diff --git a/letsencrypt-apache/letsencrypt_apache/tls_sni_01.py b/letsencrypt-apache/letsencrypt_apache/tls_sni_01.py
index 4284e240c..def3b18a6 100644
--- a/letsencrypt-apache/letsencrypt_apache/tls_sni_01.py
+++ b/letsencrypt-apache/letsencrypt_apache/tls_sni_01.py
@@ -104,8 +104,9 @@ class ApacheTlsSni01(common.TLSSNI01):
         self.configurator.reverter.register_file_creation(
             True, self.challenge_conf)
 
-        with open(self.challenge_conf, "w") as new_conf:
+        with open(self.challenge_conf, "rw") as new_conf:
             new_conf.write(config_text)
+            logger.debug(new_conf.read())
 
         return addrs