nbd errors and /dev/nbd* files.

[Marcus Lively]

Hi,
Hope someone can help me here, I have noticed the following in my log 
files and have done some research but seem to be drawing blanks. the 
messages are as follows:

 kernel: end_request: I/O error, dev nbd104, sector 4294965120
 kernel: nbd104: Request when not-ready
 kernel: end_request: I/O error, dev nbd104, sector 0
 kernel: nbd105: Request when not-ready
 kernel: end_request: I/O error, dev nbd105, sector 4294965120
 kernel: nbd105: Request when not-ready
...
also
 kernel: Buffer I/O error on device nbd16, logical block 2
 kernel: Buffer I/O error on device nbd16, logical block 3
 kernel: Buffer I/O error on device nbd16, logical block 4
 kernel: Buffer I/O error on device nbd16, logical block 5
 kernel: Buffer I/O error on device nbd16, logical block 6
 kernel: Buffer I/O error on device nbd16, logical block 7
...                                                         
There are a number of nbdnnn files in the /dev directory yet I have not 
configured any nbd filesystems, I have checked lvm and there doesn't 
seem to be any logical volumes configured. My question is why are these 
messages appearing in the logs, and how come I seem to have so many nbd 
device files, could I just remove them from /dev.

Thanks  Marcus.