openstack: avoid unneeded metadata probe on non-openstack platforms

OpenStack datasource is now discovered in init-local stage. In order to
probe whether OpenStack metadata is present, it performs a costly
sandboxed dhclient setup and metadata probe against http://169.254.169.254
for openstack data.

Cloud-init properly detects non-OpenStack on EC2, but it spends precious
time probing the metadata service also resulting in a confusing WARNING
log about 'metadata not present'. To avoid the wasted cycles, and
confusing warning, get_data will call a detect_openstack function to
quickly determine whether the platform looks like OpenStack before trying
to setup network to probe and crawl the metadata service.

LP: #1776701

1 files changed, 23 insertions, 0 deletions

diff --git a/cloudinit/sources/DataSourceOpenStack.py b/cloudinit/sources/DataSourceOpenStack.py
index 1a12a3f1..365af96a 100644
--- a/cloudinit/sources/DataSourceOpenStack.py
+++ b/cloudinit/sources/DataSourceOpenStack.py
@@ -23,6 +23,13 @@ DEFAULT_METADATA = {
     "instance-id": DEFAULT_IID,
 }
 
+# OpenStack DMI constants
+DMI_PRODUCT_NOVA = 'OpenStack Nova'
+DMI_PRODUCT_COMPUTE = 'OpenStack Compute'
+VALID_DMI_PRODUCT_NAMES = [DMI_PRODUCT_NOVA, DMI_PRODUCT_COMPUTE]
+DMI_ASSET_TAG_OPENTELEKOM = 'OpenTelekomCloud'
+VALID_DMI_ASSET_TAGS = [DMI_ASSET_TAG_OPENTELEKOM]
+
 
 class DataSourceOpenStack(openstack.SourceMixin, sources.DataSource):
 
@@ -114,6 +121,8 @@ class DataSourceOpenStack(openstack.SourceMixin, sources.DataSource):
             False when unable to contact metadata service or when metadata
             format is invalid or disabled.
         """
+        if not detect_openstack():
+            return False
         if self.perform_dhcp_setup:  # Setup networking in init-local stage.
             try:
                 with EphemeralDHCPv4(self.fallback_interface):
@@ -205,6 +214,20 @@ def read_metadata_service(base_url, ssl_details=None,
     return reader.read_v2()
 
 
+def detect_openstack():
+    """Return True when a potential OpenStack platform is detected."""
+    if not util.is_x86():
+        return True  # Non-Intel cpus don't properly report dmi product names
+    product_name = util.read_dmi_data('system-product-name')
+    if product_name in VALID_DMI_PRODUCT_NAMES:
+        return True
+    elif util.read_dmi_data('chassis-asset-tag') in VALID_DMI_ASSET_TAGS:
+        return True
+    elif util.get_proc_env(1).get('product_name') == DMI_PRODUCT_NOVA:
+        return True
+    return False
+
+
 # Used to match classes to dependencies
 datasources = [
     (DataSourceOpenStackLocal, (sources.DEP_FILESYSTEM,)),