I have instances for different purposes (asterisk/hostapd/samba etc) .
Any change in rootfs (e.g. apt update/upgrade, fail2ban updates) should be visible in the instances.
In lxc , I can use lxc-clone and provide a configuration like
lxc.rootfs = overlayfs:/var/lib/lxc/lxctest/rootfs:/var/lib/lxc/snapclone/delta0
How can I make my instances inherit/sharing the same rootfs without copying/extracting a new rootfs?