Can’t mount shared folder. Protocol error

Discussions related to using VirtualBox on Windows hosts.
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Jean Jacques Linux
Posts: 28
Joined: 24. Feb 2009, 05:59

Can’t mount shared folder. Protocol error

Post by Jean Jacques Linux »

Hi.

Host: WinXP SP3;

Guest: Debian 5.0;

Problem: Can’t mount shared folder. Mount command return protocol error.

What I did:

1. Successfully installed guest additions on Debian;
2. Made shared folder on host system (called “shared_folder”. D:\Virtual Box\shared_folder);
3. Made shared folder on guest system (called “shared_folder” too. /home/<user_name>/shared_folder);
4. Devices ? Shared Folders… ? I added a path to shared folder on my host system and set a folder name to “shared_folder”;
5. In bash I typed: #mount -t vboxsf shared_folder /home/<user_name>/shared_folder;
6. And recieved an error: /sbin/mount.vboxsf: mounting failed with the error: Protocol error.

Questions:

1. Does this feature works?
2. What I do wrong?
3. What is the reason of Protocol error?
4. How can I fix it?

Tnx.

Jean Jacques Linux
Last edited by Jean Jacques Linux on 16. Mar 2009, 20:20, edited 1 time in total.
Perryg
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Joined: 6. Sep 2008, 22:55
Primary OS: Linux other
VBox Version: OSE self-compiled
Guest OSses: *NIX

Re: Can’t mount shared folder. Protocol error

Post by Perryg »

Jean Jacques Linux wrote:Hi.

Host: WinXP SP3;

Guest: Debian 5.0;

Problem: Can’t mount shared folder. Mount command return protocol error.

What I did:

1. Successfully installed guest additions on Debian;
2. Made shared folder on host system (called “shared_folder”);
3. Devices ? Shared Folders… ? I added a permanent folder called “shared_folder”;
4. In bash I typed: #mount -t vboxsf shared_folder /home/<user_name>/shared_folder;
5. And recieved an error: /sbin/mount.vboxsf: mounting failed with the error: Protocol error.

Questions:

1. Does this feature works?
2. What I do wrong?
3. What is the reason of Protocol error?
4. How can I fix it?

Tnx.

Jean Jacques Linux
Did you create the folder "shared_folder" under your home directory?
If not it can not find it. Thus the protocol error.
Jean Jacques Linux
Posts: 28
Joined: 24. Feb 2009, 05:59

Re: Can’t mount shared folder. Protocol error

Post by Jean Jacques Linux »

Yes, I made it. This is not the cause of protocol error. If you doesn’t set a shared folder on guest system, you receive a “no such file or directory” error, not a protocol error.
Last edited by Jean Jacques Linux on 16. Mar 2009, 20:38, edited 1 time in total.
Perryg
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Re: Can’t mount shared folder. Protocol error

Post by Perryg »

Jean Jacques Linux wrote:Yes, I made it. This is not the cause of protocol error.
Then the other thing that I would suggest is to change the name and remount the share.
Try something simple and without special charactors. This sometimes causes this as well as Caps.
Try something like "share" .
Jean Jacques Linux
Posts: 28
Joined: 24. Feb 2009, 05:59

Re: Can’t mount shared folder. Protocol error

Post by Jean Jacques Linux »

I tried it.

1. Made host shared folder: C:\shared;
2. Made guest shared folder: /home/<user_name>/shared;
3. Add shared folder C:\shared, folder name: shared;
4. #mount -t vboxsf shared /home/<user_name>/shared;
5. Protocol error.

Doesn’t work.
Perryg
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Posts: 34369
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Re: Can’t mount shared folder. Protocol error

Post by Perryg »

Jean Jacques Linux wrote:I tried it.

1. Made host shared folder: C:\shared;
2. Made guest shared folder: /home/<user_name>/shared;
3. Add shared folder C:\shared, folder name: shared;
4. #mount -t vboxsf shared /home/<user_name>/shared;
5. Protocol error.

Doesn’t work.
From what I see it should work. Permissions may need to be checked on the linux shared folder.

You might try just to see that it is not a selinux thing, is to create the shared folder as root in the /mnt directory.
Then see if you can mount to that one. If so then it may be strickly permissions.

These are the only thing that I have seen to cause the protocol error in Linux with VBox.
Jean Jacques Linux
Posts: 28
Joined: 24. Feb 2009, 05:59

Re: Can’t mount shared folder. Protocol error

Post by Jean Jacques Linux »

Works!

Again, what I did:

1. Made shared folder on host system, D:\Virtual Box\shared;
2. Ran VirtualBox;
3. Ran virtual machine;
4. Linux finished booting, I logged in;
5. I added shared folder D:\Virtual Box\shared, named it “shared”;
6. I made guest shared folder being logged as a user, called it “shared_folder”. /home/<user_name>/shared_folder;
7. $su;
8. Being logged as a root I mounted the shared folder: #mount -t vboxsf shared /home/<user_name>/shared_folder;
9. And all began to work.

May be the problem was host and guest folders had the same names?

Anyway thx for hints, Perryg.
destroyedlolo
Posts: 16
Joined: 11. Mar 2009, 19:01

Re: Can’t mount shared folder. Protocol error

Post by destroyedlolo »

I have the same problem and it happen randomly : try to reboot your PC and you WM to see if it's still working.

In my case, it's working once on 3 or 5 tries :evil:
leManu
Posts: 1
Joined: 17. May 2009, 22:03
Primary OS: MS Windows Vista
VBox Version: PUEL
Guest OSses: Ubuntu Linux

Re: Can’t mount shared folder. Protocol error

Post by leManu »

Try to mount using the following command :

Code: Select all

$ sudo mount.vboxsf share mount_point 
It works right for me (I'm running Ubuntu Linux 9.04 as guest under Vista)
baf
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Re: Can’t mount shared folder. Protocol error

Post by baf »

This is a problem with mount if the share is named the same as a folder where you are standing then you get that error.
Rename the share to something different.
Some say: "You learn as long as you live".
My way: "You live as long as you learn".
Sasquatch
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Re: Can’t mount shared folder. Protocol error

Post by Sasquatch »

This issue is handled in my Shared Folders howto in the Linux Guests forum. http://forums.virtualbox.org/viewtopic.php?f=3&t=15868

Closed. People should have read the VirtualBox FAQ, where the howto is linked to.
Read the Forum Posting Guide before opening a topic.
VirtualBox FAQ: Check this before asking questions.
Online User Manual: A must read if you want to know what we're talking about.
Howto: Install Linux Guest Additions
Howto: Use Shared Folders on Linux Guest
See the Tutorials and FAQ section at the top of the Forum for more guides.
Try searching the forums first with Google and add the site filter for this forum.
E.g. install guest additions site:forums.virtualbox.org

Retired from this Forum since OSSO introduction.
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