Mounting Filesystem over existing directory

[Bartos-Elekes Zsolt]

Michael Conrad wrote:

> Unionfs has one problem though: the only way to get correct behavior is 
> to merge path A and B onto mountpoint C.  (C can't be the same as A or B).

Perhaps this is valid only for older versions of unionfs. I am using unionfs 
mounted on /var that is composed of a tmpfs mounted on /mnt/tmpfs, and the 
original /var that is on the flash (containing only a few important files and 
directories that must be preserved across reboots, like /var/lib/dpkg).

$ mount | grep "unionfs"
unionfs on /var type unionfs (rw,relatime,dirs=/mnt/tmpfs=rw:/var=rw)

-- 
Zsolt