Poettering: Factory Reset, Stateless Systems, Reproducible Systems & Verifiable Systems

Why would you need /etc? The question was about stateless systems, which by definition do not have local configuration. Also, again by definition, a factory reset wipes out any local configuration.

Still, even in the cases where you do want /etc, you can use native mount units instead of /etc/fstab. It is strictly unnecessary on systemd systems. Just put your mount units in /etc/systemd/system/.

Of course, using /etc/fstab with systemd is perfectly fine... I do so myself. The whole point is that systemd doesn't care about it at all. The helper tool "systemd-fstab-generator" reads it if it exists and creates mount units for you during early boot (under /run/systemd/generator/), but the actual mounting logic in systemd doesn't even know that the file exists.

The same approach is used for other "legacy" configuration files such as /etc/crypttab