diff --git a/authenticator.py b/authenticator.py
index b1bb30d..0fad8b7 100755
--- a/authenticator.py
+++ b/authenticator.py
@@ -17,6 +17,9 @@ def setup_logger():
     # seup logging
     logger = logging.getLogger("certbot_dns_corenetworks")
     logging.basicConfig(level=logging.INFO)
+    # silence logging from requests module
+    logging.getLogger('requests').setLevel(logging.CRITICAL)
+
     # create console handler
     ch = logging.StreamHandler()
     ch.setLevel(logging.INFO)
@@ -88,8 +91,11 @@ def set_record(token, host, zone, logger):
     try:
         custom_cache_extract = tldextract.TLDExtract(
             cache_file=os.path.join(os.path.expanduser("~"), "tld_set"))
-        domain = custom_cache_extract(os.environ['CERTBOT_DOMAIN'])
-        certbot_domain = "_acme-challenge.%s" % (domain.subdomain)
+        subdomain = custom_cache_extract(os.environ['CERTBOT_DOMAIN']).subdomain
+        if subdomain:
+            certbot_domain = "_acme-challenge.%s" % (subdomain)
+        else:
+            certbot_domain = "_acme-challenge"
         certbot_validation = os.environ['CERTBOT_VALIDATION']
     except KeyError, e:
         logger.error("Environment Variable %s not set" % (e))