hi,I found a problem, after install multipass, apt updaate in the docker container, dns resolution will be wrong

[jicvi]

$ apt updaate
Err:1 http://archive.ubuntu.com/ubuntu bionic InRelease Could not resolve 'archive.ubuntu.com'

[Saviq]

Hi @jclivi can you please be a bit more clear about what you're trying to do?

Can you just post the commands you ran before apt update?

Multipass has no relation to docker, nor does it deal in containers…

[jicvi]

@Saviq
Before I installed multipass, there was no error when running apt update in the docker container. After I installed multipass, I run apt update in the docker container. The prompt: Err: 1 http://archive.ubuntu.com/ubuntu bionic InRelease Could not resolve ' archive.ubuntu.com '

[jicvi]

$ sudo apt install -y snapd core
$ sudo snap install core
$ sudo snap install multipass --classic
$ multipass launch -c 2 -m 2G -d 20G -n ubuntu
$ multipass mount /home/jclivi/data ubuntu:/home/ubuntu/data

[Saviq]

@jclivi this is still on Deepin Linux? With the default qemu driver of Multipass? And you run Docker next to it?

Both Multipass and Docker use separate (but similar) network stacks. They should not be influencing one another.

I'm sorry, but it's still unclear to me what "docker container" are you referencing.

[jicvi]

“container” ubuntu 18.04

[jicvi]

yes, Deepin Linux

[Saviq]

@jclivi where is the docker container you're referencing? Do you actually mean a Multipass instance? And there is no Docker (it's a completely different technology) in play here?

[jicvi]

@Saviq
docker and Multipass installed in deepin

[jicvi]

After apt update, I couldn't find the reason. I reinstalled the system. I encountered it twice in the same situation, but still couldn't find a solution.

[Saviq]

OK so let me try and summarize:

• you had Docker installed
• and a "Ubuntu 18.04" Docker container (can you please say how exactly you created it?)
• you installed Multipass
• DNS stopped working inside the Docker container
• Multipass continues to work fine?

Did you try removing Multipass to see if that fixes it? Are new Docker containers affected as well?

Please post the commands you used to install Docker and create the container so we can try and reproduce locally.

[jicvi]

@Saviq
“deepin linux”
"install docker"
$ wget https://download.docker.com/linux/ubuntu/dists/bionic/pool/stable/amd64/containerd.io_1.2.2-3_amd64.deb
$ wget https://download.docker.com/linux/ubuntu/dists/bionic/pool/stable/amd64/docker-ce-cli_18.09.2~3-0~ubuntu-bionic_amd64.deb
$ wget https://download.docker.com/linux/ubuntu/dists/bionic/pool/stable/amd64/docker-ce_18.09.2~3-0~ubuntu-bionic_amd64.deb
$ dpkg -i *.deb
$ sudo usermod -aG docker ${USER}

"docker container"
$ docker pull ubuntu
$ docker run --name=ubuntu18 -it ubuntu:latest /bin/bash
$ apt update

is, ok

“deepin linux”
"install multipass"
$ sudo apt install -y snapd core
$ sudo snap install core
$ sudo snap install multipass --classic
$ multipass launch -c 2 -m 2G -d 20G -n ubuntu
$ multipass mount /home/jclivi/data ubuntu:/home/ubuntu/data
$ reboot

$ docker exec -it ubuntu18 /bin/bash
$ apt update

is, error

[Saviq]

Thanks @jclivi we'll try and repro this.

[jicvi]

$ docker exec -it be805af58e79 /bin/bash
root@be805af58e79:/# uname -a
Linux be805af58e79 4.15.0-30deepin-generic #31 SMP Fri Nov 30 04:29:02 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

[julius-ziegler]

We have an issue that seems clearly related, and reproduction is even more fundamental (no name resolution involved, can't ping an ip address):

sudo docker run -it --rm alpine /bin/sh
/ # ping 1.1.1.1

works fine.

then on host system:
sudo snap install multipass

After that, the ping in the docker container stops working.

This error seems to have popped up relatively recently (ca. last week). We observed it first in a more complicated environment, where docker is used to run some CI, and multipass is run by snapcraft, but what I showed here is the minimal setup to reproduce it.

[Saviq]

This is solved now through #2183

[Saviq]

Duplicate of #2183