Merge pull request #1025 from weaveworks/3152-document-resource-delet…

…ion-workaround

docs: Document a fix to "terraform objects stuck on deletion" issue

docs/how_to/resource_deletion.md

@@ -15,6 +15,25 @@ However, if the source object is unavailable or has been deleted, the re-plannin
 As a result, the Terraform Controller cannot locate the resource state, 
 leading to an infinite deletion attempt cycle, commonly known as a looping process.
 
+If the source object was deleted and the deletion of a Terraform resource is
+stuck, clearing the `finalizers` let the system delete the resource skipping
+the finalizer of the Terraform Controller.
+
+1. Suspend the `kustomization`:
+   ```
+   flux suspend kustomization tf-stk
+   ```
+2. Patch the Terraform resource:
+   ```
+   kubectl patch terraforms.infra.contrib.fluxcd.io \
+     -n stk helloworld \
+     -p '{"metadata":{"finalizers":null}}' \
+     --type=merge
+   ```
+
+As it skips the finalizer of the Terraform controller, any cleanup the
+controller would do will be skipped too.
+
 ## Role Bindings
 
 Role bindings assign permissions to Terraform runners, allowing them to execute operations within the Kubernetes cluster.