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Comment by buremba | Hacker News Reader

1. We can't test the templates in local environment, the only way to test a template is to create a real cluster which usually takes ~15 minutes.

2. The error messages are not helpful enough. It usually fails with "SETUP_FAILED" error with no proper error cause.

3. The rollback may not work if you change the configuration. You need to delete the resources manually or even need to get help from Amazon since the resources stuck at some failed status.

4. The JSON template is hard to write and read. We have a fat single file template that has 2k lines and scared to change it since we might broke something.

5. Not all AWS actions are supported. For example we need to add custom resources (ELB and RDS instances) to a Opsworks stack but it's not possible with Cloudformation.

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1. This is true, but also valid of other cloud provisioning tools. Some operations just take a long time. Using things like DependsOn and template validation help decrease provisioning time.

2. If you check the events that happened in the CloudFormation console or by running "aws cloudformation describe-stack-events", you'll see where things went sideways pretty easily (unless you're using nested stacks, in which case debugging can take a bit longer.)

3. I can't say that that's happened too often for us, and we've deployed quite a few stacks so far.

4. Your stacks shouldn't be super long. If you're using Designer to create your template (which I personally don't do), removing the position metadata can save you lots of lines depending on the number of resources you have. Also, you might be mixing in parts of your infrastructure that should really live in their own stacks (I.e. Not creating web servers in your VPC/networking stack). Consider using nested stacks to help you organize this.

5. What do you mean? Tagging is supported by most CF resources (and AWS is adding support for more as the product matures)

I'm not a CloudFormation superfan, but...

1. Yup.

2. In my experience, the error message is usually fine, but there are many times where it's completely obtuse.

3. They just added a new feature to help with this. When you get ROLLBACK_FAILED, you can now tweak things and retry the rollback. It has helped me a few times not have to contact support recently.

4. 100% agree. I write all my templates in yaml, which helps a lot. I really hope they just add native yaml support. Example[1]

5. You can now create custom resources using Lambda from within your templates, which is pretty cool. Example[1]

edit: I should add that at my company, we mostly use Terraform now. I still like to use CF for projects that will be open-sourced though, as I don't want step 1 of my instructions to be "install terraform".

[1] https://github.com/zwily/sqs-to-lambda-via-lambda

Can't counter these points other than that what else is there to automate AWS infrastructure? Terraform suffers all these problems, too.

I don't have experience with Terraform but it should be possible to find a way to fix these issues except the first one.

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