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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) ?

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up vote 1 down vote accepted

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


[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                                                                 
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
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Only the mount point and options are displayed in both cases. – eugene y Apr 1 '10 at 9:08
The options should include the directories mounted. It works for me: none /etc unionfs rw,relatime,dirs=/rw/etc=rw:/rootfs_ro/etc=ro 0 0 ('Unionfs 2.5.3 (for 2.6.31)') What UnionFS version do you use? – Jacek Konieczny Apr 1 '10 at 11:55
unionfs-fuse version: 0.21 – eugene y Apr 6 '10 at 13:10
Then it is quite a different thing. – Jacek Konieczny Apr 6 '10 at 17:03
This worked, thanks. – eugene y Apr 6 '10 at 20:52

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