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To: Amir Goldstein Cc: linux-unionfs@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, 30 Oct 2025 at 17:54, Amir Goldstein wrote: > > On Thu, Oct 30, 2025 at 6:26=E2=80=AFPM Mark Corbin wrote: > > > > Hello > > > > Is it valid/safe to mount an overlayfs mergedir over the lowerdir? > > > > The Yocto/OE mount-copybind script does exactly that: > > > > overlay on /srv type overlay > > (rw,relatime,lowerdir=3D/srv,upperdir=3D/var/volatile/srv,workdir=3D/va= r/vola > > tile/.srv-work) > > > > I wanted to do something similar with a read-only /etc where the > > merged /etc is mounted on /etc, e.g. > > mount -v -t overlay overlay -o > > lowerdir=3D/etc,upperdir=3D/data/etc,workdir=3D/data/etc-work /etc > > > > Any issues or recommendations? > > None that I can think of. > Overlayfs has no problem with that. > It gets a reference to the lowerdir object at mount time *before* > attaching itself to the mount point and that's it. > > Thanks, > Amir. Thanks Amir. --=20 Mark Corbin Senior Software Engineer | lunarenergy.com | LinkedIn | Instagram --=20 C2:Restricted unless otherwise stated. --=20 Lunar Energy Limited is a company registered in England and Wales,=C2=A0 authorised and regulated by the Financial Conduct Authority under reference= =20 number 767876. Company registration number: 05631091. Registered office: 55= =20 Baker Street, London, England, W1U 7EU