Reboot with mac2.metal fails

Packer
1

Good day all.

I’m having some trouble finding the root cause of my problem and I hope somebody here can shed some light on the situation.

My config looks like:

{
    "builders": [
        {
            "type": "amazon-ebs",
            "region": "us-east-1",
            "ami_name": "{{user `build_id`}}",
            "ssh_username": "{{user `vm_username`}}",
            "ssh_timeout": "2h",
            "ssh_read_write_timeout": "2h",
            "ssh_interface": "public_ip",
            "communicator": "ssh",
            "ami_virtualization_type": "hvm",
            "tenancy": "host",
            "ebs_optimized": "true",
            "instance_type": "mac2.metal",
            "vpc_id": "{{ user `vpc_id` }}",
            "subnet_id": "{{ user `subnet_id` }}",
            "associate_public_ip_address": true
            -- SNIP block devices, AMI, tmp IAM --
        }
    ],
    "provisioners": [
        {
            "type": "shell",
            "inline": [
                "PDISK=$(diskutil list physical external | head -n1 | cut -d' ' -f1)",
                "APFSCONT=$(diskutil list physical external | grep Apple_APFS | tr -s ' ' | cut -d' ' -f8)",
                "yes | sudo diskutil repairDisk $PDISK",
                "sudo diskutil apfs resizeContainer $APFSCONT 0"
              ]
        },
        {
            "type": "shell",
            "execute_command": "chmod +x {{ .Path }}; sudo {{ .Vars }} {{ .Path }}",
            "script": "./reboot.sh",
            "skip_clean": true,
            "expect_disconnect": true
        },
       {  
            "type": "shell",
            "start_retry_timeout": "1800s",
            "inline": "<more commands here>"
        }
    ]  
}

Once the reboot script is run, the connection with the server is broken and packer attempts to reconnect. After roughly 5 minutes the packer run fails with:

2022/12/22 12:56:08 [INFO] 38 bytes written for 'uploadData'
2022/12/22 12:56:08 packer-plugin-amazon_v1.1.6_x5.0_linux_amd64 plugin: 2022/12/22 12:56:08 [DEBUG] Opening new ssh session
2022/12/22 12:56:08 packer-plugin-amazon_v1.1.6_x5.0_linux_amd64 plugin: 2022/12/22 12:56:08 [ERROR] ssh session open error: 'client not available', attempting reconnect
2022/12/22 12:56:08 packer-plugin-amazon_v1.1.6_x5.0_linux_amd64 plugin: 2022/12/22 12:56:08 [DEBUG] reconnecting to TCP connection for SSH
2022/12/22 12:56:23 packer-plugin-amazon_v1.1.6_x5.0_linux_amd64 plugin: 2022/12/22 12:56:23 [ERROR] reconnection error: dial tcp 3.88.221.153:22: i/o timeout
2022/12/22 12:56:23 packer-provisioner-shell plugin: Retryable error: Error uploading script: dial tcp 3.88.221.153:22: i/o timeout
2022/12/22 12:56:23 [INFO] (telemetry) ending shell

At which point provisioning stops and the cleanup starts.

As per config has ssh_timeout, ssh_read_write_timeout and start_retry_timeout has values much higher than 5 minutes and I’ve tried pause_before as well, but it fails after 5 minutes.

I cannot figure out where to extend this wait time as the reboot of mac2.metal machines take 15-30 minutes on AWS.

Any help would be most welcome.

Kind regards
Henti