On Wed, Sep 7, 2011 at 11:30 AM, <[1]sf...@users.sourceforge.net> wrote:

     Sam Liddicott:

   > With unionfs-fuse I had my read only tree in two parts, one was a complete
   > chrootable root build environment filesystem, and one was project build
   > sources. Both have different origins and aren't easily combined. The
   project
   > sources need splicing into a subdirectory of the build environment

   ...

     For two RO mounts, you need two RW dirs and two aufs mounts.
     For instance,
     # mount -t aufs -o br:/rw1:/ro1 /aufs
     # mount -t aufs -o br:/rw2:/ro2 /aufs/sub-aufs
     As you wrote, aufs doesn't follow-down the sub-mounts in the branch
     which is a "bind" behaviour instead of "rbind". It is a specification of
     aufs.

   Thanks for the quick answer. I see that this makes sense, but I want to have
   a single cow for my composed chroot file system.
   I have found a way around the problem which perhaps you will patch now I
   tell you :-)
   Having composed my read-only root file system using bind-mounts I can then
   make yet another directory onto which I rbind mount my composed root.
   I then mount that with aufs.
   because aufs doesn't scrutinise such mount paths deeply this works nicely,
   at the cost of an extra directory. It also keeps my chrootly script having a
   similar form whether it uses aufs or falls back to unionfs.
   Thanks for your work on aufs, I appreciate it.

   Sam

References

   1. mailto:sf...@users.sourceforge.net
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