Virtualbox shared folder mount from fstab fails; works once bootup is complete

Question

I've got Ubuntu 13.10 installed in Virtualbox 4.3. The host machine is Windows.

I have a couple of Virtualbox shared folders being mounted by /etc/fstab. Until recently this setup worked just fine, but after upgrading from Ubuntu 13.04 and Virtualbox 4.2 (at essentially the same time) the fstab mounting stopped working. I get the following error during boot:

An error occurred while mounting /home/benme/Documents.
keys:Press S to skip mounting or M for manual recovery

Pressing M for manual recovery and then trying to mount manually also fails:

root@benme-vb:~# cd /home/benme
root@benme-vb:/home/benme# mount Documents
/sbin/mount.vboxsf: mounting failed with the error: No such device

But if I instead skip mounting during boot, wait for Unity to start and then mount manually in a shell, everything works fine:

benme-vb ~ % ls Documents
benme-vb ~ % sudo mount Documents
[sudo] password for benme: 
benme-vb ~ % ls Documents
    # actual file list omitted

Note that when I mount manually I'm letting mount take all the options from /etc/fstab, and it works. This suggests to me that it's some sort of timing issue, where Virtualbox isn't "ready" to provide the shared file mounts at the point /etc/fstab mounts are run during bootup.

Here's the fstab line, just for completeness:

Documents       /home/benme/Documents   vboxsf  uid=benme,gid=benme,dmode=774,fmode=664     0   0

Is there something I can do about this from the Ubuntu side? Or does anyone happen to know more about this from the Virtualbox angle?

I've found an old report on the Virtualbox bug-tracker with identical symptoms, but in that case the user had updated Virtualbox without updating their guest additions and resolving that fixed the problem; this isn't happening here, I've definitely got the 4.3 guest additions installed.

Richard Turner · Accepted Answer · 2014-01-15T14:16:59.760

49

I ran afoul of this problem too. I mount /var/www using VBox shared folders functionality, so this was quite annoying.

The solution I found was to force the vboxsf module to be loaded early, before the mounting of file systems. Just add vboxsf on a line of its own in /etc/modules.

Another solution is to set noauto in /etc/fstab and manually mount drives in /etc/rc.local, but this wasn't such a good solution for me because by that time Apache has already started and been unable to find anything in /var/www.

edited Jan 15 '14 at 14:16

answered Oct 25 '13 at 16:04

Richard Turner

998

1

awesome! adding to /etc/modules worked perfectly. thanks Richard! – ThePosey Feb 11 '14 at 15:53
@ThePosey Glad to have helped! – Richard Turner Feb 12 '14 at 08:46
This was issue for me on Ubuntu Server 14.04 guest. And this answer (the /etc/modules solution) solved it for me. Thanks!
P.S Btw, if you by chance, trying to figure out / fix things, enabled Auto-mount in Virtualbox settings, disable it again ;)
– Reinis Jul 15 '14 at 07:59
What is actual line of code/text that is used with this solution? @Reinis – qodeninja Mar 10 '15 at 01:40
2

@qodeninja As I said in my second paragraph: "Just add vboxsf on a line of its own in /etc/modules. – Richard Turner Mar 10 '15 at 08:53
1

I had to add vboxguest and vboxsf to /etc/modules on a Ubuntu 14.04 guest system for this to work. – mattanja Jun 20 '16 at 19:15

deoren · Answer 2 · 2015-10-19T17:39:00.330

23

In addition to Richard Turner's suggestion of adding vboxsf on a line of its own to /etc/modules, I suggest adding the _netdev mount option to /etc/fstab. I tested on Ubuntu 12.04 LTS and this seems to add just the right amount of delay for the mount to succeed.

My /etc/fstab entry:

dev /media/dev vboxsf defaults,_netdev 0 0

edited Oct 19 '15 at 17:39

answered Oct 19 '14 at 21:38

deoren

373
2
9

4

This works for me, even without using Turner's solution. Make a lot of sense too, since the Ubuntu Community Help page for fstab options says, "_netdev - this is a network device, mount it after bringing up the network." I did not have to load vboxsf in /etc/modules, just adding _netdev worked! – Mark Mikofski Feb 23 '16 at 19:45
1

This works for me too on Ubuntu 16.04, even without Turner's solution. – Zhenya Feb 17 '17 at 09:00

Torben · Answer 3 · 2014-12-22T11:26:28.973

5

Richard's fix stopped working for me after the last update (VirtualBox 4.3.18, Ubuntu 14.04). Luckily I was able to fix it, by loading vboxsf right with the kernel:

# echo "vboxsf" >> /etc/initramfs-tools/modules
# update-initramfs -u

The first command adds a parameter to load the module to the kernel and the second updates the init file system. After a reboot I was able to use my fstab-mounts again :)

Warning: The boot process might freeze, if a shared folder cannot be mounted. So test your configuration, before you add the module to initramfs. If your system hangs anyway, you can boot in recovery mode to fix the problem.

edited Dec 22 '14 at 11:26

answered Oct 20 '14 at 21:03

Torben

271
5
6

I tried this solution to load the vboxsf module earlier ... It just froze my boot sequence so I had to remove it. – Rerito Nov 27 '14 at 09:05
Yeah, including the module that early might freeze the boot process, if your shared folder configuration is broken. However, I never experienced any boot freezes with a correct configuration... – Torben Nov 27 '14 at 12:46
I've added a warning to the answer to make things clearer. – Torben Nov 27 '14 at 12:51

score 4 · Answer 4 · answered May 19 '14 at 15:44

4

I just wanted to say that forcing the vboxsf module to load early helped me (as in Richard Turner's answer), but the fstab line still didn't work for me.

What I ended up doing was putting the mount command (which did work) into /etc/rc.local. A bit of a hack but it worked.

answered May 19 '14 at 15:44

ezuk

141

1

I don't understand how Richard Turner's suggestion "helped you", but at the same time, the fstab line "still didn't work for you"...? – j_random_hacker Apr 12 '17 at 12:44

score 4 · Answer 5 · answered Oct 01 '15 at 10:52

With the shared folder listed in fstab I find that the boot will hang when it tries to mount it using VirtualBox 5 and Ubuntu 14.04. The solution seems to be to delay mounting until the GuestAddition service is available (Richard Turner's /etc/modules solution didn't seem enough for me).

To do this make sure you have noauto as the options for the shared folder in /etc/fstab. For example for a shared folder called vmshare:

vmshare    /home/user/share    vboxsf    defaults,noauto    0    0

Then add a line to /etc/rc.local to mount the share after booting:

mount vmshare

This was the only solution that worked for me, using VBox 5.0.16 and Ubuntu 14.04 — T.J. Compton, Apr 28 '16 at 13:50

score 3 · Answer 6 · answered Jan 27 '20 at 22:24

As per 2020, the only (and clean) working solution for me is the one described in the Arch Wiki as posted by ultracrepidarian. In the meanwhile the entry in the fstab looks slightly different:

desktop  /media/desktop  vboxsf  uid=<user-id>,gid=<group-id>,rw,dmode=700,fmode=600  0  0

score 3 · Answer 7 · answered Jan 17 '17 at 08:25

3

It looks like the vboxsf lacks the fs-vboxsf alias (which is how kernel modules get autoloaded when mounting that filesystem type for the first time), so adding the alias in /etc/modprobe.d should do the trick:

$ echo "alias fs-vboxsf vboxsf" | sudo tee /etc/modprobe.d/vboxsf.conf

answered Jan 17 '17 at 08:25

hyperair

251
2
4

Haven't tried this myself, but it looks promising. – j_random_hacker Apr 12 '17 at 13:11

score 2 · Answer 8 · answered Feb 03 '15 at 00:02

2

I had the same problem, and was working through the suggested solutions, but without success. Torben's solution froze the boot, so had to undo it. Then I thought I should troubleshoot /etc/fstab using sudo mount -a. The syntax of my entry looked perfect, but it still failed. I was also able to manually mount the filesysten using the mount command in the terminal window.

What I found is that I had spaces between the first two parameters (device and mount point). I replaced them with a tab and it works. Really?!!!!

answered Feb 03 '15 at 00:02

svenyonson

121
1

Are you sure it was two space characters (ASCII code 32)? Because one or more of those should be just as fine as a tab character. Sometimes I accidentally type non-breaking space characters when I press my shift key to early or release it too late while pressing the space bar. They look the same but confuse many applications. – David Foerster Feb 03 '15 at 01:10
All I know is that I backspaced over all of the white space and inserted a single tab and it then it worked. – svenyonson Feb 04 '15 at 03:52
Switching my spaces for tabs worked for me. My existing /etc/fstab had spaces in it (as far as I could tell) and I replicated them exactly. The existing lines had a single space. But re-writing mine with tabs got everything working. – jcaruso Nov 28 '15 at 17:53
This didn't work for me, but following Kevin Sadler's recommendation of using noauto to delay mounting then adding mount <sharename> to rc.local did the trick. I did not try Turner's solution. – Mark Mikofski Feb 23 '16 at 19:15

score 1 · Answer 9 · edited Dec 17 '14 at 19:31

1

I believe I've found the right way to deal with this in Arch Wiki. Use comment=systemd.automount option.

The above option goes in the /etc/fstab file with the other options. For example:

Fedora /var/ftp/pub/Fedora vboxsf uid=1001,gid=1001,comment=systemd.automount 0 0

edited Dec 17 '14 at 19:31

guntbert

13,134

answered Nov 17 '14 at 22:21

ultracrepidarian

133

1

This didn't work for me, but Keven Sadlier's answer did. – Mark Mikofski Feb 23 '16 at 19:16

Virtualbox shared folder mount from fstab fails; works once bootup is complete

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