Unable to connect to UTM vm, defaults to 127.0.0.1 which the VM has a 192.168.x.x IP

[rwideman]

Overview of the Issue

Unable to connect to UTM vm, defaults to 127.0.0.1 which the VM has a 192.168.x.x IP
I have tried the network settings:
-Shared Network
-Bridged (Advanced), dropdown selection is auto, also tried en0

Plugin and Packer version

Packer version: 1.12.0
packer-plugin-utm_v0.3.3_x5.0_darwin_arm64

Simplified Packer Buildfile

packer {
required_plugins {
utm = {
version = ">=v0.0.2"
source = "github.com/naveenrajm7/utm"
}
}
}
source "utm-utm" "basic-example" {
source_path = "/Users/rwideman/Library/Containers/com.utmapp.UTM/Data/Documents/Debian 12.utm"
#vm_name = "Debian 12"
ssh_username = "vagrant"
ssh_password = "vagrant"
shutdown_command = "echo 'vagrant' | sudo poweroff"
#timeout = "2m"
}
build {
sources = [ "source.utm-utm.basic-example" ]
}

Logs:
(https://gist.github.com/rwideman/cb5df47d9227fc676beffba7225b8f33)

Operating system and Environment details

Macbook Pro M1 Pro
MacOS 15.4.1

Any help would be appreciated.

[naveenrajm7]

Hi @rwideman ,

Packer by default uses 127.0.0.1 as the ssh_host while using ssh communicator.
For utm-utm builder, we use the same. To be specific the builder uses port forward feature of UTM to deterministically connect to the VM using localhost and ssh forwarded port.

So you have two options.

1. (Recommended) Have Emulated VLAN as your second network interface in the VM with dhcp enabled so that the port forwarding works and packer will be able to connect to VM using localhost and port.
2. Try to guess the IP that your VM might get, which is usually +1 of last used IP. Use the guessed IP in the ssh_host of your packer config.

Hope this helps.

[rwideman]

There is no option for emulated vlan, I found this utmapp/UTM#5067

I tried #2 and still packer trying to connect to 127.0.0.1
source "utm-utm" "basic-example" {
ssh_host = "192.168.106.2"
source_path = "/Users/rwideman/Library/Containers/com.utmapp.UTM/Data/Documents/Debian 12.utm"
ssh_username = "vagrant"
ssh_password = "vagrant"
shutdown_command = "echo 'vagrant' | sudo poweroff"
}

[rwideman]

I tried the following:
source "utm-utm" "basic-example" {
communicator = "ssh"
ssh_host = "192.168.106.2"
ssh_port = 22
source_path = "/Users/rwideman/Library/Containers/com.utmapp.UTM/Data/Documents/Debian 12.utm"
ssh_username = "vagrant"
ssh_password = "vagrant"
shutdown_command = "echo 'vagrant' | sudo poweroff"
}

This I was then able to ssh to in another terminal session and connect, ssh vagrant@192.168.106.2, successfully but packer just sits trying to connect:
$ packer build .
utm-utm.basic-example: output will be in this color.

==> utm-utm.basic-example: Retrieving UTM
==> utm-utm.basic-example: Trying /Users/rwideman/Library/Containers/com.utmapp.UTM/Data/Documents/Debian 12.utm
==> utm-utm.basic-example: Using utm file inplace
==> utm-utm.basic-example: Importing VM: /Users/rwideman/Library/Containers/com.utmapp.UTM/Data/Documents/Debian 12.utm
==> utm-utm.basic-example: Creating forwarded port mapping for communicator (SSH, WinRM, etc) (host port 3634)
==> utm-utm.basic-example: Starting the virtual machine...
==> utm-utm.basic-example: Using SSH communicator to connect: 192.168.106.2
==> utm-utm.basic-example: Waiting for SSH to become available...

I also tried before and after kicking off a new packer build but nogo. If I do this before a new packer build then the vm gets 192.168.107.2 IP and the build sits trying to connect.
sudo ifconfig lo0 192.168.106.2 alias

Just weird.

[rwideman]

I am now finding that the port is changing in the logs, its never the same. So forwarding 127.0.0.1 port anything would fail.

2025/04/30 00:05:05 packer-plugin-utm_v0.3.3_x5.0_darwin_arm64 plugin: 2025/04/30 00:11:53 Looking for available communicator (SSH, WinRM, etc) port between 2222 and 4444
2025/04/30 00:05:05 packer-plugin-utm_v0.3.3_x5.0_darwin_arm64 plugin: 2025/04/30 00:05:05 Found available port: 2573 on IP: 127.0.0.1
2025/04/30 00:05:05 ui: �[1;32m==> utm-utm.basic-example: Creating forwarded port mapping for communicator (SSH, WinRM, etc) (host port 2573)�[0m

2025/04/30 00:11:53 packer-plugin-utm_v0.3.3_x5.0_darwin_arm64 plugin: 2025/04/30 00:11:53 Looking for available communicator (SSH, WinRM, etc) port between 2222 and 4444
2025/04/30 00:11:53 packer-plugin-utm_v0.3.3_x5.0_darwin_arm64 plugin: 2025/04/30 00:11:53 Found available port: 3303 on IP: 127.0.0.1
2025/04/30 00:11:53 ui: ==> utm-utm.debian: Creating forwarded port mapping for communicator (SSH, WinRM, etc) (host port 3303)

2025/04/30 00:13:15 packer-plugin-utm_v0.3.3_x5.0_darwin_arm64 plugin: 2025/04/30 00:13:15 Looking for available communicator (SSH, WinRM, etc) port between 2222 and 4444
2025/04/30 00:13:15 packer-plugin-utm_v0.3.3_x5.0_darwin_arm64 plugin: 2025/04/30 00:13:15 Found available port: 4336 on IP: 127.0.0.1
2025/04/30 00:13:15 ui: ==> utm-utm.debian: Creating forwarded port mapping for communicator (SSH, WinRM, etc) (host port 4336

[naveenrajm7]

Okay. So this plugin has only been tested for QEMU backed VMs.
Apple backed VMs are not supported.

Re: IP address, As said earlier shared network interface dynamic gets IP, that is the reason this plugin relies on Emulated VLAN to deterministically connect to VM.

Due to the limitation of Apple backed VMs not allowing Emulated interfaces and Shared network interfaces (vmnet) not allowing static IPs, it is difficult to support Apple backed VMs.

Share what you are trying to do, and how would you automate. ie no manual inspection of VM IP.
We can add those ideas into to utm-utm builder if it helps others to bake Apple backed VMs using this plugin.