write_etc_network_interfaces: updated header comment

The header now mentions that the file is auto-generated and
should not be tempered with directly.
It now recommends to add custom network configurations via
source/source-directory lines.

diff --git a/src/PVE/INotify.pm b/src/PVE/INotify.pm
index e773cf4d93649b56c5fc93775abf01a151d4ac84..b3f45ae983798397dcdc9e8b72f95163456f9fd3 100644 (file)
--- a/src/PVE/INotify.pm
+++ b/src/PVE/INotify.pm
@@ -1197,7 +1197,19 @@ sub write_etc_network_interfaces {
        }
     }
 
        }
     }
 

-    my $raw = "# network interface settings\n";
+    my $raw = <<'NETWORKDOC';
+# network interface settings; autogenerated
+# Please do NOT modify this file directly, unless you know what
+# you're doing.
+#
+# If you want to manage part of the network configuration manually,
+# please utilize the 'source' or 'source-directory' directives to do
+# so.
+# PVE will preserve these directives, but will NOT its network
+# configuration from sourced files, so do not attempt to move any of
+# the PVE managed interfaces into external files!
+
+NETWORKDOC

 
     my $printed = {};
 
 
     my $printed = {};