diff --git a/packaging/prefixes.conf b/packaging/prefixes.conf
new file mode 100644
index 0000000..ca472b9
--- /dev/null
+++ b/packaging/prefixes.conf
@@ -0,0 +1,5 @@
+# Output prefixes here, one per line.  Prefix is in:
+# prefix/netmask format
+# Like this:
+# 192.168.0.0/16
+# 192.0.43.10/32