Is it possible to automount local SMB/CIFS share from /etc/fstab?

Question

I have Ubuntu 16.04 LTS server with configured public share on it.
My /etc/samba/smb.conf is below

[public_share]
    comment = Ubuntu Public Share
    path = /srv/samba/public_share
    guest ok = yes
    read only = no

For some reasons I need to mount this share on boot to /media/public_share. So I added it to the /etc/fstab:

# <file system> <mount point>   <type>  <options>       <dump>  <pass>
//localhost/public_share /media/public_share/ cifs guest,noperm 0 2

But it does not get mounted on boot. It mounts only manually with sudo mount -a after login.

Adding it to /etc/rc.local such as

mount -t cifs //localhost/public_share /media/public_share/ -o guest,noperm

does not help too.

What am I doing wrong?
How I can auto-mount //localhost/public_share to /media/public_share/ during boot?
Do I need special systemd configuration or something special?

Update 1: For localhost server name I have the following log:

$ systemctl status media-public_share.mount 
● media-public_share.mount - /media/public_share
   Loaded: loaded (/etc/fstab; bad; vendor preset: enabled)
   Active: failed (Result: exit-code) since Вт 2017-12-19 22:15:05 MSK; 16min ago
    Where: /media/public_share
     What: //localhost/public_share
     Docs: man:fstab(5)
           man:systemd-fstab-generator(8)
  Process: 1461 ExecMount=/bin/mount //localhost/public_share /media/public_share -t cifs -o guest,noperm (code=exited, status=32)

дек 19 22:15:05 hostname systemd[1]: Mounting /media/public_share...
дек 19 22:15:05 hostname mount[1461]: Unable to find suitable address.
дек 19 22:15:05 hostname systemd[1]: media-public_share.mount: Mount process exited, code=exited status=32
дек 19 22:15:05 hostname systemd[1]: Failed to mount /media/public_share.
дек 19 22:15:05 hostname systemd[1]: media-public_share.mount: Unit entered failed state.

Changing address to 127.0.0.1, or setting 127.0.0.1 with options username=guest,password=,noperm do not remove "Unable to find suitable address" message.

I moved update 2 and update 3 to answer.

Answer 1

Problem may be solved with one of the following solutions:

• Quick dirty hack with /etc/network/if-up.d:

  cat <<EOF | sudo tee /etc/network/if-up.d/zz-mount-all
  #!/bin/sh
  mount -a
  
  EOF
  
  sudo chmod a+x /etc/network/if-up.d/zz-mount-all
  

With this change it mounts normally:

$ systemctl status media-public_share.mount 
● media-public_share.mount - /media/public_share
   Loaded: loaded (/etc/fstab; bad; vendor preset: enabled)
   Active: active (mounted) (Result: exit-code) since Вт 2017-12-19 23:17:34 MSK; 7s ago
    Where: /media/public_share
     What: //127.0.0.1/public_share
     Docs: man:fstab(5)
           man:systemd-fstab-generator(8)
  Process: 1481 ExecMount=/bin/mount //127.0.0.1/public_share /media/public_share -t cifs -o guest,noperm (code=exited, status=32)

It works even with localhost address.

• It works as expected without hacks if I add x-systemd.automount,noauto to /etc/fstab as

   //localhost/public_share /media/public_share/ cifs guest,noperm,x-systemd.automount,noauto 0 255
  

and it creates two systemd units:

$ systemctl status media-public_share.*
● media-public_share.mount - /media/public_share
   Loaded: loaded (/etc/fstab; bad; vendor preset: enabled)
   Active: active (mounted) since Ср 2017-12-20 20:33:10 MSK; 3min 4s ago
    Where: /media/public_share
     What: //localhost/public_share
     Docs: man:fstab(5)
           man:systemd-fstab-generator(8)
  Process: 2461 ExecMount=/bin/mount //localhost/public_share /media/public_share -t cifs -o guest,noperm,x-systemd.automount (code=exited, status=0/SUCCESS)

дек 20 20:33:10 hostname systemd[1]: Mounting /media/public_share...
дек 20 20:33:10 hostname systemd[1]: Mounted /media/public_share.

● media-public_share.automount
   Loaded: loaded (/etc/fstab; bad; vendor preset: enabled)
   Active: active (running) since Ср 2017-12-20 20:33:02 MSK; 3min 12s ago
    Where: /media/public_share
     Docs: man:fstab(5)
           man:systemd-fstab-generator(8)

дек 20 20:33:09 hostname systemd[1]: media-public_share.automount: Got automount request for /media/public_share, triggered by 2456 (pool)
Warning: Journal has been rotated since unit was started. Log output is incomplete or unavail

But this solution adds two share icons to my Caja file-manager window.

So I'll use if-up.d hack.