ARM Templates vs Terraform in Azure

Question

ARM Templates vs Terraform in Azure

cloudguy2020 76

Hi,

Please let me know the differences between ARM Templates vs Terraform in Azure?

Thanks

Mahesh Bramandlapally 1 Reputation point

2022-02-28T10:52:02.39+00:00

Hi Sam,
Thank you for the differences.

Could you please let us know on below point

Can lag behind when new Azure resources are released?? - After how many days/weeks it gets updated with Terraform, any idea?

Thanks in advance.

3 answers

Your answer

Mahesh Bramandlapally 1 Reputation point

2022-02-28T10:52:02.39+00:00

Hi Sam,
Thank you for the differences.

Could you please let us know on below point

Can lag behind when new Azure resources are released?? - After how many days/weeks it gets updated with Terraform, any idea?

Thanks in advance.

Answer 1

Sam Cogan 10,812 Microsoft Employee Volunteer Moderator

ARM templates and Terraform are both Infrastructure as Code tools for deploying cloud resources. A very high level summary of the differences is below

ARM Templates

Azure specific
Get the latest Azure resources as they are released
Does not maintain a state file
Written in JSON
Does not have a Destroy/Cleanup command

Terraform

Supports multiple cloud providers and on-prem resources
Can lag behind when new Azure resources are released
Relies on a state file that must be maintained
Written in HCL, a custom DSL from Hashicorp
Able to cleanup/destroy resources

Both tools can be used to create resources in Azure, they both have positives and negatives compared to each other.

Abhishek Maitrey 6 Reputation points

2020-08-08T06:29:38.76+00:00

Hi Sam,

Well explained answer indeed but I would like to add a point

ARM template follows the explicit sequencing as declared in the template whereas Terraform can automatically manages the depency of resources itself as it is imperative.

Answer 2

cloudguy2020 76

Thank you Sam. Can you please confirm all the below belongs to the same category - Infrastructure as Code(IAC)

ARM Templates
Terraform
Chef
Puppet
Ansible
SaltStack
CloudFormation

Sam Cogan 10,812 Reputation points Microsoft Employee Volunteer Moderator

2020-08-07T15:25:39.463+00:00

I would not necessarily group all these together.

ARM Template, Terraform and Cloudformation are all IaC tools for deploying infrastructure.

Chef, Puppet, Ansible and SaltStack are configuration management tools. They generally deal with configuring your infrastructure, mainly VMs, once they are deployed. For the most part you wouldn't use configuration management to create the VM in the first place, but you would use it to configure the OS and applications in the VM.

There are some grey areas, as some config management tools allow you to deploy infrastructure, but generally not very well.
Mike Williamson 1 Reputation point

2021-01-13T12:11:16.317+00:00

@Sam Cogan 's answer is absolutely correct.

I want to add more to maybe simplify or clarify:

If you think of it as a flow diagram:

Start ==> IaC (ARM, Terraform, Cloudformation) ==> Configure (Chef, Puppet, etc) (Optional)

As more tasks move from VMs to Containers, those configuration tools will be less critical. Instead, it would look like:

Start ==> IaC ==> Container Launch (typically pulling an image from a container registry and loading/installing it on a container instance)
Sam Cogan 10,812 Reputation points Microsoft Employee Volunteer Moderator

2023-03-03T12:54:12.0333333+00:00

Deleted

Answer 3

Grmacjon-MSFT 19,151 Moderator

Hi @haris khan ,

Yes, the list of tools you shared is considered Infrastructure as Code(IAC) tools.

-Grace

Share via

ARM Templates vs Terraform in Azure

3 answers

Your answer