Getting a Packer build run to complete successfully can be challenging. Getting the write combination of template configuration and scripts is always a challenge. If you stuck trying to get here are a few tips.
Turn on Logging
Enable Packer logging by setting a few environment variables. Set PACKER_LOG = 1 and enter a file path for PACKER_LOG_PATH.
Prevent Cleanup on Error
Inform Packer that it should ask you what to do when it encounters an error instead of just immediately cleaning up all the resources it created.
packer build -on-error=ask mytemplate.json
Log into VM
If examining the log file isn’t enough to resolve the issue, you can leverage our ability to prevent cleanup and log into the VM. So, what is the password? Well the password is not dumped into the console output, which is just fine. You need to open the file at the path you specified for PACKER_LOG_PATH. Once you have that open you can search for “adminPassword” and grab the value that immediately follows it.