On boot also a mount -a is done, thus it seeems strange that it does not function then, but it does later. Any error messages in dmesg?
Edit: I assume your system uses a network configuration “traditional with fup”, because when networkmanager is used the network only starts later after login and thus mounting from remote at boot is impossible.
I will check dmesg tomorrow when I am with the machine.
I also think that this (from swerdna’s tutorial) is important :
The option _netdev is always recommended for cifs mounts in fstab. Option _netdev delays mounting until the network has been enabled. _netdev is known to the command “mount” but not to the command “mount.cifs”. Even though mount.cifs doesn’t recognise _netdev, you should include it in your mount command anyway.
I went through step at a time and found that creating the script after.local did the trick. You have to wait a while after boot to try it, (a little beyond the boot sound) - and then it works perfectly.