I am using Debian Trixie generic cloud image (debian-13-amd64-20260706-2531.qcow2)
when setting up the basic configuration works, however anything requiring a network
connection, e.g. installing packages, fails with a 'could not resolve' error
when looking up the APT proxy. After the set-up fails I can log in to the VM
and perform an 'apt update' and 'apt upgrade' as normal.
It almost seems like the DNS configuration hasn't been fully applied yet by the time
cloud-init attempts to install packages. Although the logging indicates that the
network target has already been reached.
As this appears to be a timing (race?) issue, I am not sure how to diagnose it
futhter. Any suggestion are most welcome.
More specifically I am running the generic image as a QEMU/KVM VM on a Debian
Bookworm host. I am using the following command to start the VM:
virt-install --name cloudtest --vcpus vcpus=1,maxvcpus=2 --cpu host-passthrough \
--memory currentMemory=1024,memory=2048 --osinfo name=debiantesting --import \
--disk path=/dev/alpha/test-cloud,driver.discard=unmap \
--events on_poweroff=destroy,on_reboot=restart,on_crash=destroy \
--input type=keyboard --input type=mouse --input type=tablet \
--network network=guest,type=bridge,source=guest \
--cloud-init user-data=$(pwd)/user-data,meta-data=$(pwd)/meta-data,network-config=$(pwd)/network-config
The meta-data file is empty. The network-config files contains:
network:
version: 2
ethernets:
net0:
match:
name: enp1s0
dhcp4: false
dhcp6: false
accept-ra: false
link-local: [ipv6]
addresses:
- [redacted].0.130/24
- [redacted]:30::130/64
routes:
- to: default
via: [redacted].0.254
on-link: true
- to: default
via: [redacted]:30::fefe
on-link: true
nameservers:
search: [mydomain.local]
addresses:
- [redacted].0.254
The user-data file contains:
#cloud-config
fqdn: "cloudtest.mydomain.local"
manage_etc_hosts: true
users:
- name: "laurensb"
gecos: "Laurens Blankers"
ssh_authorized_keys:
- "ssh-rsa [redacted]"
sudo: "ALL=(ALL) NOPASSWD:ALL"
shell: "/bin/bash"
final_message: |
cloud-init has finished
version: $version
timestamp: $timestamp
datasource: $datasource
uptime: $uptime
ntp:
enabled: false
package_update: true
package_upgrade: true
package_reboot_if_required: true
packages:
- vim
- rsyslog
timezone: "Europe/Amsterdam"
ssh_pwauth: false
chpasswd:
expire: false
apt:
primary:
- arches: [default]
uri: "http://deb.debian.org/debian"
security:
- arches: [default]
uri: "http://deb.debian.org/debian-security"
http_proxy: "http://updates.mydomain.local:3142/"
ca_certs:
remove_defaults: false
trusted:
- |
[redacted]
write_files:
- path: '/root/.ssh/authorized_keys'
owner: 'root:root'
permissions: '0644'
content: |
ssh-rsa [redacted]
And the relevant parts of /var/log/cloud-init-output.log:
Cloud-init v. 25.1.4 running 'modules:final' at Mon, 13 Jul 2026 07:27:39 +0000. Up 12.34 seconds.
Get:1 file:/etc/apt/mirrors/debian.list Mirrorlist [29 B]
Get:5 file:/etc/apt/mirrors/debian-security.list Mirrorlist [38 B]
Ign:2 http://deb.debian.org/debian trixie InRelease
Ign:3 http://deb.debian.org/debian trixie-updates InRelease
Ign:4 http://deb.debian.org/debian trixie-backports InRelease
Ign:6 http://deb.debian.org/debian-security trixie-security InRelease
Ign:2 http://deb.debian.org/debian trixie InRelease
Ign:2 http://deb.debian.org/debian trixie InRelease
Ign:6 http://deb.debian.org/debian-security trixie-security InRelease
Ign:4 http://deb.debian.org/debian trixie-backports InRelease
Ign:3 http://deb.debian.org/debian trixie-updates InRelease
Err:2 http://deb.debian.org/debian trixie InRelease
Could not resolve 'updates.mydomain.local'
Ign:3 http://deb.debian.org/debian trixie-updates InRelease
Ign:4 http://deb.debian.org/debian trixie-backports InRelease
Ign:6 http://deb.debian.org/debian-security trixie-security InRelease
Err:6 http://deb.debian.org/debian-security trixie-security InRelease
Could not resolve 'updates.mydomain.local'
Err:4 http://deb.debian.org/debian trixie-backports InRelease
Could not resolve 'updates.mydomain.local'
Err:3 http://deb.debian.org/debian trixie-updates InRelease
Could not resolve 'updates.mydomain.local'
Reading package lists...
W: Failed to fetch mirror+file:/etc/apt/mirrors/debian.list/dists/trixie/InRelease Could not resolve 'updates.mydomain.local'
W: Failed to fetch mirror+file:/etc/apt/mirrors/debian.list/dists/trixie-updates/InRelease Could not resolve 'updates.mydomain.local'
W: Failed to fetch mirror+file:/etc/apt/mirrors/debian.list/dists/trixie-backports/InRelease Could not resolve 'updates.mydomain.local'
W: Failed to fetch mirror+file:/etc/apt/mirrors/debian-security.list/dists/trixie-security/InRelease Could not resolve 'updates.mydomain.local'
W: Some index files failed to download. They have been ignored, or old ones used instead.
I enabled query logging on the DNS server (unbound) and it did NOT receive any DNS queries
while running cloud-init.
Appreciate your help,
Laurens Blankers