vsphere-iso: IPv6 ip_wait_address breaks "Waiting for SSH to become available" due to "too many colons in address".

Overview of the Issue

Whilst creating IPv6-only packer images, we ran into the following problems:

Packer was still waiting/polling for an assigned IP address to the VM, although it had already received an IPv6 address.

This was solved by assigning an IPv6 range (e.g. 2001:db8:dead:beef::/64) to the ip_wait_address variable inside the source "vsphere-iso" "[name]" stanza. This was necessary due to the vSphere ISO builder defaulting to IPv4: https://developer.hashicorp.com/packer/integrations/hashicorp/vsphere/latest/components/builder/vsphere-iso#wait-configuration

Packer was still waiting/polling for SSH to become available, even after passing the IP check.

Still unresolved. The SSH wait seems to continue using the detected IP address of the VM, but doesn't work around the implications of the address being an IPv6 address:

2023/11/29 08:44:32 packer-plugin-vsphere_v1.2.2_x5.0_linux_amd64 plugin: 2023/11/29 08:44:32 VM IP seems stable enough: 2001:db8:dead:beef::1
==> vsphere-iso.adis-tester: IP address: 2001:db8:dead:beef::1
2023/11/29 08:44:32 packer-plugin-vsphere_v1.2.2_x5.0_linux_amd64 plugin: 2023/11/29 08:44:32 [INFO] Waiting for SSH, up to timeout: 30m0s
2023/11/29 08:44:32 packer-plugin-vsphere_v1.2.2_x5.0_linux_amd64 plugin: 2023/11/29 08:44:32 [DEBUG] TCP connection to SSH ip/port failed: dial tcp: address 2001:db8:dead:beef::1:22: too many colons in address
==> vsphere-iso.adis-tester: Using SSH communicator to connect: 2001:db8:dead:beef::1
==> vsphere-iso.adis-tester: Waiting for SSH to become available...
2023/11/29 08:44:37 packer-plugin-vsphere_v1.2.2_x5.0_linux_amd64 plugin: 2023/11/29 08:44:37 [DEBUG] TCP connection to SSH ip/port failed: dial tcp: address 2001:db8:dead:beef::1:22: too many colons in address
2023/11/29 08:44:42 packer-plugin-vsphere_v1.2.2_x5.0_linux_amd64 plugin: 2023/11/29 08:44:42 [DEBUG] TCP connection to SSH ip/port failed: dial tcp: address 2001:db8:dead:beef::1:22: too many colons in address

Might be the same problem as described in https://github.com/hashicorp/packer/issues/9360.

Reproduction Steps

Follow the tutorial steps in https://developer.hashicorp.com/terraform/tutorials/virtual-machine/vsphere-provider.
Pivot from the tutorial and assign a static IPv6 address using CloudInit's user-data.
Declare ip_wait_address and assign it an IPv6 range as a string inside packer/vsphere-iso_basic_ubuntu.pkr.hcl.
Run PACKER_LOG=1 packer build. It will wait/poll for SSH to become available indefinitely.

Packer Version

Packer v1.9.4

Plugin Version and Builders

Plugin: packer-plugin-vsphere_v1.2.2_x5.0_linux_amd64

Builder: vsphere-iso

VMware vSphere Version

7.0.3

Guest Operating System

Both tested with Ubuntu 22.04 LTS and Ubuntu 20.04 LTS.

Simplified Packer Buildfile

https://github.com/hashicorp/learn-terraform-vsphere/blob/main/packer/vsphere-iso_basic_ubuntu.pkr.hcl with ip_wait_address added in the source "vsphere-iso" "[name]" stanza.

https://github.com/hashicorp/learn-terraform-vsphere/blob/main/packer/user-data with added netplan data, e.g:

network:
network:
  version: 2
  renderer: networkd
  ethernets:
    foobar:
      match:
        name: 'ens*'
      dhcp4: false
      dhcp6: false
      addresses:
        - 2001:db8:dead:beef::2/64
      nameservers:
        search: [example.com]
        addresses:
          - 2001:db8:dead:beef::3
          - 2001:db8:dead:beef::4
      routes:
        - to: ::/0
          via: 2001:db8:dead:beef::1

Operating System and Environment Details

Packer was run from my Ubuntu 22.04 LTS desktop.

I ran into the same issue and I have a working "fix" (this could be fixed in packer itself, or elsewhere in the code then where I inserted it).

The issue is somewhere I assume in the packer code packer is plugging whatever IP string it gets into a function that attempts to parse the IP according to: https://www.rfc-editor.org/rfc/rfc2732 . The fix is to introduce [] around the IPv6 address at some step in the process.

https://github.com/bandit145/packer-plugin-vsphere/blob/3d97f937cd61cea4a4819d1f66a439ab9664e76d/builder/vsphere/common/step_wait_for_ip.go#L174

In this example I just do a naive check if a ":" is in the string and concatenate the required brackets around it; this results in a successful connection:

==> centos_stream9.vsphere-iso.image: IP address: [2605:90f4:0:53:250:56ff:fea5:571f] ==> centos_stream9.vsphere-iso.image: Using SSH communicator to connect: [2605:90f4:0:53:250:56ff:fea5:571f] 2024/02/01 12:14:04 packer-plugin-vsphere plugin: 2024/02/01 12:14:04 [INFO] Waiting for SSH, up to timeout: 5m0s ==> centos_stream9.vsphere-iso.image: Waiting for SSH to become available... 2024/02/01 12:14:04 packer-plugin-vsphere plugin: 2024/02/01 12:14:04 [INFO] Attempting SSH connection to [2605:90f4:0:53:250:56ff:fea5:571f]:22... 2024/02/01 12:14:04 packer-plugin-vsphere plugin: 2024/02/01 12:14:04 [DEBUG] reconnecting to TCP connection for SSH 2024/02/01 12:14:04 packer-plugin-vsphere plugin: 2024/02/01 12:14:04 [DEBUG] handshaking with SSH 2024/02/01 12:14:05 packer-plugin-vsphere plugin: 2024/02/01 12:14:05 [DEBUG] handshake complete! 2024/02/01 12:14:05 packer-plugin-vsphere plugin: 2024/02/01 12:14:05 [DEBUG] Opening new ssh session 2024/02/01 12:14:05 packer-plugin-vsphere plugin: 2024/02/01 12:14:05 [INFO] agent forwarding enabled ==> centos_stream9.vsphere-iso.image: Connected to SSH!

I believe (but have not tried) that this could also be fixed in this portion: https://github.com/hashicorp/packer-plugin-vsphere/blob/c76697aef7159648fd1ed343f74f0201ea5c29d7/builder/vsphere/driver/vm.go#L718 by adding some manner of check and then properly formatting the address string if an IPv6 address is detected.

If wanted I could make a PR for whichever option is preferred (even if it's "it should be handled in packer").

hashicorp / packer-plugin-vsphere