Why I did it
The current lazy installer relies on a filename sort for both unpack and configuration steps. When systemd services are configured [started] by multiple packages the order is by filename not by the declared package dependencies. This can cause the start order of services to differ between first-boot and subsequent boots. Declared systemd service dependencies further exacerbate the issue (e.g. blocking the first-boot script).
The current installer leaves packages un-configured if the package dependency order does not match the filename order.
This also fixes a trivial bug in [Build]: Support to use symbol links for lazy installation targets to reduce the image size #10923 where externally downloaded dependencies are duplicated across lazy package device directories.
How I did it
Changed the staging and first-boot scripts to use apt-get:
dpkg -i /host/image-$SONIC_VERSION/platform/$platform/*.deb
becomes
apt-get -y install /host/image-$SONIC_VERSION/platform/$platform/*.deb
when dependencies are detected during image staging.
How to verify it
Apt-get critical rules
Add a Depends= to the control information of a package. Grep the syslog for rc.local between images and observe the configuration order of packages change.