Sandbox error : permission denied in docker build

Hi, I am new here.
I installed algorand and sandbox on Ubuntu 18.04.4 LTS.
My user is in the “docker” group, so it has all the permissions to run docker.
Running “./sandbox up” I got the following error message:


W: Unable to read /etc/apt/apt.conf.d/01-vendor-ubuntu - open (13: Permission denied)
W: Unable to read /etc/apt/apt.conf.d/01autoremove - open (13: Permission denied)

E: Error reading the CPU table

Any help?
Thanks.

Can you send us more text around the error message?

You may want to write it between triple backquotes ``` and ```.

Here is the complete output of the “./sandbox up” script:

Sending build context to Docker daemon  9.728kB
Step 1/13 : FROM ubuntu:18.04
 ---> c3c304cb4f22
Step 2/13 : ARG channel
 ---> Using cache
 ---> 4fe4845f7814
Step 3/13 : ENV DEBIAN_FRONTEND noninteractive
 ---> Using cache
 ---> b03b3d708879
Step 4/13 : RUN apt-get update && apt-get install -y ca-certificates
 ---> Running in 302b6a7db495
W: Unable to read /etc/apt/apt.conf.d/01-vendor-ubuntu - open (13: Permission denied)
W: Unable to read /etc/apt/apt.conf.d/01autoremove - open (13: Permission denied)
W: Unable to read /etc/apt/apt.conf.d/01autoremove-kernels - open (13: Permission denied)
W: Unable to read /etc/apt/apt.conf.d/70debconf - open (13: Permission denied)
W: Unable to read /etc/apt/apt.conf.d/docker-autoremove-suggests - open (13: Permission denied)
W: Unable to read /etc/apt/apt.conf.d/docker-clean - open (13: Permission denied)
W: Unable to read /etc/apt/apt.conf.d/docker-gzip-indexes - open (13: Permission denied)
W: Unable to read /etc/apt/apt.conf.d/docker-no-languages - open (13: Permission denied)
E: Error reading the CPU table
The command '/bin/sh -c apt-get update && apt-get install -y ca-certificates' returned a non-zero code: 100

Did you install Docker using snap?
It seems this may cause this issue:

If not, what is your exact setup (OS, way of installing Docker, Docker version, …)?

In the past I installed Docker using “snap”.
Now I uninstalled this and reinstalled Docker by static binaries (cfr. https://docs.docker.com/engine/install/binaries/).
Now “./sandbox up” works fine, without any error.
Thanks a lot.