Cannot pull image read udp 0.0.0.0:32893->8.8.8.8:53: i/o timeout

[tbrosillovh]

Hello,
DNS server 8.8.8.8 is blocked from my network:

$ smolvm machine run --net -it --image ubuntu -- /bin/bash
Starting ephemeral machine (vm-65f3a542)...
Pulling image ubuntu... done.                              
Error: agent operation failed: pull image: crane manifest failed: 2026/06/25 05:46:37 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:54831->8.8.8.8:53: i/o timeout
2026/06/25 05:46:57 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:44027->8.8.8.8:53: i/o timeout
2026/06/25 05:47:17 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:41149->8.8.8.8:53: i/o timeout
Error: fetching manifest docker.io/library/ubuntu:latest: Get "https://index.docker.io/v2/": dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:41149->8.8.8.8:53: i/o timeout

How to configure custom DNS servers?
Thanks!

[BinSquare]

@tbrosillovh I will add configurable dns resolvers here, 8.8.8.8 is currently locked as the default DNS server.

In the meantime, you can potentially try out with the alternative networking backend--net-backend virtio-net which uses 1.1.1.1.

[BinSquare]

Implemented support for custom dns: 7755321

Will be in the next release

[BinSquare]

Released in v1.2.5: https://github.com/smol-machines/smolvm/releases/tag/v1.2.5

Use --dns to set custom dns resolver

[tbrosillovh]

Thanks for the quick patch!

$ smolvm --version
smolvm 1.2.5
$ smolvm machine run --net --dns x.x.x.x -it --image ubuntu -- /bin/bash
Starting ephemeral machine (vm-a370df68)...
Pulling image ubuntu... done.                              
Error: agent operation failed: pull image: crane manifest failed: 2026/06/26 08:41:06 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:43250->8.8.8.8:53: i/o timeout
2026/06/26 08:41:26 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:33566->8.8.8.8:53: i/o timeout
2026/06/26 08:41:46 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:52886->8.8.8.8:53: i/o timeout
Error: fetching manifest docker.io/library/ubuntu:latest: Get "https://index.docker.io/v2/": dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:52886->8.8.8.8:53: i/o timeout

Am I missing something?

[BinSquare]

This is another bug, will fix for the ephemeral mode.

Use the persistent mode:

'''smolvm machine create --net --dns --image ubuntu -n tmp
smolvm machine start tmp
smolvm machine exec tmp -- /bin/bash
smolvm machine rm tmp
'''

[tbrosillovh]

Unfortunately same error:

$ smolvm machine create --net --dns x.x.x.x --image ubuntu --name tmp
Created machine: tmp
  CPUs: 4, Memory: 8192 MiB
Use 'smolvm machine start --name tmp' to start the machine
Then use 'smolvm machine exec --name tmp -- <command>' to run commands
$ smolvm machine start --name tmp
Starting machine 'tmp'...
Pulling ubuntu...
Pulling image ubuntu... done.                              
Error: agent operation failed: pull image: crane manifest failed: 2026/06/26 11:44:40 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:38188->8.8.8.8:53: i/o timeout
2026/06/26 11:45:00 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:51294->8.8.8.8:53: i/o timeout
2026/06/26 11:45:20 retrying dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:45043->8.8.8.8:53: i/o timeout
Error: fetching manifest docker.io/library/ubuntu:latest: Get "https://index.docker.io/v2/": dial tcp: lookup index.docker.io on 8.8.8.8:53: read udp 0.0.0.0:45043->8.8.8.8:53: i/o timeout

[BinSquare]

@tbrosillovh please check again on the newest version:

(base) binsquare@MacBook-Pro-8.local:~/Documents/smolvm/examples/demo (binbin-release-1.4.2*) $ smolvm machine create --net --dns 1.1.1.1 --image ubuntu --name tmp

Created machine: tmp
  CPUs: 4, Memory: 8192 MiB

Use 'smolvm machine start --name tmp' to start the machine
Then use 'smolvm machine exec --name tmp -- <command>' to run commands
(base) binsquare@MacBook-Pro-8.local:~/Documents/smolvm/examples/demo (binbin-release-1.4.2*) $ smolvm machine start --name tmp
Starting machine 'tmp'...
Pulling ubuntu...
Pulling image ubuntu...2026-07-04T16:43:06.742830Z  WARN using plaintext password from config — use password_env instead registry=docker.io
Pulling image ubuntu... done.                              ng...
Machine 'tmp' running (PID: 35368)