[3.0.1-rc6] order of cicustom elements forces replacement of entire vm

[kagehisa]

Im using the cicustom attribute to provide my VMs with a cloud-init config that consists of meta-data, network-config and user-data. In code this looks something like this:

cicustom = "user=cloud-init:snippets/user_data_vm-${lower(each.value.name)}.yml,meta=cloud-init:snippets/meta_data_vm-${lower(each.value.name)}.yml,network=cloud-init:snippets/network_config_vm-${lower(each.value.name)}.yml"

This works and my VM's get successfully deployed. But when make a change to the code i.e. assign more ram or something else that would not justify a replacement, I get the following output from terrafrom apply/plan (example for vm name lff-r-vslnxc04):

~ cicustom  = "meta=cloud-init:snippets/meta_data_vm-lff-r-vslnxc04.yml,network=cloud-init:snippets/network_config_vm-lff-r-vslnxc04.yml,user=cloud-init:snippets/user_data_vm-lff-r-vslnxc04.yml" 
-> "user=cloud-init:snippets/user_data_vm-lff-r-vslnxc04.yml,meta=cloud-init:snippets/meta_data_vm-lff-r-vslnxc04.yml,network=cloud-init:snippets/network_config_vm-lff-r-vslnxc04.yml" # forces replacement

The order of the cloud-init files that is received from the current state is different to the order I have in code. I would assume this should be no problem, but this triggers a complete destroy and reapply of my infrastructure. When I change my code to reflect the cicustom order which the current state provides it works and all the desired vms get an update instead of a replacement.

So the issue is rather minor and could probably be addressed by a comment in the documentation regarding the ordering of the cicustom cloud-init config elements. I don't know if this behavior is intentional hence I decided to report it just in case.

[Tinyblargon]

@kagehisa Thank you for reporting this bug. The logic should be updated to not care about the order of those items.