strip gallery lineage stuff

Author: timmy-wright

.pipelines/scripts/windows_build_vhd.sh

@@ -120,6 +120,66 @@ export MANAGED_SIG_ID="$(cat packer-output | grep -a "ManagedImageSharedImageGal
 echo "Found OS_DISK_URI: ${OS_DISK_URI}"
 echo "Found MANAGED_SIG_ID: ${MANAGED_SIG_ID}"
 
+# Break gallery lineage if the build was sourced from a shared gallery.
+# Sometimes Azure requires AutomaticOSUpgrade on VMSS created from images with gallery lineage.
+# Re-creating the SIG image version from a managed disk severs that association.
+sig_source_gallery_name=$(jq -r ".WindowsBaseVersions.\"${WINDOWS_SKU}\".sig_source_gallery_name // empty" <vhdbuilder/packer/windows/windows_settings.json)
+if [ -n "${sig_source_gallery_name}" ] && [ -n "${MANAGED_SIG_ID}" ]; then
+  echo "Build sourced from gallery '${sig_source_gallery_name}' — breaking gallery lineage on SIG image version"
+  LINEAGE_DISK_NAME="lineage-break-${SIG_IMAGE_NAME}-$(date +%s)"
+  LOCATION="${AZURE_LOCATION}"
+
+  echo "Creating managed disk from SIG image version..."
+  az disk create \
+    --resource-group "${AZURE_RESOURCE_GROUP_NAME}" \
+    --name "${LINEAGE_DISK_NAME}" \
+    --gallery-image-reference "${MANAGED_SIG_ID}" \
+    --location "${LOCATION}" \
+    --hyper-v-generation "${HYPERV_GENERATION:-V2}" \
+    --os-type Windows \
+    -o none
+
+  DISK_ID="/subscriptions/${SUBSCRIPTION_ID}/resourceGroups/${AZURE_RESOURCE_GROUP_NAME}/providers/Microsoft.Compute/disks/${LINEAGE_DISK_NAME}"
+  echo "Created disk: ${DISK_ID}"
+
+  echo "Deleting original SIG image version..."
+  az sig image-version delete \
+    --resource-group "${AZURE_RESOURCE_GROUP_NAME}" \
+    --gallery-name "${SIG_GALLERY_NAME}" \
+    --gallery-image-definition "${SIG_IMAGE_NAME}" \
+    --gallery-image-version "${SIG_IMAGE_VERSION}"
+
+  echo "Waiting for deletion to propagate..."
+  az sig image-version wait \
+    --resource-group "${AZURE_RESOURCE_GROUP_NAME}" \
+    --gallery-name "${SIG_GALLERY_NAME}" \
+    --gallery-image-definition "${SIG_IMAGE_NAME}" \
+    --gallery-image-version "${SIG_IMAGE_VERSION}" \
+    --deleted 2>/dev/null || sleep 30
+
+  echo "Re-creating SIG image version from managed disk (no gallery lineage)..."
+  az sig image-version create \
+    --resource-group "${AZURE_RESOURCE_GROUP_NAME}" \
+    --gallery-name "${SIG_GALLERY_NAME}" \
+    --gallery-image-definition "${SIG_IMAGE_NAME}" \
+    --gallery-image-version "${SIG_IMAGE_VERSION}" \
+    --os-snapshot "${DISK_ID}" \
+    --location "${LOCATION}" \
+    --replica-count 1 \
+    -o none
+
+  NEW_SIG_ID="/subscriptions/${SUBSCRIPTION_ID}/resourceGroups/${AZURE_RESOURCE_GROUP_NAME}/providers/Microsoft.Compute/galleries/${SIG_GALLERY_NAME}/images/${SIG_IMAGE_NAME}/versions/${SIG_IMAGE_VERSION}"
+  echo "New SIG image version (lineage-free): ${NEW_SIG_ID}"
+  export MANAGED_SIG_ID="${NEW_SIG_ID}"
+
+  echo "Cleaning up temporary disk..."
+  az disk delete --resource-group "${AZURE_RESOURCE_GROUP_NAME}" --name "${LINEAGE_DISK_NAME}" --yes --no-wait
+
+  echo "1P gallery lineage successfully broken"
+else
+  echo "Build was not sourced from a gallery — no lineage breaking needed"
+fi
+
 # if bash is echoing the commands, then ADO processes both the echo of the command to set the variable and the command itself.
 # This causes super odd behavior in ADO.
 set +x