#Troubleshooting
#Build stuck in Networking
Network resources couldn't be created. Check that:
- Your CIDRs don't overlap with existing reserved ranges (the egress subnet is typically
172.17.0.0/16). - VPC and subnet names are valid DNS labels (lowercase letters, digits, hyphens).
#Build stuck in Booting, never reaches Provisioning
The VM booted but SSH never came up. Common causes:
- Cloud image without a
cloudInitblock: cloud-init never runs, no SSH key gets injected. - Wrong
sshUsernamefor the distro (ubuntuvs.debianvs.cloud-user). - For ISO installs: the boot command didn't drive the installer correctly. Watch the VNC console through the UI to see what's actually on screen.
- For Windows: Autounattend.xml didn't run. Open VNC during the build to see if Setup is asking interactive questions.
sshTimeoutis shorter than the install actually takes. Bump it up.
#Provisioner fails with permission errors
Linux: many cloud-image users don't have passwordless sudo. The build assumes they do, but distro defaults vary. If sudo prompts for a password:
shell:
executeCommand: "echo '{{password}}' | sudo -S sh -c '{{ .Command }}'"
inline: |
apt-get install -y nginx
Or set up passwordless sudo in your preseed/cloud-init.
Windows: PowerShell execution policy can block scripts. Set it explicitly:
Set-ExecutionPolicy -ExecutionPolicy Unrestricted -Force
#windows-update step times out or loops
- Some updates require a reboot before others become eligible. The provisioner handles this with reboots between cycles, but very large update queues can take many cycles.
- Bump
timeoutto several hours. - If specific updates are failing, use
filtersto exclude them.
#Boot command keystrokes happen too early or too late
Insert <wait> or <waitN> at strategic points. ISO installers are timing-sensitive. When in doubt, watch the build via VNC and time the boot loader yourself.
#Build runs but a cloned VM won't boot
- Is the disk too small for what you installed? Each template VM's disk inherits
disks[].size. - Did you forget to install virtio drivers (Windows)? Without
netkvm/vioscsi, clones fail to boot or fail to network. - Did you change NIC
modelbetween build and clone without installing the matching driver? - Did you cleanly shut down? End each VM's provisioners with a
rebootso the captured disk isn't in a half-flushed state.
#Inspecting a stuck build
- Open the build in the UI to see its current phase, conditions, and any error message.
- Watch recent events / log output for the build.
- Open the affected VM's VNC console through the UI to see what's on screen during a hang.
- Insert a
handbuildprovisioner at the suspect step to pause the build and inspect interactively.