diff --git a/python-eventlet.spec b/python-eventlet.spec
index 4a24b2d..39aaffe 100644
--- a/python-eventlet.spec
+++ b/python-eventlet.spec
@@ -37,6 +37,7 @@ BuildRequires:  python-rpm-macros
 %if %python_version_nodots < 34
 Requires:       python-enum34
 %endif
+# eventlet parses /etc/protocols which is not available in normal build envs
 Requires:       netcfg
 Requires:       python-greenlet >= 0.3
 BuildRoot:      %{_tmppath}/%{name}-%{version}-build