How to force OS reload of fstab?

I suspect this is caused by systemd’s conversion of /etc/fstab; traditional mount doesn’t remember the contents of /etc/fstab.

To refresh systemd’s view of the world, including changes to /etc/fstab, run

systemctl daemon-reload

To elaborate the answer from @Stephen Kitt: for example I have this entry in /etc/fstab:

vnetsvr-home:/etc/skel   /etc/skel    nfs4   sec=krb5p,noauto,x-systemd.automount,x-systemd.idle-timeout=10min   0   0

and only doing sudo systemctl daemon-reload doesn't reloaded the fstab. I have to do:

rpi ~$ sudo systemctl daemon-reload
rpi ~$ sudo systemctl restart remote-fs.target

To reload an entry to mount a local filesystem you should use:

rpi ~$ sudo systemctl daemon-reload
rpi ~$ sudo systemctl restart local-fs.target

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