如何将 Packer ssh 配置到 GCP VM 中以构建镜像？

Question

I am building GCP image with packer. I created service account of "Compute Instance Admin v1" and "Service Account User". It can successfully create the VM but cannot ssh into the instance to proceed further for the custom image.

Error message

Build 'googlecompute.custom-image' errored after 2 minutes 20 seconds: Packer experienced an authentication error when trying to connect via SSH. This can happen if your username/password are wrong. You may want to double-check your credentials as part of your debugging process. original error: ssh: handshake failed: ssh: unable to authenticate, attempted methods [none publickey], no supported methods remain

build file source code (packer.pkr.hcl)

locals {
  project_id              = "project-id"  
  source_image_family     = "rocky-linux-8"           
  source_image_project_id = ["rocky-linux-cloud"]     
  ssh_username            = "packer"                  
  machine_type            = "e2-medium"              
  zone                    = "us-central1-a"  
}

source "googlecompute" "custom-image" {

  image_name = "custom-image"  # Name of image to be created
  image_description       = "Custom Image 1"    # Description for image to be created
  project_id              = "${local.project_id}"
  source_image_family     = "${local.source_image_family}"
  source_image_project_id = "${local.source_image_project_id}"
  ssh_username            = "${local.ssh_username}"
  machine_type            = "${local.machine_type}"
  zone                    = "${local.zone}"
}

build {
  sources = ["source.googlecompute.custom-image"]

  #
  # Run arbitrary shell script file
  #
  provisioner "shell" {
    execute_command = "sudo su - root -c \"sh {{ .Path }} \""
    script          = "foo.sh"
  }

}

Answer 1

It appears that you are having trouble connecting via SSH to the Packer-created instance for your GCP image. If the username and password are incorrect or if the necessary permissions are not granted, this error message indicates that the authentication process failed. Check to see if the Compute Instance Admin v1 and Service Account User roles have the necessary access rights to resolve this issue. In addition, the project's firewall rules may need to be set up to allow incoming SSH connections on the port you're using. You can refer to the official GCP documentation for more information regarding the configuration of firewall rules. You can also connect to the instance and continue troubleshooting the issue by using the "gcloud compute ssh" command.

Attaching troubleshooting ssh for reference.

Answer 2

The problem is associated with Qwiklab. I was using the lab environment provided by Qwiklab for testing packer and GCP.

Once I deployed the same thing on regular GCP project. The packer ran successfully. it is suggested there may be some constraints in the lab environment of Qwiklab.