Docker shared folders on a Mac :(

Docker Desktop for Mac
1

I’m using the docker builder on packer and having an issue. I’m posting here (as well as the packer forums) because it looks to be more of a docker issue than a packer issue.

When I run the packer docker builder, packer is running the following docker command:

docker run -v /var/folders/j4/nqyjdv994637sq_l7_d9465h0000gn/T/packer-docker426021951:/packer-files -d -i -t ubuntu /bin/bash

Docker then fails with the following error:

Build ‘docker’ errored: Error running container: Docker exited with a non-zero exit status.
Stderr: docker: Error response from daemon: Mounts denied: -for-mac/osxfs/#namespaces for more info.
.
sq_l7_d9465h0000gn/T/packer-docker426021951
is not shared from OS X and is not known to Docker.
You can configure shared paths from Docker → Preferences… → File Sharing.
See https://docs.docker.com/docker.

I have Mac OS version 10.11.5, docker version ‘1.12.5, build 7392c3b’ and packer version 0.12.1. I have shared the /var/folders directory in docker (which it translates to /private). After hours of googling it seems I am the only person in the universe having this issue. For what its worth, the packer config is the most simple possible, simply:

{
  "builders": [
    {
      "type": "docker",
      "image": "ubuntu",
      "export_path": "image.tar"
    }
  ]
}

I’m using docker for other things (chef and test kitchen and the test kitchen docker driver) and they work fine.

2

The issue looks to be your path to your mac folder is being truncated at the first space spaces need to be marked with a \ for example a directory called /January 2017 on your mac would be referenced in the command as /January\ 2017/

hope this helps

3

Sorry, where’s the space?

4

Hmmm should have zoomed in they are under scores…LOL sorry,

I do see one thing is /packer-files the directory on your mac?

5

The reason I ask is the error is due to not finding sq_l7_d9465h0000gn/T/packer-docker426021951 on the host you are deploying the container to…

6

the syntax is /HOST-DIR:/CONTAINER-DIR

if this model is being followed correctly then you need to look at whether docker preferences > filesharing has access to the folder you want to map in the container.

7

Yes, file sharing has access to /private. I added /var/folders to sharing but it changed it to /private.

8

Under /private is the path displayed like /private/var/log/ ?

If not there is something wrong with mapping the path you provided docker…
maybe a permission issue…?

I am guessing at this point… I had no problem adding a directory and mapping that path.

9

Here’s what I got:

doug@ip-10-0-0-44 slice-motd (dev) (master)*$ ls -l /private
total 0
drwxr-xr-x  95 root  wheel  3230 Dec 21 23:12 etc
drwxr-xr-x   2 root  wheel    68 Aug  1  2015 tftpboot
drwxrwxrwt  39 root  wheel  1326 Jan 10 08:02 tmp
drwxr-xr-x  24 root  wheel   816 Jun 27  2016 var

doug@ip-10-0-0-44 slice-motd (dev) (master)*$ ls -l /private/var
total 0
drwx------    2 root       wheel         68 Mar 13  2016 agentx
drwxr-xr-x    8 daemon     wheel        272 May  4  2016 at
drwx------  611 root       wheel      20774 Jan  4 15:22 audit
drwx------    2 root       wheel         68 Feb 25  2016 backups
drwxr-xr-x   68 root       wheel       2312 Jan  9 21:03 db
drwxr-xr-x    2 root       sys           68 Feb 25  2016 empty
drwxrwxrwx    5 root       wheel        170 Aug  9 11:26 folders
drwxr-x---    2 _jabber    _jabber       68 Aug  1  2015 jabberd
drwxr-xr-x    3 root       wheel        102 Aug  1  2015 lib
drwxr-xr-x   79 root       wheel       2686 Jan 10 07:20 log
drwxrwxr-x    2 root       mail          68 Feb 25  2016 mail
drwxr-xr-x    3 root       wheel        102 Feb 25  2016 msgs
drwxr-xr-x    2 root       wheel         68 Feb 25  2016 netboot
drwxr-xr-x    5 _networkd  _networkd    170 Jun 27  2016 networkd
drwxr-x---    8 root       wheel        272 Dec 13 11:39 root
drwxr-xr-x    4 root       wheel        136 Jun 27  2016 rpc
drwxrwxr-x   33 root       daemon      1122 Jan 10 07:43 run
drwxr-xr-x    2 daemon     wheel         68 Feb 25  2016 rwho
drwxr-xr-x    7 root       wheel        238 May  4  2016 spool
drwxrwxrwt   15 root       wheel        510 Jan 10 08:38 tmp
drwxr-xr-x    3 root       wheel        102 Jan  9 13:22 vm
drwxr-xr-x    4 root       wheel        136 Jun 27  2016 yp

doug@ip-10-0-0-44 slice-motd (dev) (master)*$ ls -ld /private/var/log
drwxr-xr-x  79 root  wheel  2686 Jan 10 07:20 /private/var/log
10

Someone who understands how the Docker App works might need to jump in.
if you run PS -Ajcf | grep docker you will see docker is running under your UID I am not seeing your issues but I have my Mac user ID as part of the Wheel group which is why I have no issues i think

this is not an MacOS default for a user so you may need to change that to resolve the issues with access to VAR…

This is a guess on my part so you may want to get another opinion. But I have verified my user is part of group wheel so I have the permissions I need and so does the docker process running under my ID.

11

I see you have given others RWX did you do this recursively? chmod -R?

12

The only other thing I see is the docker command is missing some variables usually needed but this should be spinning a different error…

this is how a docker command should look

docker run -it --name ‘containername’ -v /host folder:container folder -p ‘port number to advertise’:‘port number inside container’ -d ‘image name’

an example:
docker run -it --name dba1 -v /media/data:/var/lib/mysql/ -p 3306:3306 -d db1

13

Sorry I could not be of more help :worried:

14

@dgarstang The path /var/folders/j4/nqyjdv994637sq_l7_d9465h0000gn/T/packer-docker426021951 isn’t shared from OS X and doesn’t exist in the VM. If it exists in OS X, you could try using /private/var/folders/j4/nqyjdv994637sq_l7_d9465h0000gn/T/packer-docker426021951 or you could edit the OS X directories exported in the File Sharing preferences panel by highlighting /private/var/folders and then clicking again to edit the path and change it to /var/folders.

15

Look out this solution. I was having the same problem:

16

I have the same problem. Docker desktop for Mac (latest stable) won’t accept ‘/var/lib’ as a path.

When I try ‘docker-compose up’ I get errors like this:
ERROR: for mysql Cannot create container for service mysql: invalid mount config for type “bind”: bind source path does not exist: /var/lib/mydata/mysqldata

17

Well, I reinstalled docker desktop for Mac, restarted my Mac, cleaned out the app’s data with “Clean / Purge data”, and the above problem is gone. However, I’m now seeing:

ERROR: for livy Cannot start service livy: path /host_mnt/Users/gordonl/n/COMBINEPROJECT/combine-docker/combine/combine is mounted on /host_mnt but it is not a shared mount

I’m confused about how to fix this:
System Preferences?
Command line?
Docker Desktop?

Any help would be appreciated since I’ve been trying to resolve this for a week.

18

macOS Catalina v10.15.6
iMac (Retina 5K, 27-inch, 2019)

Docker Desktop v2.4.0.0

⇒ docker info
Client:
Debug Mode: false

Server:
Containers: 12
Running: 5
Paused: 0
Stopped: 7
Images: 75
Server Version: 19.03.13
Storage Driver: overlay2
Backing Filesystem: extfs
Supports d_type: true
Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host ipvlan macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 8fba4e9a7d01810a393d5d25a3621dc101981175
runc version: dc9208a3303feef5b3839f4323d9beb36df0a9dd
init version: fec3683
Security Options:
seccomp
Profile: default
Kernel Version: 4.19.76-linuxkit
Operating System: Docker Desktop
OSType: linux
Architecture: x86_64
CPUs: 8
Total Memory: 1.944GiB
Name: docker-desktop
ID: 5AO5:QDDP:5K2E:3IU6:4YMW:IXEW:3IOB:J7DP:UU4J:NAS6:RHPV:C4TW
Docker Root Dir: /var/lib/docker
Debug Mode: false
HTTP Proxy: gateway.docker.internal:3128
HTTPS Proxy: gateway.docker.internal:3129
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false
Product License: Community Engine