VM is not booting up in Azure dual stack- IMDS server connection timing out in cloud-init script

[mahudees]

Bug report

VM is not booting up as IMDS server connection timing out in cloud-init script.

Steps to reproduce the problem

1. Deploy a Ubuntu VM in Azure via Azure Java SDK with 2 interfaces connected to a dual stack subnet.
2. While booting the VM post deployment, booting got stuck in clout-init, waiting to connect with IMDS service.

Issue happens only when the VM is deployed using Azure SDK in a dual stack environment, with two interfaces in dual stack. Issue is not observed when deployed from Azure portal with Vm having one interface. Issue not seen when the interfaces are in IPv4 only network.

Environment details

• Cloud-init version: Cloud-init v. 23.1.2-0ubuntu0~22.04.1
• Operating System Distribution: Ubuntu 22.04.5 LTS
• Cloud provider, platform or installer type: Azure, VM installed using Azure SDK.

cloud-init logs

Not able to SSH into the machine, attaching the boot log from console.

non_working_azure.txt