Unable to write to bind mount

[spuder]

colima version 0.2.2
git commit: b2c7697bee2d73e995f156fe8e9870eb246c07e6

runtime: docker
client: v20.10.12
server: v20.10.7

uname -a
Darwin <REDACTED> 21.1.0 Darwin Kernel Version 21.1.0: Wed Oct 13 17:33:23 PDT 2021; root:xnu-8019.41.5~1/RELEASE_X86_64 x86_64

When bind mounting a volume on the host, the filesystem is read only despite using docker functionality to allow for writing to the host

Steps to reproduce

Note that :Z is added to the -v parameter.

docker run -v "$(PWD):/output:Z"  bash:latest touch /output/foo.txt
touch: cannot touch '/output/foo.txt': Read-only file system

I've also tried
4. docker run -v "$(PWD)/output:z" bash touch /output/foo.txt
4. docker run -v "$(PWD)/output:rw" bash touch /output/foo.txt
3. docker run --privileged -v "$(PWD):/output:Z" bash touch /output/foo.txt
4. docker run -v "$(PWD)/output:rw" --group-add=dialout bash touch /output/foo.txt
5. sudo docker run -v "$(PWD)/output:rw" --group-add=dialout bash touch /output/foo.txt

With the same error

Files appear to be owned by 502:dialout

docker run -v "$(PWD)/CAD:/output:rw" bash ls -al /output
total 260
-rw-r--r-- 1 502 dialout  50758 Jan  7 02:48 MPB2015 Feet v4.f3d
-rw-r--r-- 1 502 dialout 212684 Jan  7 02:42 MPB2015-Feet.stl

Is this a known limitation? A bug? Or a misconfiguration on my part? Any guidance appreciated.

[spuder]

I suspect this is a lima problem

lima-vm/lima#34 (comment)

Looking at ~/.lima/default/lima.yaml` the default settings are:

# Expose host directories to the guest, the mount point might be accessible from all UIDs in the guest
# Default: none
mounts:
  - location: "~"
    # CAUTION: `writable` SHOULD be false for the home directory.
    # Setting `writable` to true is possible, but untested and dangerous.
    writable: false
  - location: "/tmp/lima"
    writable: true

I don't know if this quite translates to the problem that I am seeing, but it does seem like a plausible correlation.

[abiosoft]

@spuder version 0.2.2 do not mount home directory as writeable by default, kindly install the latest development version with brew install --head colima.

[spuder]

colima stop
colima delete
brew unlink colima
brew install --head colima
colima start

While I no longer get the error Read-only file system, I'm finding that I'm unable to write to the host

docker run -v "$(PWD):/output" bash ls /output
docker run -v "$(PWD):/output" bash touch /output/foo.txt
ls | grep foo.txt 
# no results

[spuder]

I've uncovered some sort of race condition, because I'm now able to touch a file once, but if I delete the file and try again I always get an error

❌

rm foo.txt
docker run -v "$(PWD):/output" bash touch "/output/foo.txt"
ls | grep foo.txt
foo.txt <------ notice that file exists 
rm foo.txt
docker run -v "$(PWD):/output" bash touch "/output/foo.txt"
touch: /output/foo.txt: No such file or directory

Does lima\colima sync the file system periodically? I find that If I put a sleep between the touch statements, eventually I get to the point where it can write to the volume consistently

If I write a file with a unique name, it always works

✅

docker run --rm -v "$(PWD):/output" bash touch "/output/$(date).txt"
docker run --rm -v "$(PWD):/output" bash touch "/output/$(date).txt"
ls 
Mon Jan 10 16:22:33 MST 2022.txt   Mon Jan 10 16:22:40 MST 2022.txt

It seems like when you create/delete a file with lima/colima it is caching that file for a few seconds so you can't immediately write a file with the same name.

[jphenow]

This is sounding similar #65 maybe? I'm experiencing things more like #65 but the two sound very similar.

[jphenow]

I've been tinkering with stuff around this issue to see if I can get any better results but have been as yet unsuccessful

[yinshangwei]

When mounting Postgres data, they will be an error. Seems like the same issue.
chown: changing ownership of '/var/lib/postgresql/data': Permission denied

[vraravam]

Yes - I too have the same issue with the following docker-compose.yml file:

version: '3'
services:
  db:
    image: "postgres:13.4"
    container_name: api-db
    volumes:
      - ./postgres-data:/var/lib/postgresql/data:Z
    environment:
      - POSTGRES_USER=apiDbUser
      - POSTGRES_PASSWORD=apiDbPassword
      - POSTGRES_DB=apiDb
    ports:
      - "5433:5432"

I'm using the latest HEAD version of colima along with the above.

[abiosoft]

@spuder kindly update colima and lima and try again.

brew upgrade lima colima

[spuder]

I just upgraded colima and lima, but I"m not seeing that bind mounts don't work at all

brew upgrade lima colima
colima version 
  colima version 0.3.1
  git commit: 787ae5631ae8de072feef95a509c47fc93308b2e
  
  runtime: docker
  arch: x86_64
  client: v20.10.12
  server: v20.10.11
colima stop
colima delete
colima start
docker run -v "$(PWD):/output" bash touch "/output/foo.txt"
ls | wc -l
0 <-------------- This should say 1 because there should be 1 file named foo.txt in the directory

I've reproduced this twice now and I'm pretty sure this is a regression

[john-ot]

I'm able to reproduce the issue as well. I'm running:
colima start --cpu 2 --memory 8 --disk 40 --mount $HOME/IdeaProjects:/IdeaProjects:rw

But when I look at ~/.lima/colima/lima.yaml I see this:

mounts:
    - location: /Users/john/Library/Caches/colima
      writable: false
    - location: /Users/john/IdeaProjects/
      writable: false

I'm running colima 0.3.2

[abiosoft]

I'm able to reproduce the issue as well. I'm running: colima start --cpu 2 --memory 8 --disk 40 --mount $HOME/IdeaProjects:/IdeaProjects:rw

@john-ot You do not need to specify the mount actually, your $HOME directory is mounted by default, get rid of the mount flag and try again, you should not have any problems.
Nonetheless, your mount syntax is wrong, it should be --mount $HOME/IdeaProjects:w.

[john-ot]

Ack! I will fix the syntax.

Does the default mount give me write access though? I thought it was read only by default?