The Challenge of VM migration

Migrating VMs specially along with its data disks, between zones can be a daunting task. It involves creating snapshots, creating disks from the snapshots in the new zone, creating VMs using those disks and ensuring that all configurations are correctly set up in the new zone. This process is not only time-consuming but also prone to errors if done manually.

Introducing the Azure VM Migration Tool

To address this challenge, I’ve created a Python script that automates the entire migration process. The tool takes snapshots of the disks attached to a VM in one Azure zone, create new disks using those snapshots in another zone, and create new VM using those disks in another zone and handling all the necessary steps in between. All you need to do is to provide necessary information in a CSV file and it will take care of all the complex tasks.

Key Features

Snapshot Creation: The tool automatically creates snapshots of the disks attached to a VM, ensuring that a consistent state of the disk is captured for migration.
Disks creation in target zone: It then creates disks in the target zone using the snapshots and abstract away the complexity of this operation.
Create VM and attach data disks: Now new VMs are being created in the new zone and all disks are attached to the new VM.
Logging: Throughout the process, the tool provides detailed logging, making it easy to monitor the migration and troubleshoot any issues that may arise.

How It Works

The script requires minimal setup. Users need to provide a CSV file with following information. A sample CSV has also been shared in the repository.

Names of the source VMs
Source VM Resource Group
Operating system type
New Resource Group where new VMs need to be created
Target zone where VMs need to be created
Size of the new VM.

Apart from the above information, following information also needs to be provided in the script.

Virtual Network Name
Subnet Name
Virtual Network

The tool then performs the following steps:

1. Capture Subnet ID: It starts by capturing the subnet ID that will be used in the VM creation process in the target zone.
2. Create Snapshot: The tool creates snapshots of the disks attached to the VM.
3. Create disks from the snapshot: The snapshots are then used to create disk in the target zone.
4. Create VM and Attach Disks: Finally, the new OS disk is used to create new VM in the target zone and the data disks are attached to the VM.

Getting Started

To use the tool, you’ll need Python 3.6.x and the Azure CLI installed on your machine. Then, simply run the script with `python az_vm_migration_tool.py`, passing the name of a CSV file containing the migration parameters as an argument.

Github repo

panwar28/azure_vm_migration_tool: This tool helps you migrate Azure VMs between zones in a bulk. You provide your inputs in CSV, run the tool and sit back and relax. It will do its job. (github.com)

Conclusion

The Azure VM Migration Tool represents a significant step forward in simplifying the process of migrating VMs within Azure. By automating the migration process, it not only saves time but also reduces the potential for errors, making it an invaluable resource for anyone managing Azure VMs.