How can I list directories that are used by unionfs?

Question

On a debian server, I have unionfs mounted with no entry in fstab. How can I figure out the command, that was used to mount it (or which directories make up the union) ?

Answer 1

Look into /proc/mounts. In many cases /etc/mtab will also contain this information.

Edit: The above will work for unionfs, the 'original one', implemented as kernel module. As you are using the user-space alternative – unionfs-fuse, things are a bit different.

In this case try looking for unionfs-fuse command line:

ps -wfC unionfs-fuse

Example:

[root@lolek ~]# unionfs-fuse -o cow -o allow_other -o use_ino -o nonempty /tmp/a=RW:/tmp/b=RO /tmp/c 
[root@lolek ~]# ps -wfC unionfs-fuse                                                                 
UID        PID  PPID  C STIME TTY          TIME CMD
root      3943     1  0 19:08 ?        00:00:00 unionfs-fuse -o cow -o allow_other -o use_ino -o nonempty /tmp/a=RW:/tmp/b=RO /tmp/c