[dm-devel] multibus / failover and EMC CX600

[David Strand]

I have this same -EEXIST problem.

If the /dev/mapper/mpath* device node is mounted with a file sys when
the disk is disconnected, multipath won't give up one of the device
paths (logs "map in use"). If the disk is then reconnected it will get
a new scsi device name. Now multipath is sometimes confused (shows 3
paths, one of which is ####), and sometimes I get the -EEXIST core
dump to go along with it.

I can do the same disconnect / reconnect of the disk all day long, as
long as no file system is mounted on it. Of course, there will pretty
much always be a file system mounted on it so that isn't really a
solution, just a fact.