mount failed: mkdir: cannot create directory '/mnt/data': File exists

[dionizh]

When stopping a minikube mount process with ctrl+C, then try to remount the same disk again, minikube crashed with the following message:

Mounting host path /mnt/scratch/dzhong/redis into VM as /mnt/data ...
o Mount options:
- Type: 9p
- UID: docker
- GID: docker
- Version: 9p2000.L
- MSize: 262144
- Mode: 755 (-rwxr-xr-x)
- Options: map[]
@ Userspace file server: ufs starting

! mount failed: mkdir: cannot create directory '/mnt/data': File exists
: Process exited with status 1

• Sorry that minikube crashed. If this was unexpected, we would love to hear from you:

• https://github.com/kubernetes/minikube/issues/new

Mount command run is a simple:
minikube mount /mnt/scratch/dzhong/redis:/mnt/data

I have to stop minikube, and start it again, for the mount to work.

Running the latest version of minikube and kubectl on centos7.

thanks
dioni

[RA489]

@dionizh can you paste exact command line used?

[dionizh]

Hi I have given the command line above:
minikube mount /mnt/scratch/dzhong/redis:/mnt/data

[tstromberg]

What version of minikube is this with?

I feel like v1.0.1 should handle this properly by using mkdir -p, but perhaps it isn't in this case. If you run into this, do you mind sharing the output of:

minikube ssh ls -lad /mnt/data
minikube ssh df -k /mnt/data

[dionizh]

It is minikube v1.0.1.
Going to check the output of those when I run into the issue again.

[tstromberg]

I can confirm that this happens in v1.1 if a process is still using the old mountpoint. We should output a clearer error when this occurs.

To reproduce:

• Run minikube mount
• In a minikube ssh session, cd to the mount directory.
• Hit Ctrl-C on the minikube mount process
• Re-run minikube mount and watch it fail.

[dionizh]

Thank you. That does sound like what I did.

[fenglixa]

I reproduced this issue, and I would like to provide a PR to fix this issue.
Append my investigation & solution here:

1. "|| true" is in the umount command. It will lead to "force Unmount" will be never called, should be code error.
2. Current "force Unmount" cannot work if mount point is busy.

After address 1, the message will be more clearer to point the mount point is busy.
Error will be gone for this case if 2 is addressed.

@tstromberg any comments? Thanks a lot!

BR
-Francis

[tstromberg]

Sounds good. I'd be happy to review any PR that makes the failure reason more obvious. It may be possible that we can't make umount -f work, but we can at least do a better job of telling the user why the mount failed.

…

On Wed, May 29, 2019, 11:33 PM Francis ***@***.***> wrote: I reproduced this issue, and I would like to provide a PR to fix this issue. Append my investigation & solution here: 1. "|| true" is in the umount command. It will lead to "force Unmount" will be never called, should be code error. 2. Current "force Unmount" cannot work if mount point is busy. After address 1, the message will be more clearer to point the mount point is busy. Error will be gone for this case if 2 is addressed. @tstromberg <https://github.com/tstromberg> any comments? Thanks a lot! BR -Francis — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#4239?email_source=notifications&email_token=AAAYYMBDATI2ZNOWPHBJFKLPX5YL3A5CNFSM4HMBKY32YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODWRP5QQ#issuecomment-497221314>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAAYYMFUJNLL3M43K2COTF3PX5YL3ANCNFSM4HMBKY3Q> .

[fenglixa]

Thanks @tstromberg PR #4393 wish you could help review, any comments are welcome.

[fenglixa]

This issue could be closed by fixes #4393
/close

[k8s-ci-robot]

@fenglixa: Closing this issue.

In response to this:

This issue could be closed by fixes #4393
/close

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