Fixes a bug where a VM ends up in a state where it does not have a "rendered_templates_archive" in the spec json

src/bosh-director/lib/bosh/director/deployment_plan/instance.rb

@@ -148,6 +148,13 @@ def bind_existing_instance_model(existing_instance_model)
         @model = existing_instance_model
         @desired_variable_set = @deployment_model.last_successful_variable_set || @deployment_model.current_variable_set
         @previous_variable_set = existing_instance_model.variable_set
+        templates_archive = existing_instance_model.latest_rendered_templates_archive
+        if templates_archive
+          self.rendered_templates_archive = Core::Templates::RenderedTemplatesArchive.new(
+            templates_archive.blobstore_id,
+            templates_archive.sha1,
+          )
+        end
       end
 
       def bind_existing_reservations(reservations)

src/bosh-director/lib/bosh/director/rendered_templates_persister.rb

@@ -81,6 +81,10 @@ def send_templates_to_agent(instance_plan)
 
       rendered_templates_archive = instance_plan.rendered_templates.persist_through_agent(instance.agent_client)
 
+      instance.model.add_rendered_templates_archive(rendered_templates_archive.spec.merge({
+        content_sha1: instance.configuration_hash,
+        created_at: Time.now,
+      }))
       instance.rendered_templates_archive = rendered_templates_archive
     end
   end

src/bosh-director/spec/unit/deployment_plan/instance_spec.rb

@@ -96,6 +96,17 @@ module Bosh::Director::DeploymentPlan
           expect(instance.previous_variable_set).to eq(variable_set_model)
         end
       end
+
+      context 'if there is an existing rendered_templates_archive for the model' do
+        let!(:rendered_templates_archive) { FactoryBot.create(:models_rendered_templates_archive, instance: instance_model) }
+
+        it 'configures the instance to have the same rendered_templates_archive as the existing model' do
+          instance.bind_existing_instance_model(instance_model)
+
+          expect(instance.rendered_templates_archive.sha1).to eq(rendered_templates_archive.sha1)
+          expect(instance.rendered_templates_archive.blobstore_id).to eq(rendered_templates_archive.blobstore_id)
+        end
+      end
     end
 
     describe '#bind_new_instance_model' do

src/bosh-director/spec/unit/rendered_templates_persister_spec.rb

@@ -10,7 +10,10 @@ module Bosh::Director
         let(:instance_plan) { instance_double('Bosh::Director::DeploymentPlan::InstancePlan') }
         let(:instance) { instance_double('Bosh::Director::DeploymentPlan::Instance') }
 
-        let(:rendered_templates_archive) { instance_double('Bosh::Director::Core::Templates::RenderedTemplatesArchive') }
+        let(:blobstore_id) { 'generated-blobstore-id' }
+        let(:sha1) { 'generated-sha1' }
+        let(:configuration_hash) { 'configuraiton-hash' }
+        let(:rendered_templates_archive) { Bosh::Director::Core::Templates::RenderedTemplatesArchive.new(blobstore_id, sha1) }
 
         let(:rendered_job_instance) { instance_double('Bosh::Director::Core::Templates::RenderedJobInstance') }
 
@@ -32,6 +35,8 @@ module Bosh::Director
 
           allow(instance).to receive(:rendered_templates_archive=)
           allow(instance).to receive(:agent_client).and_return(agent_client)
+          allow(instance).to receive(:model).and_return(FactoryBot.create(:models_instance))
+          allow(instance).to receive(:configuration_hash).and_return(configuration_hash)
 
           allow(SecureRandom).to receive(:uuid).and_return(blobstore_id)
         end
@@ -55,7 +60,7 @@ module Bosh::Director
 
           it 'should deliver the templates through NATS' do
             allow(Base64).to receive(:encode64).with(template_contents).and_return(mock_base64_contents)
-            expect(rendered_job_instance).to receive(:persist_through_agent).with(agent_client)
+            expect(rendered_job_instance).to receive(:persist_through_agent).with(agent_client).and_return(rendered_templates_archive)
 
             persister.persist(instance_plan)
           end
@@ -67,6 +72,18 @@ module Bosh::Director
             persister.persist(instance_plan)
           end
 
+          it 'persists the rendered_templates_archive for the instance model' do
+            allow(rendered_job_instance).to receive(:persist_through_agent).with(agent_client).and_return(rendered_templates_archive)
+
+            persister.persist(instance_plan)
+
+            rendered_templates_archive = instance.model.latest_rendered_templates_archive
+            expect(rendered_templates_archive).to be
+            expect(rendered_templates_archive.content_sha1).to eq(configuration_hash)
+            expect(rendered_templates_archive.sha1).to eq(sha1)
+            expect(rendered_templates_archive.blobstore_id).to eq(blobstore_id)
+          end
+
           context 'when persist through agent fails with AgentUnsupportedAction error' do
             it 'should delegate to persist_to_blobstore' do
               allow(rendered_job_instance).to receive(:persist_through_agent)