets any more (about Fifos not sure if I still have them after deleting some previously installed packages). Nevertheless it seems that the new version has addressed several issues. Hopefully the restore will work too 
For now I think this topic can be closed, it seems no longer relevant.