I'm trying to install the RKE provider as part of the Rancher AWS quickstart. The Terraform documentation says that plugins should be installed at ~/.terraform.d/plugins. The RKE documentation says that the plugin should be installed at ~/terraform.d/plugins/<your_platform>.
Trying to reconcile the conflicting information, I tried copying the binary to all of the following locations, but Terraform never saw any of them:
~/.terraform.d/plugins/terraform-provider-rke
~/.terraform.d/plugins/rke
~/.terraform.d/plugins/darwin_amd64/terraform-provider-rke
~/.terraform.d/plugins/darwin_amd64/rke
~/terraform.d/plugins/terraform-provider-rke
~/terraform.d/plugins/rke
~/terraform.d/plugins/darwin_amd64/terraform-provider-rke
~/terraform.d/plugins/darwin_amd64/rke
In each case, when I ran terraform init, I got the following error:
Provider "rke" not available for installation.
A provider named "rke" could not be found in the Terraform Registry.
This may result from mistyping the provider name, or the given provider may
be a third-party provider that cannot be installed automatically.
In the latter case, the plugin must be installed manually by locating and
downloading a suitable distribution package and placing the plugin's executable
file in the following directory:
terraform.d/plugins/darwin_amd64
Terraform detects necessary plugins by inspecting the configuration and state.
To view the provider versions requested by each module, run
"terraform providers".
Error: no provider exists with the given name
As a last resort, I could use terraform init -plugin-dir=<something>. But then Terraform doesn't see any of the automatically downloaded plugins, and I have to manually install everything.
Is there some path variable that's missing, or some other naming convention that I am failing to follow?
It turns out that the error message didn't tell the whole story. Terraform was finding the provider, but it didn't think it was a new enough version.
According to Terraform's documentation, the provider needs to be named as terraform-provider-<NAME>_vX.Y.Z. The documentation for the RKE provider said that the file should be called terraform-provider-rke (no version number).
In a comment in the Terraform source code for plugin discovery, it says that this versionless format is supported for reverse compatibility. However, Terraform interprets the version to be v0.0.0.
When I ran terraform plan after the failed terraform init, it gave me a more informative error message:
Error: provider.rke: no suitable version installed
version requirements: "0.14.1"
versions installed: "0.0.0"
That version is presumably a requirement from another provider that depends on the RKE provider.
I went back and manually downloaded that exact version from the Github repo and copied it into the plugins directory with the name terraform-provider-rke_v0.14.1. It worked!
So there you go. When in doubt, look at the source code. Now to submit an issue report to Rancher, telling them to update their documentation. :-)