Comment 5 for bug 1886994

lp:maas-images doesn't modify the SquashFS at all. The SquashFS is mounted with an overlay so the latest kernels are pulled from the archive. The published SquashFS hash matches what CPC publishes.

The installation is performed by Curtin, MAAS generates curtin.cfg and Curtin formats the disk and writes bits to the filesystem. Neither MAAS nor Curtin do anything with /etc/machine-id. As per documentation systemd seems to be doing the right thing.

You could modify the preseed[1] to run systemd-machine-id-setup to generate a random uuid or create a kernel tag[2] to create a static one.

[1] https://maas.io/docs/custom-node-setup-preseed#heading--curtin
[2] https://maas.io/docs/kernel-boot-options#heading--per-node-kernel-boot-options